Revert removal of intrinsics

Oops. We can't do this yet until the next snapshot.

25 files changed, 1038 insertions, 32 deletions

diff --git a/Makefile.in b/Makefile.in
index 71aca347d68..075e15320d5 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -317,6 +317,7 @@ HSREQ$(1)_H_$(3) = \
 TSREQ$(1)_T_$(2)_H_$(3) = \
 	$$(HSREQ$(1)_H_$(3)) \
 	$$(TLIB$(1)_T_$(2)_H_$(3))/$$(CFG_RUNTIME) \
+	$$(TLIB$(1)_T_$(2)_H_$(3))/intrinsics.bc \
 	$$(TLIB$(1)_T_$(2)_H_$(3))/libmorestack.a
 
 # Prerequisites for complete stageN targets
diff --git a/mk/clean.mk b/mk/clean.mk
index 1971af04481..80337c1d6e3 100644
--- a/mk/clean.mk
+++ b/mk/clean.mk
@@ -99,6 +99,8 @@ clean$(1)_T_$(2)_H_$(3):
 	$(Q)rm -f $$(TLIB$(1)_T_$(2)_H_$(3))/$(LIBRUSTC_GLOB)
 	$(Q)rm -f $$(TLIB$(1)_T_$(2)_H_$(3))/$(CFG_RUSTLLVM)
 	$(Q)rm -f $$(TLIB$(1)_T_$(2)_H_$(3))/libstd.rlib
+	$(Q)rm -f $$(TLIB$(1)_T_$(2)_H_$(3))/intrinsics.bc
+	$(Q)rm -f $$(TLIB$(1)_T_$(2)_H_$(3))/intrinsics.ll
 	$(Q)rm -f $$(TLIB$(1)_T_$(2)_H_$(3))/libmorestack.a
 endef
 
diff --git a/mk/install.mk b/mk/install.mk
index 605639c8be1..acd454d1ff4 100644
--- a/mk/install.mk
+++ b/mk/install.mk
@@ -42,6 +42,7 @@ install-target-$(1)-host-$(2): $$(SREQ$$(ISTAGE)_T_$(1)_H_$(2))
 		$$(TL$(1)$(2)),$$(PTL$(1)$(2)),$$(STDLIB_GLOB))
 	$$(Q)$$(call INSTALL_LIB, \
 		$$(TL$(1)$(2)),$$(PTL$(1)$(2)),$$(LIBRUSTC_GLOB))
+	$$(Q)$$(call INSTALL,$$(TL$(1)$(2)),$$(PTL$(1)$(2)),intrinsics.bc)
 	$$(Q)$$(call INSTALL,$$(TL$(1)$(2)),$$(PTL$(1)$(2)),libmorestack.a)
 
 endef
diff --git a/mk/target.mk b/mk/target.mk
index 0f02c153cac..7b3dcab0abd 100644
--- a/mk/target.mk
+++ b/mk/target.mk
@@ -13,6 +13,17 @@ USE_SNAPSHOT_CORELIB=0
 
 define TARGET_STAGE_N
 
+$$(TLIB$(1)_T_$(2)_H_$(3))/intrinsics.ll: \
+		$$(S)src/rt/intrinsics/intrinsics.$(HOST_$(2)).ll.in
+	@$$(call E, sed: $$@)
+	$$(Q)sed s/@CFG_TARGET_TRIPLE@/$(2)/ $$< > $$@
+
+$$(TLIB$(1)_T_$(2)_H_$(3))/intrinsics.bc: \
+		$$(TLIB$(1)_T_$(2)_H_$(3))/intrinsics.ll \
+		$$(LLVM_CONFIG_$(2))
+	@$$(call E, llvms-as: $$@)
+	$$(Q)$$(LLVM_AS_$(2)) -o $$@ $$<
+
 $$(TLIB$(1)_T_$(2)_H_$(3))/libmorestack.a: \
 		rt/$(2)/arch/$$(HOST_$(2))/libmorestack.a
 	@$$(call E, cp: $$@)
diff --git a/src/etc/gen-intrinsics b/src/etc/gen-intrinsics
new file mode 100755
index 00000000000..72785bfbbf6
--- /dev/null
+++ b/src/etc/gen-intrinsics
@@ -0,0 +1,27 @@
+#!/bin/sh
+
+# This script generates new definitions for the intrinsics using
+# clang. This is not currently in the Makefile to avoid any dependency
+# on clang.
+
+for ARCH in i386 x86_64
+do
+    if [ $ARCH = "i386" ]
+    then
+	BITS=32
+    else
+	BITS=64
+    fi
+
+    clang++ -emit-llvm -S -m$BITS -O3 -Isrc/rt/isaac -Isrc/rt/uthash \
+        -Isrc/rt/arch/$ARCH -Isrc/rt -fno-stack-protector \
+        -o src/rt/intrinsics/intrinsics.$ARCH.ll.in \
+        src/rt/intrinsics/intrinsics.cpp
+    sed -i .orig \
+        -e 's/^target datalayout =/; target datalayout =/' \
+        src/rt/intrinsics/intrinsics.$ARCH.ll.in
+    sed -i .orig \
+        -e 's/^target triple = "[^"]*"/target triple = "@CFG_TARGET_TRIPLE@"/' \
+        src/rt/intrinsics/intrinsics.$ARCH.ll.in
+    rm src/rt/intrinsics/intrinsics.$ARCH.ll.in.orig
+done
diff --git a/src/rt/intrinsics/intrinsics.cpp b/src/rt/intrinsics/intrinsics.cpp
new file mode 100644
index 00000000000..d36bdf87675
--- /dev/null
+++ b/src/rt/intrinsics/intrinsics.cpp
@@ -0,0 +1,174 @@
+// Rust intrinsics. These are built into each compilation unit and are
+// run on the Rust stack. They should not call C methods because that
+// will very likely result in running off the end of the stack.
+// Build with the script in src/etc/gen-intrinsics
+
+#include "../rust_internal.h"
+#include "../rust_util.h"
+#include <cstdlib>
+#include <cstring>
+
+extern "C" CDECL void
+rust_task_yield(rust_task *task, bool *killed);
+
+extern "C" void
+rust_intrinsic_vec_len(size_t *retptr,
+                         void *env,
+                         type_desc *ty,
+                         rust_vec **vp)
+{
+    *retptr = (*vp)->fill / ty->size;
+}
+
+extern "C" void
+rust_intrinsic_ptr_offset(void **retptr,
+                          void *env,
+                          type_desc *ty,
+                          void *ptr,
+                          uintptr_t count)
+{
+    *retptr = &((uint8_t *)ptr)[ty->size * count];
+}
+
+extern "C" void
+rust_intrinsic_cast(void *retptr,
+                    void *env,
+                    type_desc *t1,
+                    type_desc *t2,
+                    void *src)
+{
+    // assert t1->size == t2->size
+    // FIXME: This should be easily expressible in rust
+    memmove(retptr, src, t1->size);
+}
+
+extern "C" void
+rust_intrinsic_addr_of(void **retptr,
+                       void *env,
+                       type_desc *ty,
+                       void *valptr) {
+    *retptr = valptr;
+}
+
+struct rust_fn {
+    uintptr_t *fn;
+    rust_box *env;
+};
+
+typedef void (*retptr_fn)(void **retptr,
+			   void *env,
+			   void **dptr);
+// FIXME (1185): This exists just to get access to the return pointer
+extern "C" void
+rust_intrinsic_call_with_retptr(void **retptr,
+				void *env,
+				type_desc *ty,
+				rust_fn *recvfn) {
+    retptr_fn fn = ((retptr_fn)(recvfn->fn));
+    ((retptr_fn)(*fn))(NULL, recvfn->env, retptr);
+}
+
+extern "C" void
+rust_intrinsic_get_type_desc(void **retptr,
+                             void *env,
+                             type_desc* ty) {
+    *(type_desc**)retptr = ty;
+}
+
+extern "C" void
+rust_intrinsic_task_yield(void **retptr,
+                          void *env,
+			  rust_task *task,
+			  bool *killed) {
+    rust_task_yield(task, killed);
+}
+
+extern "C" void
+rust_intrinsic_memmove(void *retptr,
+                    void *env,
+                    type_desc *ty,
+                    void *dst,
+                    void *src,
+                    uintptr_t count)
+{
+    memmove(dst, src, ty->size * count);
+}
+
+extern "C" void
+rust_intrinsic_memcpy(void *retptr,
+                    void *env,
+                    type_desc *ty,
+                    void *dst,
+                    void *src,
+                    uintptr_t count)
+{
+    memcpy(dst, src, ty->size * count);
+}
+
+extern "C" void
+rust_intrinsic_leak(void *retptr,
+                    void *env,
+                    type_desc *ty,
+                    void *thing)
+{
+}
+
+extern "C" CDECL void *
+upcall_shared_realloc(void *ptr, size_t size);
+
+inline void reserve_vec_fast(rust_vec **vpp, size_t size) {
+    if (size > (*vpp)->alloc) {
+      size_t new_size = next_power_of_two(size);
+        size_t alloc_size = new_size + sizeof(rust_vec);
+        // Because this is called from an intrinsic we need to use
+        // the exported API
+        *vpp = (rust_vec*)upcall_shared_realloc(*vpp, alloc_size);
+        (*vpp)->alloc = new_size;
+    }
+}
+
+// Copy elements from one vector to another,
+// dealing with reference counts
+static inline void
+copy_elements(type_desc *elem_t,
+              void *pdst, void *psrc, size_t n) {
+    char *dst = (char *)pdst, *src = (char *)psrc;
+    memmove(dst, src, n);
+
+    // increment the refcount of each element of the vector
+    if (elem_t->take_glue) {
+        glue_fn *take_glue = elem_t->take_glue;
+        size_t elem_size = elem_t->size;
+        const type_desc **tydescs = elem_t->first_param;
+        for (char *p = dst; p < dst+n; p += elem_size) {
+            take_glue(NULL, NULL, tydescs, p);
+        }
+    }
+}
+
+// Because this is used so often, and it calls take glue that must run
+// on the rust stack, it is statically compiled into every crate.
+extern "C" CDECL void
+upcall_intrinsic_vec_push(rust_vec** vp,
+			  type_desc* elt_ty, void* elt) {
+
+    size_t new_sz = (*vp)->fill + elt_ty->size;
+    reserve_vec_fast(vp, new_sz);
+    rust_vec* v = *vp;
+    copy_elements(elt_ty, &v->data[0] + v->fill,
+                  elt, elt_ty->size);
+    v->fill += elt_ty->size;
+}
+
+// FIXME: Transational. Remove
+extern "C" CDECL void
+upcall_vec_push(rust_vec** vp,
+		type_desc* elt_ty, void* elt) {
+  upcall_intrinsic_vec_push(vp, elt_ty, elt);
+}
+
+extern "C" CDECL void
+rust_intrinsic_frame_address(void **p, unsigned n) {
+    *p = __builtin_frame_address(n);
+}
+
diff --git a/src/rt/intrinsics/intrinsics.i386.ll.in b/src/rt/intrinsics/intrinsics.i386.ll.in
new file mode 100644
index 00000000000..a03bed03118
--- /dev/null
+++ b/src/rt/intrinsics/intrinsics.i386.ll.in
@@ -0,0 +1,236 @@
+; ModuleID = 'src/rt/intrinsics/intrinsics.cpp'
+; target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128-n8:16:32"
+target triple = "@CFG_TARGET_TRIPLE@"
+
+%0 = type { i32, %struct.rust_task**, i32 }
+%1 = type { %"struct.hash_map<long, rust_task *>::map_entry"* }
+%class.array_list = type { i32, %"struct.memory_region::alloc_header"**, i32 }
+%class.boxed_region = type { %class.memory_region*, %struct.rust_opaque_box* }
+%class.circular_buffer = type { %class.rust_kernel*, i32, i32, i32, i32, i8* }
+%class.context = type { %struct.registers_t, %class.context*, [12 x i8] }
+%"class.debug::task_debug_info" = type { %"class.std::map" }
+%class.hash_map = type { %"struct.hash_map<long, rust_port *>::map_entry"* }
+%class.indexed_list = type { i32 (...)**, %0 }
+%class.lock_and_signal = type { i32 (...)**, %struct._opaque_pthread_cond_t, %struct._opaque_pthread_mutex_t, %struct._opaque_pthread_t* }
+%class.memory_region = type { i32 (...)**, %class.rust_srv*, %class.memory_region*, i32, %class.array_list, i8, i8, %class.lock_and_signal }
+%class.rust_crate_cache = type { %struct.type_desc*, %struct.rust_hashable_dict*, %struct.rust_task_thread*, i32 }
+%class.rust_kernel = type { %class.memory_region, %class.rust_log, %class.rust_srv*, %class.lock_and_signal, i32, i32, %1, %class.lock_and_signal, i32, %class.lock_and_signal, i32, %"class.std::map", %"class.std::vector", %struct.rust_env* }
+%class.rust_log = type { i32 (...)**, %class.rust_srv*, %struct.rust_task_thread*, i8 }
+%class.rust_obstack = type { %struct.rust_obstack_chunk*, %struct.rust_task* }
+%class.rust_port = type { i32, i32, %class.rust_kernel*, %struct.rust_task*, i32, %class.circular_buffer, %class.lock_and_signal }
+%class.rust_port_selector = type { %class.rust_port**, i32, %class.lock_and_signal }
+%class.rust_scheduler = type opaque
+%class.rust_srv = type { i32 (...)**, %struct.rust_env*, %class.memory_region }
+%class.rust_task_list = type { %class.indexed_list, %struct.rust_task_thread*, i8* }
+%class.rust_thread = type { i32 (...)**, %struct._opaque_pthread_t*, i32 }
+%"class.std::_Rb_tree" = type { %"struct.std::_Rb_tree<long, std::pair<const long, rust_scheduler *>, std::_Select1st<std::pair<const long, rust_scheduler *> >, std::less<long>, std::allocator<std::pair<const long, rust_scheduler *> > >::_Rb_tree_impl" }
+%"class.std::map" = type { %"class.std::_Rb_tree" }
+%"class.std::vector" = type { %"struct.std::_Vector_base" }
+%struct.UT_hash_bucket = type { %struct.UT_hash_handle*, i32, i32 }
+%struct.UT_hash_handle = type { %struct.UT_hash_table*, i8*, i8*, %struct.UT_hash_handle*, %struct.UT_hash_handle*, i8*, i32, i32 }
+%struct.UT_hash_table = type { %struct.UT_hash_bucket*, i32, i32, i32, %struct.UT_hash_handle*, i32, i32, i32, i32, i32 }
+%struct.__darwin_pthread_handler_rec = type { void (i8*)*, i8*, %struct.__darwin_pthread_handler_rec* }
+%struct._opaque_pthread_attr_t = type { i32, [36 x i8] }
+%struct._opaque_pthread_cond_t = type { i32, [24 x i8] }
+%struct._opaque_pthread_mutex_t = type { i32, [40 x i8] }
+%struct._opaque_pthread_t = type { i32, %struct.__darwin_pthread_handler_rec*, [596 x i8] }
+%struct.chan_handle = type { i32, i32 }
+%"struct.hash_map<long, rust_port *>::map_entry" = type opaque
+%"struct.hash_map<long, rust_task *>::map_entry" = type opaque
+%"struct.memory_region::alloc_header" = type { i8 }
+%struct.randctx = type { i32, [256 x i32], [256 x i32], i32, i32, i32 }
+%struct.registers_t = type { i32, i32, i32, i32, i32, i32, i32, i32, i16, i16, i16, i16, i16, i16, i32, i32, [12 x i8] }
+%struct.rust_box = type opaque
+%struct.rust_env = type { i32, i32, i32, i8*, i8, i8, i8* }
+%struct.rust_fn = type { i32*, %struct.rust_box* }
+%struct.rust_hashable_dict = type { %struct.UT_hash_handle, [0 x i8*] }
+%struct.rust_obstack_chunk = type { %struct.rust_obstack_chunk*, i32, i32, i32, [0 x i8] }
+%struct.rust_opaque_box = type { i32, %struct.type_desc*, %struct.rust_opaque_box*, %struct.rust_opaque_box* }
+%struct.rust_shape_tables = type { i8*, i8* }
+%struct.rust_task = type { i32, i32, i8, %struct.chan_handle, [12 x i8], %class.context, %struct.stk_seg*, i32, %class.rust_scheduler*, %struct.rust_task_thread*, %class.rust_crate_cache*, %class.rust_kernel*, i8*, %class.rust_task_list*, %"struct.memory_region::alloc_header"*, i8*, %struct.rust_task*, i32, i32, i32*, %class.memory_region, %class.boxed_region, i8, i8, %class.lock_and_signal, %class.hash_map, %class.rust_obstack, i32, %"class.debug::task_debug_info", i32, i8, i8, %struct.stk_seg*, i32, i32, %class.rust_port_selector, [8 x i8] }
+%struct.rust_task_thread = type { %class.rust_thread, i32, %class.rust_log, i32, %class.rust_srv*, i8*, %class.rust_task_list, %class.rust_task_list, %class.rust_task_list, %class.rust_task_list, %class.rust_crate_cache, %struct.randctx, %class.rust_kernel*, %class.rust_scheduler*, i32, i32, %class.lock_and_signal, i32, %struct._opaque_pthread_attr_t, %struct.rust_env*, [4 x i8], %class.context, i8, %struct.stk_seg*, %struct.stk_seg*, [4 x i8] }
+%struct.rust_vec = type { i32, i32, [0 x i8] }
+%"struct.std::_Rb_tree<long, std::pair<const long, rust_scheduler *>, std::_Select1st<std::pair<const long, rust_scheduler *> >, std::less<long>, std::allocator<std::pair<const long, rust_scheduler *> > >::_Rb_tree_impl" = type { %"struct.memory_region::alloc_header", %"struct.std::_Rb_tree_node_base", i32 }
+%"struct.std::_Rb_tree_node_base" = type { i32, %"struct.std::_Rb_tree_node_base"*, %"struct.std::_Rb_tree_node_base"*, %"struct.std::_Rb_tree_node_base"* }
+%"struct.std::_Vector_base" = type { %"struct.std::_Vector_base<long, std::allocator<long> >::_Vector_impl" }
+%"struct.std::_Vector_base<long, std::allocator<long> >::_Vector_impl" = type { i32*, i32*, i32* }
+%struct.stk_seg = type { %struct.stk_seg*, %struct.stk_seg*, i32, i32, i32, i32, [0 x i8] }
+%struct.type_desc = type { %struct.type_desc**, i32, i32, void (i8*, i8*, %struct.type_desc**, i8*)*, void (i8*, i8*, %struct.type_desc**, i8*)*, void (i8*, i8*, %struct.type_desc**, i8*)*, i8*, void (i8*, i8*, %struct.type_desc**, i8*)*, void (i8*, i8*, %struct.type_desc**, i8*)*, i32, i8*, i8*, %struct.rust_shape_tables*, i32, i32, %struct.UT_hash_handle, i32, [0 x %struct.type_desc*] }
+
+define void @rust_intrinsic_vec_len(i32* nocapture %retptr, i8* nocapture %env, %struct.type_desc* nocapture %ty, %struct.rust_vec** nocapture %vp) nounwind {
+  %1 = load %struct.rust_vec** %vp, align 4
+  %2 = getelementptr inbounds %struct.rust_vec* %1, i32 0, i32 0
+  %3 = load i32* %2, align 4
+  %4 = getelementptr inbounds %struct.type_desc* %ty, i32 0, i32 1
+  %5 = load i32* %4, align 4
+  %6 = udiv i32 %3, %5
+  store i32 %6, i32* %retptr, align 4
+  ret void
+}
+
+define void @rust_intrinsic_ptr_offset(i8** nocapture %retptr, i8* nocapture %env, %struct.type_desc* nocapture %ty, i8* %ptr, i32 %count) nounwind {
+  %1 = getelementptr inbounds %struct.type_desc* %ty, i32 0, i32 1
+  %2 = load i32* %1, align 4
+  %3 = mul i32 %2, %count
+  %4 = getelementptr inbounds i8* %ptr, i32 %3
+  store i8* %4, i8** %retptr, align 4
+  ret void
+}
+
+define void @rust_intrinsic_cast(i8* nocapture %retptr, i8* nocapture %env, %struct.type_desc* nocapture %t1, %struct.type_desc* nocapture %t2, i8* nocapture %src) nounwind {
+  %1 = getelementptr inbounds %struct.type_desc* %t1, i32 0, i32 1
+  %2 = load i32* %1, align 4
+  tail call void @llvm.memmove.p0i8.p0i8.i32(i8* %retptr, i8* %src, i32 %2, i32 1, i1 false)
+  ret void
+}
+
+declare void @llvm.memmove.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i32, i1) nounwind
+
+define void @rust_intrinsic_addr_of(i8** nocapture %retptr, i8* nocapture %env, %struct.type_desc* nocapture %ty, i8* %valptr) nounwind {
+  store i8* %valptr, i8** %retptr, align 4
+  ret void
+}
+
+define void @rust_intrinsic_call_with_retptr(i8** %retptr, i8* nocapture %env, %struct.type_desc* nocapture %ty, %struct.rust_fn* nocapture %recvfn) {
+  %1 = getelementptr inbounds %struct.rust_fn* %recvfn, i32 0, i32 0
+  %2 = load i32** %1, align 4
+  %3 = bitcast i32* %2 to void (i8**, i8*, i8**)*
+  %4 = getelementptr inbounds %struct.rust_fn* %recvfn, i32 0, i32 1
+  %5 = load %struct.rust_box** %4, align 4
+  %6 = bitcast %struct.rust_box* %5 to i8*
+  tail call void %3(i8** null, i8* %6, i8** %retptr)
+  ret void
+}
+
+define void @rust_intrinsic_get_type_desc(i8** nocapture %retptr, i8* nocapture %env, %struct.type_desc* %ty) nounwind {
+  %ty.c = bitcast %struct.type_desc* %ty to i8*
+  store i8* %ty.c, i8** %retptr, align 4
+  ret void
+}
+
+define void @rust_intrinsic_task_yield(i8** nocapture %retptr, i8* nocapture %env, %struct.rust_task* %task, i8* %killed) {
+  tail call void @rust_task_yield(%struct.rust_task* %task, i8* %killed)
+  ret void
+}
+
+declare void @rust_task_yield(%struct.rust_task*, i8*)
+
+define void @rust_intrinsic_memmove(i8* nocapture %retptr, i8* nocapture %env, %struct.type_desc* nocapture %ty, i8* nocapture %dst, i8* nocapture %src, i32 %count) nounwind {
+  %1 = getelementptr inbounds %struct.type_desc* %ty, i32 0, i32 1
+  %2 = load i32* %1, align 4
+  %3 = mul i32 %2, %count
+  tail call void @llvm.memmove.p0i8.p0i8.i32(i8* %dst, i8* %src, i32 %3, i32 1, i1 false)
+  ret void
+}
+
+define void @rust_intrinsic_memcpy(i8* nocapture %retptr, i8* nocapture %env, %struct.type_desc* nocapture %ty, i8* nocapture %dst, i8* nocapture %src, i32 %count) nounwind {
+  %1 = getelementptr inbounds %struct.type_desc* %ty, i32 0, i32 1
+  %2 = load i32* %1, align 4
+  %3 = mul i32 %2, %count
+  tail call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dst, i8* %src, i32 %3, i32 1, i1 false)
+  ret void
+}
+
+declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i32, i1) nounwind
+
+define void @rust_intrinsic_leak(i8* nocapture %retptr, i8* nocapture %env, %struct.type_desc* nocapture %ty, i8* nocapture %thing) nounwind readnone {
+  ret void
+}
+
+define void @upcall_intrinsic_vec_push(%struct.rust_vec** nocapture %vp, %struct.type_desc* nocapture %elt_ty, i8* nocapture %elt) {
+; <label>:0
+  %1 = load %struct.rust_vec** %vp, align 4
+  %2 = getelementptr inbounds %struct.rust_vec* %1, i32 0, i32 0
+  %3 = load i32* %2, align 4
+  %4 = getelementptr inbounds %struct.type_desc* %elt_ty, i32 0, i32 1
+  %5 = load i32* %4, align 4
+  %6 = add i32 %5, %3
+  %7 = getelementptr inbounds %struct.rust_vec* %1, i32 0, i32 1
+  %8 = load i32* %7, align 4
+  %9 = icmp ult i32 %8, %6
+  br i1 %9, label %10, label %_Z16reserve_vec_fastPP8rust_vecm.exit
+
+; <label>:10                                      ; preds = %0
+  %11 = add i32 %6, -1
+  %12 = lshr i32 %11, 1
+  %13 = or i32 %12, %11
+  %14 = lshr i32 %13, 2
+  %15 = or i32 %14, %13
+  %16 = lshr i32 %15, 4
+  %17 = or i32 %16, %15
+  %18 = lshr i32 %17, 8
+  %19 = or i32 %18, %17
+  %20 = lshr i32 %19, 16
+  %21 = or i32 %20, %19
+  %22 = add i32 %21, 1
+  %23 = add i32 %21, 9
+  %24 = bitcast %struct.rust_vec* %1 to i8*
+  %25 = tail call i8* @upcall_shared_realloc(i8* %24, i32 %23)
+  %26 = bitcast i8* %25 to %struct.rust_vec*
+  store %struct.rust_vec* %26, %struct.rust_vec** %vp, align 4
+  %27 = getelementptr inbounds i8* %25, i32 4
+  %28 = bitcast i8* %27 to i32*
+  store i32 %22, i32* %28, align 4
+  %.pr = load i32* %4, align 4
+  %.pre = load %struct.rust_vec** %vp, align 4
+  %.phi.trans.insert = getelementptr inbounds %struct.rust_vec* %.pre, i32 0, i32 0
+  %.pre4 = load i32* %.phi.trans.insert, align 4
+  br label %_Z16reserve_vec_fastPP8rust_vecm.exit
+
+_Z16reserve_vec_fastPP8rust_vecm.exit:            ; preds = %0, %10
+  %29 = phi i32 [ %3, %0 ], [ %.pre4, %10 ]
+  %30 = phi %struct.rust_vec* [ %1, %0 ], [ %.pre, %10 ]
+  %31 = phi i32 [ %5, %0 ], [ %.pr, %10 ]
+  %32 = getelementptr inbounds %struct.rust_vec* %30, i32 0, i32 0
+  %33 = getelementptr inbounds %struct.rust_vec* %30, i32 0, i32 2, i32 %29
+  tail call void @llvm.memmove.p0i8.p0i8.i32(i8* %33, i8* %elt, i32 %31, i32 1, i1 false)
+  %34 = getelementptr inbounds %struct.type_desc* %elt_ty, i32 0, i32 3
+  %35 = load void (i8*, i8*, %struct.type_desc**, i8*)** %34, align 4
+  %36 = icmp eq void (i8*, i8*, %struct.type_desc**, i8*)* %35, null
+  br i1 %36, label %_ZL13copy_elementsP9type_descPvS1_m.exit, label %37
+
+; <label>:37                                      ; preds = %_Z16reserve_vec_fastPP8rust_vecm.exit
+  %38 = load i32* %4, align 4
+  %39 = getelementptr inbounds %struct.type_desc* %elt_ty, i32 0, i32 0
+  %40 = load %struct.type_desc*** %39, align 4
+  %41 = icmp sgt i32 %31, 0
+  br i1 %41, label %.lr.ph.i.preheader, label %_ZL13copy_elementsP9type_descPvS1_m.exit
+
+.lr.ph.i.preheader:                               ; preds = %37
+  %scevgep = getelementptr %struct.rust_vec* %30, i32 1, i32 0
+  %scevgep2 = bitcast i32* %scevgep to i8*
+  br label %.lr.ph.i
+
+.lr.ph.i:                                         ; preds = %.lr.ph.i.preheader, %.lr.ph.i
+  %indvar.i = phi i32 [ %indvar.next.i, %.lr.ph.i ], [ 0, %.lr.ph.i.preheader ]
+  %tmp = mul i32 %38, %indvar.i
+  %tmp2.i = add i32 %38, %tmp
+  %tmp3 = add i32 %29, %tmp
+  %p.01.i = getelementptr i8* %scevgep2, i32 %tmp3
+  tail call void %35(i8* null, i8* null, %struct.type_desc** %40, i8* %p.01.i)
+  %42 = icmp slt i32 %tmp2.i, %31
+  %indvar.next.i = add i32 %indvar.i, 1
+  br i1 %42, label %.lr.ph.i, label %_ZL13copy_elementsP9type_descPvS1_m.exit
+
+_ZL13copy_elementsP9type_descPvS1_m.exit:         ; preds = %.lr.ph.i, %_Z16reserve_vec_fastPP8rust_vecm.exit, %37
+  %43 = load i32* %4, align 4
+  %44 = load i32* %32, align 4
+  %45 = add i32 %44, %43
+  store i32 %45, i32* %32, align 4
+  ret void
+}
+
+define void @upcall_vec_push(%struct.rust_vec** nocapture %vp, %struct.type_desc* nocapture %elt_ty, i8* nocapture %elt) {
+  tail call void @upcall_intrinsic_vec_push(%struct.rust_vec** %vp, %struct.type_desc* %elt_ty, i8* %elt)
+  ret void
+}
+
+define void @rust_intrinsic_frame_address(i8** nocapture %p) nounwind {
+  %1 = tail call i8* @llvm.frameaddress(i32 1)
+  store i8* %1, i8** %p, align 4
+  ret void
+}
+
+declare i8* @llvm.frameaddress(i32) nounwind readnone
+
+declare i8* @upcall_shared_realloc(i8*, i32)
diff --git a/src/rt/intrinsics/intrinsics.ll.bak b/src/rt/intrinsics/intrinsics.ll.bak
new file mode 100644
index 00000000000..8f02e4b3d98
--- /dev/null
+++ b/src/rt/intrinsics/intrinsics.ll.bak
@@ -0,0 +1,149 @@
+; ModuleID = 'intrinsics.cpp'
+target triple = "@CFG_LLVM_TRIPLE@"
+
+%struct.rust_task = type { i32, %struct.stk_seg*, i32, i32, %struct.gc_alloc*, %struct.rust_scheduler*, %class.rust_crate_cache*, %class.rust_kernel*, i8*, %class.rust_task_list*, %struct.rust_cond*, i8*, %struct.rust_task*, i32, i32, i32, %class.timer, i32*, %class.array_list, %class.context, i32, i32, %class.memory_region, %"class.rust_task::wakeup_callback"*, i8, i8, %class.lock_and_signal }
+%struct.stk_seg = type { i32, i32, [0 x i8] }
+%struct.gc_alloc = type { %struct.gc_alloc*, %struct.gc_alloc*, i32, [0 x i8] }
+%struct.rust_scheduler = type { %class.rust_thread, %struct.rc_base, i32, %class.rust_log, i32, %class.rust_srv*, i8*, %class.rust_task_list, %class.rust_task_list, %class.rust_task_list, %class.rust_task_list, %class.rust_crate_cache, %struct.randctx, %class.rust_kernel*, i32, %class.hash_map, %class.hash_map.3, i32, %class.lock_and_signal, i32, %struct._opaque_pthread_attr_t, %struct.rust_env* }
+%class.rust_thread = type { i32 (...)**, i8, %struct._opaque_pthread_t* }
+%struct._opaque_pthread_t = type { i32, %struct.__darwin_pthread_handler_rec*, [596 x i8] }
+%struct.__darwin_pthread_handler_rec = type { {}*, i8*, %struct.__darwin_pthread_handler_rec* }
+%struct.rc_base = type { i32 }
+%class.rust_log = type { i32 (...)**, %class.rust_srv*, %struct.rust_scheduler*, i8 }
+%class.rust_srv = type { i32 (...)**, %struct.rust_env*, %class.memory_region }
+%struct.rust_env = type { i32, i32, i8*, i8, i8, i8* }
+%class.memory_region = type { i32 (...)**, %class.rust_srv*, %class.memory_region*, i32, %class.array_list.0, i8, i8, %class.lock_and_signal, i8 }
+%class.array_list.0 = type { i32, %"struct.memory_region::alloc_header"**, i32 }
+%"struct.memory_region::alloc_header" = type { i32, i32, i8*, [0 x i8] }
+%class.lock_and_signal = type { i32 (...)**, %struct._opaque_pthread_cond_t, %struct._opaque_pthread_mutex_t, %struct._opaque_pthread_t*, i8, i8 }
+%struct._opaque_pthread_cond_t = type { i32, [24 x i8] }
+%struct._opaque_pthread_mutex_t = type { i32, [40 x i8] }
+%class.rust_task_list = type { %class.indexed_list, %struct.rust_scheduler*, i8* }
+%class.indexed_list = type { i32 (...)**, %class.array_list }
+%class.array_list = type { i32, %struct.rust_task**, i32 }
+%class.rust_crate_cache = type { %struct.type_desc*, %struct.rust_scheduler*, i32 }
+%struct.type_desc = type { %struct.type_desc**, i32, i32, {}*, {}*, {}*, {}*, {}*, {}*, i32, {}*, %struct.UT_hash_handle, i32, [0 x %struct.type_desc*] }
+%struct.UT_hash_handle = type { %struct.UT_hash_table*, i8*, i8*, %struct.UT_hash_handle*, %struct.UT_hash_handle*, i8*, i32, i32 }
+%struct.UT_hash_table = type { %struct.UT_hash_bucket*, i32, i32, i32, %struct.UT_hash_handle*, i32, i32, i32, i32, i32 }
+%struct.UT_hash_bucket = type { %struct.UT_hash_handle*, i32, i32 }
+%struct.randctx = type { i32, [256 x i32], [256 x i32], i32, i32, i32 }
+%class.rust_kernel = type { i32 (...)**, %class.memory_region, %class.rust_log, %class.rust_srv*, %class.lock_and_signal, %class.array_list.4, %struct.randctx, i32, i32, i32, %struct.rust_env* }
+%class.array_list.4 = type { i32, %struct.rust_scheduler**, i32 }
+%class.hash_map = type { %"struct.hash_map<rust_task *, rust_task *>::map_entry"* }
+%"struct.hash_map<rust_task *, rust_task *>::map_entry" = type opaque
+%class.hash_map.3 = type { %"struct.hash_map<rust_port *, rust_port *>::map_entry"* }
+%"struct.hash_map<rust_port *, rust_port *>::map_entry" = type opaque
+%struct._opaque_pthread_attr_t = type { i32, [36 x i8] }
+%struct.rust_cond = type { i8 }
+%class.timer = type { i32 (...)**, i64, i64 }
+%class.context = type { %struct.registers_t, %class.context* }
+%struct.registers_t = type { i32, i32, i32, i32, i32, i32, i32, i32, i16, i16, i16, i16, i16, i16, i32, i32 }
+%"class.rust_task::wakeup_callback" = type { i32 (...)** }
+%struct.rust_vec = type { %struct.rc_base.5, i32, i32, i32, [0 x i8] }
+%struct.rc_base.5 = type { i32 }
+%struct.rust_ivec = type { i32, i32, %union.rust_ivec_payload }
+%union.rust_ivec_payload = type { %struct.rust_ivec_heap* }
+%struct.rust_ivec_heap = type { i32, [0 x i8] }
+%class.rust_port = type { i32, %class.rust_kernel*, %struct.rust_task*, i32, %class.ptr_vec, %class.ptr_vec.7, %class.rust_chan*, %class.lock_and_signal }
+%class.ptr_vec = type { %struct.rust_task*, i32, i32, %struct.rust_token** }
+%struct.rust_token = type opaque
+%class.ptr_vec.7 = type { %struct.rust_task*, i32, i32, %class.rust_chan** }
+%class.rust_chan = type { i32, %class.rust_kernel*, %struct.rust_task*, %class.rust_port*, i32, %class.circular_buffer }
+%class.circular_buffer = type { %class.rust_kernel*, i32, i32, i32, i32, i8* }
+
+@.str = private unnamed_addr constant [42 x i8] c"attempt to cast values of differing sizes\00", align 1
+@.str1 = private unnamed_addr constant [15 x i8] c"intrinsics.cpp\00", align 1
+
+define linkonce_odr void @rust_intrinsic_vec_len(%struct.rust_task* nocapture %task, i32* nocapture %retptr, %struct.type_desc* nocapture %ty, %struct.rust_vec* nocapture %v) nounwind {
+entry:
+  %fill = getelementptr inbounds %struct.rust_vec* %v, i32 0, i32 2
+  %tmp1 = load i32* %fill, align 4, !tbaa !0
+  %size = getelementptr inbounds %struct.type_desc* %ty, i32 0, i32 1
+  %tmp3 = load i32* %size, align 4, !tbaa !0
+  %div = udiv i32 %tmp1, %tmp3
+  store i32 %div, i32* %retptr, align 4, !tbaa !0
+  ret void
+}
+
+define linkonce_odr void @rust_intrinsic_ivec_len(%struct.rust_task* nocapture %task, i32* nocapture %retptr, %struct.type_desc* nocapture %ty, %struct.rust_ivec* nocapture %v) nounwind {
+entry:
+  %fill1 = getelementptr inbounds %struct.rust_ivec* %v, i32 0, i32 0
+  %tmp2 = load i32* %fill1, align 4, !tbaa !0
+  %tobool = icmp eq i32 %tmp2, 0
+  br i1 %tobool, label %if.else, label %if.end17
+
+if.else:                                          ; preds = %entry
+  %ptr = getelementptr inbounds %struct.rust_ivec* %v, i32 0, i32 2, i32 0
+  %tmp7 = load %struct.rust_ivec_heap** %ptr, align 4, !tbaa !3
+  %tobool8 = icmp eq %struct.rust_ivec_heap* %tmp7, null
+  br i1 %tobool8, label %if.end17, label %if.then9
+
+if.then9:                                         ; preds = %if.else
+  %fill14 = getelementptr inbounds %struct.rust_ivec_heap* %tmp7, i32 0, i32 0
+  %tmp15 = load i32* %fill14, align 4, !tbaa !0
+  br label %if.end17
+
+if.end17:                                         ; preds = %if.else, %entry, %if.then9
+  %fill.0 = phi i32 [ %tmp15, %if.then9 ], [ %tmp2, %entry ], [ 0, %if.else ]
+  %size = getelementptr inbounds %struct.type_desc* %ty, i32 0, i32 1
+  %tmp20 = load i32* %size, align 4, !tbaa !0
+  %div = udiv i32 %fill.0, %tmp20
+  store i32 %div, i32* %retptr, align 4, !tbaa !0
+  ret void
+}
+
+define linkonce_odr void @rust_intrinsic_ptr_offset(%struct.rust_task* nocapture %task, i8** nocapture %retptr, %struct.type_desc* nocapture %ty, i8* %ptr, i32 %count) nounwind {
+entry:
+  %size = getelementptr inbounds %struct.type_desc* %ty, i32 0, i32 1
+  %tmp1 = load i32* %size, align 4, !tbaa !0
+  %mul = mul i32 %tmp1, %count
+  %arrayidx = getelementptr inbounds i8* %ptr, i32 %mul
+  store i8* %arrayidx, i8** %retptr, align 4, !tbaa !3
+  ret void
+}
+
+define linkonce_odr void @rust_intrinsic_cast(%struct.rust_task* %task, i8* nocapture %retptr, %struct.type_desc* nocapture %t1, %struct.type_desc* nocapture %t2, i8* nocapture %src) {
+entry:
+  %size = getelementptr inbounds %struct.type_desc* %t1, i32 0, i32 1
+  %tmp1 = load i32* %size, align 4, !tbaa !0
+  %size3 = getelementptr inbounds %struct.type_desc* %t2, i32 0, i32 1
+  %tmp4 = load i32* %size3, align 4, !tbaa !0
+  %cmp = icmp eq i32 %tmp1, %tmp4
+  br i1 %cmp, label %if.end, label %if.then
+
+if.then:                                          ; preds = %entry
+  tail call void @upcall_fail(%struct.rust_task* %task, i8* getelementptr inbounds ([42 x i8]* @.str, i32 0, i32 0), i8* getelementptr inbounds ([15 x i8]* @.str1, i32 0, i32 0), i32 45)
+  br label %return
+
+if.end:                                           ; preds = %entry
+  tail call void @llvm.memmove.p0i8.p0i8.i32(i8* %retptr, i8* %src, i32 %tmp1, i32 1, i1 false)
+  br label %return
+
+return:                                           ; preds = %if.end, %if.then
+  ret void
+}
+
+declare void @upcall_fail(%struct.rust_task*, i8*, i8*, i32)
+
+declare void @llvm.memmove.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i32, i1) nounwind
+
+define linkonce_odr void @rust_intrinsic_addr_of(%struct.rust_task* nocapture %task, i8** nocapture %retptr, %struct.type_desc* nocapture %ty, i8* %valptr) nounwind {
+entry:
+  store i8* %valptr, i8** %retptr, align 4, !tbaa !3
+  ret void
+}
+
+define linkonce_odr void @rust_intrinsic_recv(%struct.rust_task* %task, i8** nocapture %retptr, %struct.type_desc* nocapture %ty, %class.rust_port* %port) {
+entry:
+  %tmp2 = load i8** %retptr, align 4, !tbaa !3
+  %0 = bitcast i8* %tmp2 to i32*
+  tail call void @port_recv(%struct.rust_task* %task, i32* %0, %class.rust_port* %port)
+  ret void
+}
+
+declare void @port_recv(%struct.rust_task*, i32*, %class.rust_port*)
+
+!0 = metadata !{metadata !"long", metadata !1}
+!1 = metadata !{metadata !"omnipotent char", metadata !2}
+!2 = metadata !{metadata !"Simple C/C++ TBAA", null}
+!3 = metadata !{metadata !"any pointer", metadata !1}
diff --git a/src/rt/intrinsics/intrinsics.x86_64.ll.in b/src/rt/intrinsics/intrinsics.x86_64.ll.in
new file mode 100644
index 00000000000..d18c1f7c9e4
--- /dev/null
+++ b/src/rt/intrinsics/intrinsics.x86_64.ll.in
@@ -0,0 +1,237 @@
+; ModuleID = 'src/rt/intrinsics/intrinsics.cpp'
+; target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
+target triple = "@CFG_TARGET_TRIPLE@"
+
+%0 = type { i64, %struct.rust_task**, i64 }
+%1 = type { %"struct.hash_map<long, rust_task *>::map_entry"* }
+%class.array_list = type { i64, %"struct.memory_region::alloc_header"**, i64 }
+%class.boxed_region = type { %class.memory_region*, %struct.rust_opaque_box* }
+%class.circular_buffer = type { %class.rust_kernel*, i64, i64, i64, i64, i8* }
+%class.context = type { %struct.registers_t, %class.context*, [8 x i8] }
+%"class.debug::task_debug_info" = type { %"class.std::map" }
+%class.hash_map = type { %"struct.hash_map<long, rust_port *>::map_entry"* }
+%class.indexed_list = type { i32 (...)**, %0 }
+%class.lock_and_signal = type { i32 (...)**, %struct._opaque_pthread_cond_t, %struct._opaque_pthread_attr_t, %struct._opaque_pthread_t* }
+%class.memory_region = type { i32 (...)**, %class.rust_srv*, %class.memory_region*, i32, %class.array_list, i8, i8, %class.lock_and_signal }
+%class.rust_crate_cache = type { %struct.type_desc*, %struct.rust_hashable_dict*, %struct.rust_task_thread*, i64 }
+%class.rust_kernel = type { %class.memory_region, %class.rust_log, %class.rust_srv*, %class.lock_and_signal, i64, i64, %1, %class.lock_and_signal, i32, %class.lock_and_signal, i64, %"class.std::map", %"class.std::vector", %struct.rust_env* }
+%class.rust_log = type { i32 (...)**, %class.rust_srv*, %struct.rust_task_thread*, i8 }
+%class.rust_obstack = type { %struct.rust_obstack_chunk*, %struct.rust_task* }
+%class.rust_port = type { i64, i64, %class.rust_kernel*, %struct.rust_task*, i64, %class.circular_buffer, %class.lock_and_signal }
+%class.rust_port_selector = type { %class.rust_port**, i64, %class.lock_and_signal }
+%class.rust_scheduler = type opaque
+%class.rust_srv = type { i32 (...)**, %struct.rust_env*, %class.memory_region }
+%class.rust_task_list = type { %class.indexed_list, %struct.rust_task_thread*, i8* }
+%class.rust_thread = type { i32 (...)**, %struct._opaque_pthread_t*, i64 }
+%"class.std::_Rb_tree" = type { %"struct.std::_Rb_tree<long, std::pair<const long, rust_scheduler *>, std::_Select1st<std::pair<const long, rust_scheduler *> >, std::less<long>, std::allocator<std::pair<const long, rust_scheduler *> > >::_Rb_tree_impl" }
+%"class.std::map" = type { %"class.std::_Rb_tree" }
+%"class.std::vector" = type { %"struct.std::_Vector_base" }
+%struct.UT_hash_bucket = type { %struct.UT_hash_handle*, i32, i32 }
+%struct.UT_hash_handle = type { %struct.UT_hash_table*, i8*, i8*, %struct.UT_hash_handle*, %struct.UT_hash_handle*, i8*, i32, i32 }
+%struct.UT_hash_table = type { %struct.UT_hash_bucket*, i32, i32, i32, %struct.UT_hash_handle*, i64, i32, i32, i32, i32 }
+%struct.__darwin_pthread_handler_rec = type { void (i8*)*, i8*, %struct.__darwin_pthread_handler_rec* }
+%struct._opaque_pthread_attr_t = type { i64, [56 x i8] }
+%struct._opaque_pthread_cond_t = type { i64, [40 x i8] }
+%struct._opaque_pthread_t = type { i64, %struct.__darwin_pthread_handler_rec*, [1168 x i8] }
+%struct.chan_handle = type { i64, i64 }
+%"struct.hash_map<long, rust_port *>::map_entry" = type opaque
+%"struct.hash_map<long, rust_task *>::map_entry" = type opaque
+%"struct.memory_region::alloc_header" = type { i8 }
+%struct.randctx = type { i64, [256 x i64], [256 x i64], i64, i64, i64 }
+%struct.registers_t = type { [22 x i64] }
+%struct.rust_box = type opaque
+%struct.rust_env = type { i64, i64, i64, i8*, i8, i8, i8* }
+%struct.rust_fn = type { i64*, %struct.rust_box* }
+%struct.rust_hashable_dict = type { %struct.UT_hash_handle, [0 x i8*] }
+%struct.rust_obstack_chunk = type { %struct.rust_obstack_chunk*, i64, i64, i64, [0 x i8] }
+%struct.rust_opaque_box = type { i64, %struct.type_desc*, %struct.rust_opaque_box*, %struct.rust_opaque_box* }
+%struct.rust_shape_tables = type { i8*, i8* }
+%struct.rust_task = type { i64, i64, i8, %struct.chan_handle, [8 x i8], %class.context, %struct.stk_seg*, i64, %class.rust_scheduler*, %struct.rust_task_thread*, %class.rust_crate_cache*, %class.rust_kernel*, i8*, %class.rust_task_list*, %"struct.memory_region::alloc_header"*, i8*, %struct.rust_task*, i32, i64, i64*, %class.memory_region, %class.boxed_region, i8, i8, %class.lock_and_signal, %class.hash_map, %class.rust_obstack, i32, %"class.debug::task_debug_info", i64, i8, i8, %struct.stk_seg*, i64, i64, %class.rust_port_selector }
+%struct.rust_task_thread = type { %class.rust_thread, i64, %class.rust_log, i32, %class.rust_srv*, i8*, %class.rust_task_list, %class.rust_task_list, %class.rust_task_list, %class.rust_task_list, %class.rust_crate_cache, %struct.randctx, %class.rust_kernel*, %class.rust_scheduler*, i32, i32, %class.lock_and_signal, i64, %struct._opaque_pthread_attr_t, %struct.rust_env*, %class.context, i8, %struct.stk_seg*, %struct.stk_seg*, [8 x i8] }
+%struct.rust_vec = type { i64, i64, [0 x i8] }
+%"struct.std::_Rb_tree<long, std::pair<const long, rust_scheduler *>, std::_Select1st<std::pair<const long, rust_scheduler *> >, std::less<long>, std::allocator<std::pair<const long, rust_scheduler *> > >::_Rb_tree_impl" = type { %"struct.memory_region::alloc_header", %"struct.std::_Rb_tree_node_base", i64 }
+%"struct.std::_Rb_tree_node_base" = type { i32, %"struct.std::_Rb_tree_node_base"*, %"struct.std::_Rb_tree_node_base"*, %"struct.std::_Rb_tree_node_base"* }
+%"struct.std::_Vector_base" = type { %"struct.std::_Vector_base<long, std::allocator<long> >::_Vector_impl" }
+%"struct.std::_Vector_base<long, std::allocator<long> >::_Vector_impl" = type { i64*, i64*, i64* }
+%struct.stk_seg = type { %struct.stk_seg*, %struct.stk_seg*, i64, i32, i64, [0 x i8] }
+%struct.type_desc = type { %struct.type_desc**, i64, i64, void (i8*, i8*, %struct.type_desc**, i8*)*, void (i8*, i8*, %struct.type_desc**, i8*)*, void (i8*, i8*, %struct.type_desc**, i8*)*, i8*, void (i8*, i8*, %struct.type_desc**, i8*)*, void (i8*, i8*, %struct.type_desc**, i8*)*, i64, i8*, i8*, %struct.rust_shape_tables*, i64, i64, %struct.UT_hash_handle, i64, [0 x %struct.type_desc*] }
+
+define void @rust_intrinsic_vec_len(i64* nocapture %retptr, i8* nocapture %env, %struct.type_desc* nocapture %ty, %struct.rust_vec** nocapture %vp) nounwind {
+  %1 = load %struct.rust_vec** %vp, align 8
+  %2 = getelementptr inbounds %struct.rust_vec* %1, i64 0, i32 0
+  %3 = load i64* %2, align 8
+  %4 = getelementptr inbounds %struct.type_desc* %ty, i64 0, i32 1
+  %5 = load i64* %4, align 8
+  %6 = udiv i64 %3, %5
+  store i64 %6, i64* %retptr, align 8
+  ret void
+}
+
+define void @rust_intrinsic_ptr_offset(i8** nocapture %retptr, i8* nocapture %env, %struct.type_desc* nocapture %ty, i8* %ptr, i64 %count) nounwind {
+  %1 = getelementptr inbounds %struct.type_desc* %ty, i64 0, i32 1
+  %2 = load i64* %1, align 8
+  %3 = mul i64 %2, %count
+  %4 = getelementptr inbounds i8* %ptr, i64 %3
+  store i8* %4, i8** %retptr, align 8
+  ret void
+}
+
+define void @rust_intrinsic_cast(i8* nocapture %retptr, i8* nocapture %env, %struct.type_desc* nocapture %t1, %struct.type_desc* nocapture %t2, i8* nocapture %src) nounwind {
+  %1 = getelementptr inbounds %struct.type_desc* %t1, i64 0, i32 1
+  %2 = load i64* %1, align 8
+  tail call void @llvm.memmove.p0i8.p0i8.i64(i8* %retptr, i8* %src, i64 %2, i32 1, i1 false)
+  ret void
+}
+
+declare void @llvm.memmove.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i32, i1) nounwind
+
+define void @rust_intrinsic_addr_of(i8** nocapture %retptr, i8* nocapture %env, %struct.type_desc* nocapture %ty, i8* %valptr) nounwind {
+  store i8* %valptr, i8** %retptr, align 8
+  ret void
+}
+
+define void @rust_intrinsic_call_with_retptr(i8** %retptr, i8* nocapture %env, %struct.type_desc* nocapture %ty, %struct.rust_fn* nocapture %recvfn) {
+  %1 = getelementptr inbounds %struct.rust_fn* %recvfn, i64 0, i32 0
+  %2 = load i64** %1, align 8
+  %3 = bitcast i64* %2 to void (i8**, i8*, i8**)*
+  %4 = getelementptr inbounds %struct.rust_fn* %recvfn, i64 0, i32 1
+  %5 = load %struct.rust_box** %4, align 8
+  %6 = bitcast %struct.rust_box* %5 to i8*
+  tail call void %3(i8** null, i8* %6, i8** %retptr)
+  ret void
+}
+
+define void @rust_intrinsic_get_type_desc(i8** nocapture %retptr, i8* nocapture %env, %struct.type_desc* %ty) nounwind {
+  %ty.c = bitcast %struct.type_desc* %ty to i8*
+  store i8* %ty.c, i8** %retptr, align 8
+  ret void
+}
+
+define void @rust_intrinsic_task_yield(i8** nocapture %retptr, i8* nocapture %env, %struct.rust_task* %task, i8* %killed) {
+  tail call void @rust_task_yield(%struct.rust_task* %task, i8* %killed)
+  ret void
+}
+
+declare void @rust_task_yield(%struct.rust_task*, i8*)
+
+define void @rust_intrinsic_memmove(i8* nocapture %retptr, i8* nocapture %env, %struct.type_desc* nocapture %ty, i8* nocapture %dst, i8* nocapture %src, i64 %count) nounwind {
+  %1 = getelementptr inbounds %struct.type_desc* %ty, i64 0, i32 1
+  %2 = load i64* %1, align 8
+  %3 = mul i64 %2, %count
+  tail call void @llvm.memmove.p0i8.p0i8.i64(i8* %dst, i8* %src, i64 %3, i32 1, i1 false)
+  ret void
+}
+
+define void @rust_intrinsic_memcpy(i8* nocapture %retptr, i8* nocapture %env, %struct.type_desc* nocapture %ty, i8* nocapture %dst, i8* nocapture %src, i64 %count) nounwind {
+  %1 = getelementptr inbounds %struct.type_desc* %ty, i64 0, i32 1
+  %2 = load i64* %1, align 8
+  %3 = mul i64 %2, %count
+  tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst, i8* %src, i64 %3, i32 1, i1 false)
+  ret void
+}
+
+declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i32, i1) nounwind
+
+define void @rust_intrinsic_leak(i8* nocapture %retptr, i8* nocapture %env, %struct.type_desc* nocapture %ty, i8* nocapture %thing) nounwind readnone {
+  ret void
+}
+
+define void @upcall_intrinsic_vec_push(%struct.rust_vec** nocapture %vp, %struct.type_desc* nocapture %elt_ty, i8* nocapture %elt) {
+; <label>:0
+  %1 = load %struct.rust_vec** %vp, align 8
+  %2 = getelementptr inbounds %struct.rust_vec* %1, i64 0, i32 0
+  %3 = load i64* %2, align 8
+  %4 = getelementptr inbounds %struct.type_desc* %elt_ty, i64 0, i32 1
+  %5 = load i64* %4, align 8
+  %6 = add i64 %5, %3
+  %7 = getelementptr inbounds %struct.rust_vec* %1, i64 0, i32 1
+  %8 = load i64* %7, align 8
+  %9 = icmp ult i64 %8, %6
+  br i1 %9, label %10, label %_Z16reserve_vec_fastPP8rust_vecm.exit
+
+; <label>:10                                      ; preds = %0
+  %11 = add i64 %6, -1
+  %12 = lshr i64 %11, 1
+  %13 = or i64 %12, %11
+  %14 = lshr i64 %13, 2
+  %15 = or i64 %14, %13
+  %16 = lshr i64 %15, 4
+  %17 = or i64 %16, %15
+  %18 = lshr i64 %17, 8
+  %19 = or i64 %18, %17
+  %20 = lshr i64 %19, 16
+  %21 = or i64 %20, %19
+  %22 = lshr i64 %21, 32
+  %23 = or i64 %22, %21
+  %24 = add i64 %23, 1
+  %25 = add i64 %23, 17
+  %26 = bitcast %struct.rust_vec* %1 to i8*
+  %27 = tail call i8* @upcall_shared_realloc(i8* %26, i64 %25)
+  %28 = bitcast i8* %27 to %struct.rust_vec*
+  store %struct.rust_vec* %28, %struct.rust_vec** %vp, align 8
+  %29 = getelementptr inbounds i8* %27, i64 8
+  %30 = bitcast i8* %29 to i64*
+  store i64 %24, i64* %30, align 8
+  %.pr = load i64* %4, align 8
+  %.pre = load %struct.rust_vec** %vp, align 8
+  %.phi.trans.insert = getelementptr inbounds %struct.rust_vec* %.pre, i64 0, i32 0
+  %.pre4 = load i64* %.phi.trans.insert, align 8
+  br label %_Z16reserve_vec_fastPP8rust_vecm.exit
+
+_Z16reserve_vec_fastPP8rust_vecm.exit:            ; preds = %0, %10
+  %31 = phi i64 [ %3, %0 ], [ %.pre4, %10 ]
+  %32 = phi %struct.rust_vec* [ %1, %0 ], [ %.pre, %10 ]
+  %33 = phi i64 [ %5, %0 ], [ %.pr, %10 ]
+  %34 = getelementptr inbounds %struct.rust_vec* %32, i64 0, i32 0
+  %35 = getelementptr inbounds %struct.rust_vec* %32, i64 0, i32 2, i64 %31
+  tail call void @llvm.memmove.p0i8.p0i8.i64(i8* %35, i8* %elt, i64 %33, i32 1, i1 false)
+  %36 = getelementptr inbounds %struct.type_desc* %elt_ty, i64 0, i32 3
+  %37 = load void (i8*, i8*, %struct.type_desc**, i8*)** %36, align 8
+  %38 = icmp eq void (i8*, i8*, %struct.type_desc**, i8*)* %37, null
+  br i1 %38, label %_ZL13copy_elementsP9type_descPvS1_m.exit, label %39
+
+; <label>:39                                      ; preds = %_Z16reserve_vec_fastPP8rust_vecm.exit
+  %40 = load i64* %4, align 8
+  %41 = getelementptr inbounds %struct.type_desc* %elt_ty, i64 0, i32 0
+  %42 = load %struct.type_desc*** %41, align 8
+  %43 = icmp sgt i64 %33, 0
+  br i1 %43, label %.lr.ph.i.preheader, label %_ZL13copy_elementsP9type_descPvS1_m.exit
+
+.lr.ph.i.preheader:                               ; preds = %39
+  %scevgep = getelementptr %struct.rust_vec* %32, i64 1, i32 0
+  %scevgep2 = bitcast i64* %scevgep to i8*
+  br label %.lr.ph.i
+
+.lr.ph.i:                                         ; preds = %.lr.ph.i.preheader, %.lr.ph.i
+  %indvar.i = phi i64 [ %indvar.next.i, %.lr.ph.i ], [ 0, %.lr.ph.i.preheader ]
+  %tmp = mul i64 %40, %indvar.i
+  %tmp2.i = add i64 %40, %tmp
+  %tmp3 = add i64 %31, %tmp
+  %p.01.i = getelementptr i8* %scevgep2, i64 %tmp3
+  tail call void %37(i8* null, i8* null, %struct.type_desc** %42, i8* %p.01.i)
+  %44 = icmp slt i64 %tmp2.i, %33
+  %indvar.next.i = add i64 %indvar.i, 1
+  br i1 %44, label %.lr.ph.i, label %_ZL13copy_elementsP9type_descPvS1_m.exit
+
+_ZL13copy_elementsP9type_descPvS1_m.exit:         ; preds = %.lr.ph.i, %_Z16reserve_vec_fastPP8rust_vecm.exit, %39
+  %45 = load i64* %4, align 8
+  %46 = load i64* %34, align 8
+  %47 = add i64 %46, %45
+  store i64 %47, i64* %34, align 8
+  ret void
+}
+
+define void @upcall_vec_push(%struct.rust_vec** nocapture %vp, %struct.type_desc* nocapture %elt_ty, i8* nocapture %elt) {
+  tail call void @upcall_intrinsic_vec_push(%struct.rust_vec** %vp, %struct.type_desc* %elt_ty, i8* %elt)
+  ret void
+}
+
+define void @rust_intrinsic_frame_address(i8** nocapture %p) nounwind {
+  %1 = tail call i8* @llvm.frameaddress(i32 1)
+  store i8* %1, i8** %p, align 8
+  ret void
+}
+
+declare i8* @llvm.frameaddress(i32) nounwind readnone
+
+declare i8* @upcall_shared_realloc(i8*, i64)
diff --git a/src/rustc/back/link.rs b/src/rustc/back/link.rs
index cf01d9507f2..7b0e14b1da6 100644
--- a/src/rustc/back/link.rs
+++ b/src/rustc/back/link.rs
@@ -30,6 +30,69 @@ fn llvm_err(sess: session, msg: str) -> ! unsafe {
     } else { sess.fatal(msg + ": " + str::unsafe::from_c_str(cstr)); }
 }
 
+fn load_intrinsics_bc(sess: session) -> option<ModuleRef> {
+    let path = alt filesearch::search(
+        sess.filesearch,
+        bind filesearch::pick_file("intrinsics.bc", _)) {
+      option::some(path) { path }
+      option::none {
+        sess.warn("couldn't find intrinsics.bc");
+        ret option::none;
+      }
+    };
+    let membuf = str::as_c_str(path, {|buf|
+        llvm::LLVMRustCreateMemoryBufferWithContentsOfFile(buf)
+                                   });
+    if membuf as uint == 0u {
+        llvm_err(sess, "installation problem: couldn't open " + path);
+    }
+    let llintrinsicsmod = llvm::LLVMRustParseBitcode(membuf);
+    llvm::LLVMDisposeMemoryBuffer(membuf);
+    if llintrinsicsmod as uint == 0u {
+        sess.warn("couldn't parse intrinsics.bc");
+        ret option::none;
+    }
+
+    ret option::some(llintrinsicsmod);
+}
+
+fn load_intrinsics_ll(sess: session) -> ModuleRef {
+    let path = alt filesearch::search(
+        sess.filesearch,
+        bind filesearch::pick_file("intrinsics.ll", _)) {
+      option::some(path) { path }
+      option::none { sess.fatal("couldn't find intrinsics.ll") }
+    };
+    let llintrinsicsmod = str::as_c_str(path, { |buf|
+        llvm::LLVMRustParseAssemblyFile(buf)
+                                        });
+    if llintrinsicsmod as uint == 0u {
+        llvm_err(sess, "couldn't parse intrinsics.ll");
+    }
+    ret llintrinsicsmod;
+}
+
+fn link_intrinsics(sess: session, llmod: ModuleRef) {
+    let llintrinsicsmod = {
+        alt load_intrinsics_bc(sess) {
+          option::some(m) { m }
+          option::none {
+            // When the bitcode format changes we can't parse a .bc
+            // file produced with a newer LLVM (as happens when stage0
+            // is trying to build against a new LLVM revision), in
+            // that case we'll try to parse the assembly.
+            sess.warn("couldn't parse intrinsics.bc, trying intrinsics.ll");
+            load_intrinsics_ll(sess)
+          }
+        }
+    };
+    let linkres = llvm::LLVMLinkModules(llmod, llintrinsicsmod);
+    llvm::LLVMDisposeModule(llintrinsicsmod);
+    if linkres == False {
+        llvm_err(sess, "couldn't link the module with the intrinsics");
+    }
+}
+
 mod write {
     fn is_object_or_assembly_or_exe(ot: output_type) -> bool {
         if ot == output_type_assembly || ot == output_type_object ||
@@ -52,6 +115,7 @@ mod write {
     fn run_passes(sess: session, llmod: ModuleRef, output: str) {
         let opts = sess.opts;
         if opts.time_llvm_passes { llvm::LLVMRustEnableTimePasses(); }
+        link_intrinsics(sess, llmod);
         let mut pm = mk_pass_manager();
         let td = mk_target_data(
             sess.targ_cfg.target_strs.data_layout);
diff --git a/src/rustc/back/upcall.rs b/src/rustc/back/upcall.rs
index 43c924b9595..3d8b051638b 100644
--- a/src/rustc/back/upcall.rs
+++ b/src/rustc/back/upcall.rs
@@ -17,6 +17,7 @@ type upcalls =
      shared_realloc: ValueRef,
      mark: ValueRef,
      vec_grow: ValueRef,
+     vec_push: ValueRef,
      str_concat: ValueRef,
      cmp_type: ValueRef,
      log_type: ValueRef,
@@ -40,6 +41,7 @@ fn declare_upcalls(targ_cfg: @session::config,
     }
     let d = bind decl(llmod, "upcall_", _, _, _);
     let dv = bind decl(llmod, "upcall_", _, _, T_void());
+    let dvi = bind decl(llmod, "upcall_intrinsic_", _, _, T_void());
 
     let int_t = T_int(targ_cfg);
     let size_t = T_size_t(targ_cfg);
@@ -64,6 +66,10 @@ fn declare_upcalls(targ_cfg: @session::config,
               d("mark", [T_ptr(T_i8())], int_t),
           vec_grow:
               dv("vec_grow", [T_ptr(T_ptr(opaque_vec_t)), int_t]),
+          vec_push:
+              dvi("vec_push",
+                [T_ptr(T_ptr(opaque_vec_t)), T_ptr(tydesc_type),
+                 T_ptr(T_i8())]),
           str_concat:
               d("str_concat", [T_ptr(opaque_vec_t), T_ptr(opaque_vec_t)],
                 T_ptr(opaque_vec_t)),
diff --git a/src/rustc/front/attr.rs b/src/rustc/front/attr.rs
index 39b42ba2d78..8c991517d88 100644
--- a/src/rustc/front/attr.rs
+++ b/src/rustc/front/attr.rs
@@ -237,9 +237,12 @@ fn native_abi(attrs: [ast::attribute]) -> either<str, ast::native_abi> {
       option::none {
         either::right(ast::native_abi_cdecl)
       }
-      option::some("rust-builtin") | option::some("rust-intrinsic") {
+      option::some("rust-intrinsic") {
         either::right(ast::native_abi_rust_intrinsic)
       }
+      option::some("rust-builtin") {
+        either::right(ast::native_abi_rust_builtin)
+      }
       option::some("cdecl") {
         either::right(ast::native_abi_cdecl)
       }
diff --git a/src/rustc/metadata/common.rs b/src/rustc/metadata/common.rs
index 8a6b0eb30b2..00aa26969d7 100644
--- a/src/rustc/metadata/common.rs
+++ b/src/rustc/metadata/common.rs
@@ -68,6 +68,7 @@ const tag_mod_impl: uint = 0x30u;
 
 const tag_item_method: uint = 0x31u;
 const tag_impl_iface: uint = 0x32u;
+const tag_item_is_intrinsic: uint = 0x33u;
 
 // discriminator value for variants
 const tag_disr_val: uint = 0x34u;
diff --git a/src/rustc/metadata/csearch.rs b/src/rustc/metadata/csearch.rs
index e43b7aa7ff3..02b506f7070 100644
--- a/src/rustc/metadata/csearch.rs
+++ b/src/rustc/metadata/csearch.rs
@@ -26,6 +26,7 @@ export get_type;
 export get_impl_iface;
 export get_impl_method;
 export get_item_path;
+export item_is_intrinsic;
 export maybe_get_item_ast, found_ast, found, found_parent, not_found;
 
 fn get_symbol(cstore: cstore::cstore, def: ast::def_id) -> str {
@@ -189,6 +190,11 @@ fn get_class_method(cstore: cstore::cstore, def: ast::def_id, mname: str)
     decoder::get_class_method(cdata, def.node, mname)
 }
 
+fn item_is_intrinsic(cstore: cstore::cstore, def: ast::def_id) -> bool {
+    let cdata = cstore::get_crate_data(cstore, def.crate);
+    decoder::item_is_intrinsic(cdata, def.node)
+}
+
 // Local Variables:
 // mode: rust
 // fill-column: 78;
diff --git a/src/rustc/metadata/decoder.rs b/src/rustc/metadata/decoder.rs
index 97a77dd71d3..cf1947a96dc 100644
--- a/src/rustc/metadata/decoder.rs
+++ b/src/rustc/metadata/decoder.rs
@@ -41,6 +41,7 @@ export get_item_path;
 export maybe_find_item; // sketchy
 export item_type; // sketchy
 export maybe_get_item_ast;
+export item_is_intrinsic;
 
 // Used internally by astencode:
 export translate_def_id;
@@ -308,6 +309,13 @@ fn get_class_method(cdata: cmd, id: ast::node_id, name: str) -> ast::def_id {
     }
 }
 
+fn item_is_intrinsic(cdata: cmd, id: ast::node_id) -> bool {
+    let mut intrinsic = false;
+    ebml::tagged_docs(lookup_item(id, cdata.data), tag_item_is_intrinsic,
+                      {|_i| intrinsic = true;});
+    intrinsic
+}
+
 fn get_symbol(data: @[u8], id: ast::node_id) -> str {
     ret item_symbol(lookup_item(id, data));
 }
diff --git a/src/rustc/metadata/encoder.rs b/src/rustc/metadata/encoder.rs
index 3e9e5d842ab..69086d4698b 100644
--- a/src/rustc/metadata/encoder.rs
+++ b/src/rustc/metadata/encoder.rs
@@ -676,8 +676,12 @@ fn encode_info_for_native_item(ecx: @encode_ctxt, ebml_w: ebml::writer,
         encode_def_id(ebml_w, local_def(nitem.id));
         encode_family(ebml_w, purity_fn_family(fn_decl.purity));
         encode_type_param_bounds(ebml_w, ecx, tps);
-        encode_type(ecx, ebml_w, node_id_to_type(ecx.ccx.tcx, nitem.id));
         if abi == native_abi_rust_intrinsic {
+            ebml_w.start_tag(tag_item_is_intrinsic);
+            ebml_w.end_tag();
+        }
+        encode_type(ecx, ebml_w, node_id_to_type(ecx.ccx.tcx, nitem.id));
+        if abi == native_abi_rust_builtin {
             astencode::encode_inlined_item(ecx, ebml_w, path,
                                            ii_native(nitem));
         } else {
diff --git a/src/rustc/middle/ast_map.rs b/src/rustc/middle/ast_map.rs
index d2186a27ee8..7e3de19c432 100644
--- a/src/rustc/middle/ast_map.rs
+++ b/src/rustc/middle/ast_map.rs
@@ -92,7 +92,7 @@ fn map_decoded_item(sess: session, map: map, path: path, ii: inlined_item) {
     alt ii {
       ii_item(i) { /* fallthrough */ }
       ii_native(i) {
-        cx.map.insert(i.id, node_native_item(i, native_abi_rust_intrinsic,
+        cx.map.insert(i.id, node_native_item(i, native_abi_rust_builtin,
                                              @path));
       }
       ii_method(impl_did, m) {
diff --git a/src/rustc/middle/lint.rs b/src/rustc/middle/lint.rs
index 3ccbaed873c..806237ca59c 100644
--- a/src/rustc/middle/lint.rs
+++ b/src/rustc/middle/lint.rs
@@ -124,7 +124,7 @@ fn check_ctypes(tcx: ty::ctxt, crate: @ast::crate) {
     fn check_item(tcx: ty::ctxt, it: @ast::item) {
         alt it.node {
           ast::item_native_mod(nmod) if attr::native_abi(it.attrs) !=
-              either::right(ast::native_abi_rust_intrinsic) {
+              either::right(ast::native_abi_rust_builtin) {
             for ni in nmod.items {
                 alt ni.node {
                   ast::native_item_fn(decl, tps) {
diff --git a/src/rustc/middle/trans/base.rs b/src/rustc/middle/trans/base.rs
index 1ddeff6a04b..0252802d6a7 100644
--- a/src/rustc/middle/trans/base.rs
+++ b/src/rustc/middle/trans/base.rs
@@ -1801,7 +1801,9 @@ enum callee_env {
 type lval_maybe_callee = {bcx: block,
                           val: ValueRef,
                           kind: lval_kind,
-                          env: callee_env};
+                          env: callee_env,
+                          // Tydescs to pass. Only used to call intrinsics
+                          tds: option<[ValueRef]>};
 
 fn null_env_ptr(bcx: block) -> ValueRef {
     C_null(T_opaque_box_ptr(bcx.ccx()))
@@ -1820,7 +1822,7 @@ fn lval_temp(bcx: block, val: ValueRef) -> lval_result {
 
 fn lval_no_env(bcx: block, val: ValueRef, kind: lval_kind)
     -> lval_maybe_callee {
-    ret {bcx: bcx, val: val, kind: kind, env: is_closure};
+    ret {bcx: bcx, val: val, kind: kind, env: is_closure, tds: none};
 }
 
 fn trans_external_path(ccx: @crate_ctxt, did: ast::def_id, t: ty::t)
@@ -1907,7 +1909,7 @@ fn make_mono_id(ccx: @crate_ctxt, item: ast::def_id, substs: [ty::t],
 fn monomorphic_fn(ccx: @crate_ctxt, fn_id: ast::def_id, real_substs: [ty::t],
                   vtables: option<typeck::vtable_res>,
                   ref_id: option<ast::node_id>)
-    -> {val: ValueRef, must_cast: bool} {
+    -> {val: ValueRef, must_cast: bool, intrinsic: bool} {
     let _icx = ccx.insn_ctxt("monomorphic_fn");
     let mut must_cast = false;
     let substs = vec::map(real_substs, {|t|
@@ -1925,7 +1927,7 @@ fn monomorphic_fn(ccx: @crate_ctxt, fn_id: ast::def_id, real_substs: [ty::t],
     }
     alt ccx.monomorphized.find(hash_id) {
       some(val) {
-        ret {val: val, must_cast: must_cast};
+        ret {val: val, must_cast: must_cast, intrinsic: false};
       }
       none {}
     }
@@ -1947,12 +1949,13 @@ fn monomorphic_fn(ccx: @crate_ctxt, fn_id: ast::def_id, real_substs: [ty::t],
       }
       ast_map::node_variant(v, _, pt) { (pt, v.node.name) }
       ast_map::node_method(m, _, pt) { (pt, m.ident) }
-      ast_map::node_native_item(i, ast::native_abi_rust_intrinsic, pt)
+      ast_map::node_native_item(i, ast::native_abi_rust_builtin, pt)
       { (pt, i.ident) }
       ast_map::node_native_item(_, abi, _) {
         // Natives don't have to be monomorphized.
         ret {val: get_item_val(ccx, fn_id.node),
-             must_cast: true};
+             must_cast: true,
+             intrinsic: abi == ast::native_abi_rust_intrinsic};
       }
       ast_map::node_ctor(i, _) {
         alt check ccx.tcx.items.get(i.id) {
@@ -1981,8 +1984,8 @@ fn monomorphic_fn(ccx: @crate_ctxt, fn_id: ast::def_id, real_substs: [ty::t],
         trans_fn(ccx, pt, d, body, lldecl, no_self, psubsts, d_id, none);
       }
       ast_map::node_native_item(i, _, _) {
-        native::trans_intrinsic(ccx, lldecl, i, pt, option::get(psubsts),
-                                ref_id);
+        native::trans_builtin(ccx, lldecl, i, pt, option::get(psubsts),
+                              ref_id);
       }
       ast_map::node_variant(v, enum_item, _) {
         let tvs = ty::enum_variants(ccx.tcx, local_def(enum_item.id));
@@ -2011,7 +2014,7 @@ fn monomorphic_fn(ccx: @crate_ctxt, fn_id: ast::def_id, real_substs: [ty::t],
         }
       }
     }
-    {val: lldecl, must_cast: must_cast}
+    {val: lldecl, must_cast: must_cast, intrinsic: false}
 }
 
 fn maybe_instantiate_inline(ccx: @crate_ctxt, fn_id: ast::def_id)
@@ -2075,6 +2078,33 @@ fn maybe_instantiate_inline(ccx: @crate_ctxt, fn_id: ast::def_id)
     }
 }
 
+fn lval_intrinsic_fn(bcx: block, val: ValueRef, tys: [ty::t],
+                     id: ast::node_id) -> lval_maybe_callee {
+    let _icx = bcx.insn_ctxt("lval_intrinsic_fn");
+    fn add_tydesc_params(ccx: @crate_ctxt, llfty: TypeRef, n: uint)
+        -> TypeRef {
+        let out_ty = llvm::LLVMGetReturnType(llfty);
+        let n_args = llvm::LLVMCountParamTypes(llfty);
+        let args = vec::from_elem(n_args as uint, 0 as TypeRef);
+        unsafe { llvm::LLVMGetParamTypes(llfty, vec::unsafe::to_ptr(args)); }
+        T_fn(vec::slice(args, 0u, first_real_arg) +
+             vec::from_elem(n, T_ptr(ccx.tydesc_type)) +
+             vec::tailn(args, first_real_arg), out_ty)
+    }
+
+    let mut bcx = bcx;
+    let ccx = bcx.ccx();
+    let tds = vec::map(tys, {|t|
+        let mut ti = none, td = get_tydesc(bcx.ccx(), t, ti);
+        lazily_emit_all_tydesc_glue(ccx, ti);
+        td
+    });
+    let llfty = type_of_fn_from_ty(ccx, node_id_type(bcx, id));
+    let val = PointerCast(bcx, val, T_ptr(add_tydesc_params(
+        ccx, llfty, tys.len())));
+    {bcx: bcx, val: val, kind: owned, env: null_env, tds: some(tds)}
+}
+
 fn lval_static_fn(bcx: block, fn_id: ast::def_id, id: ast::node_id)
     -> lval_maybe_callee {
     let _icx = bcx.insn_ctxt("lval_static_fn");
@@ -2098,13 +2128,14 @@ fn lval_static_fn_inner(bcx: block, fn_id: ast::def_id, id: ast::node_id,
     } else { fn_id };
 
     if fn_id.crate == ast::local_crate && tys.len() > 0u {
-        let mut {val, must_cast} =
+        let mut {val, must_cast, intrinsic} =
             monomorphic_fn(ccx, fn_id, tys, vtables, some(id));
+        if intrinsic { ret lval_intrinsic_fn(bcx, val, tys, id); }
         if must_cast {
             val = PointerCast(bcx, val, T_ptr(type_of_fn_from_ty(
                 ccx, node_id_type(bcx, id))));
         }
-        ret {bcx: bcx, val: val, kind: owned, env: null_env};
+        ret {bcx: bcx, val: val, kind: owned, env: null_env, tds: none};
     }
 
     let mut val = if fn_id.crate == ast::local_crate {
@@ -2115,6 +2146,11 @@ fn lval_static_fn_inner(bcx: block, fn_id: ast::def_id, id: ast::node_id,
         trans_external_path(ccx, fn_id, tpt.ty)
     };
     if tys.len() > 0u {
+        // This is supposed to be an external native function.
+        // Unfortunately, I found no easy/cheap way to assert that.
+        if csearch::item_is_intrinsic(ccx.sess.cstore, fn_id) {
+            ret lval_intrinsic_fn(bcx, val, tys, id);
+        }
         val = PointerCast(bcx, val, T_ptr(type_of_fn_from_ty(
             ccx, node_id_type(bcx, id))));
     }
@@ -2131,7 +2167,7 @@ fn lval_static_fn_inner(bcx: block, fn_id: ast::def_id, id: ast::node_id,
         }
     }
 
-    ret {bcx: bcx, val: val, kind: owned, env: null_env};
+    ret {bcx: bcx, val: val, kind: owned, env: null_env, tds: none};
 }
 
 fn lookup_discriminant(ccx: @crate_ctxt, vid: ast::def_id) -> ValueRef {
@@ -2589,7 +2625,7 @@ enum call_args {
 //  - new_fn_ctxt
 //  - trans_args
 fn trans_args(cx: block, llenv: ValueRef, args: call_args, fn_ty: ty::t,
-              dest: dest)
+              dest: dest, always_valid_retptr: bool)
     -> {bcx: block, args: [ValueRef], retslot: ValueRef} {
     let _icx = cx.insn_ctxt("trans_args");
     let mut temp_cleanups = [];
@@ -2603,7 +2639,7 @@ fn trans_args(cx: block, llenv: ValueRef, args: call_args, fn_ty: ty::t,
     // Arg 0: Output pointer.
     let llretslot = alt dest {
       ignore {
-        if ty::type_is_nil(retty) {
+        if ty::type_is_nil(retty) && !always_valid_retptr {
             llvm::LLVMGetUndef(T_ptr(T_nil()))
         } else {
             let {bcx: cx, val} = alloc_ty(bcx, retty);
@@ -2697,10 +2733,15 @@ fn trans_call_inner(in_cx: block, fn_expr_ty: ty::t, ret_ty: ty::t,
         };
 
         let args_res = {
-            trans_args(bcx, llenv, args, fn_expr_ty, dest)
+            trans_args(bcx, llenv, args, fn_expr_ty, dest,
+                       option::is_some(f_res.tds))
         };
         bcx = args_res.bcx;
         let mut llargs = args_res.args;
+        option::may(f_res.tds) {|vals|
+            llargs = vec::slice(llargs, 0u, first_real_arg) + vals +
+                vec::tailn(llargs, first_real_arg);
+        }
 
         let llretslot = args_res.retslot;
 
diff --git a/src/rustc/middle/trans/closure.rs b/src/rustc/middle/trans/closure.rs
index a10eda9932a..153cc079d6b 100644
--- a/src/rustc/middle/trans/closure.rs
+++ b/src/rustc/middle/trans/closure.rs
@@ -416,6 +416,7 @@ fn trans_bind_1(cx: block, outgoing_fty: ty::t,
                 args: [option<@ast::expr>], pair_ty: ty::t,
                 dest: dest) -> block {
     let _icx = cx.insn_ctxt("closure::trans_bind1");
+    assert option::is_none(f_res.tds);
     let ccx = cx.ccx();
     let mut bound: [@ast::expr] = [];
     for argopt: option<@ast::expr> in args {
diff --git a/src/rustc/middle/trans/impl.rs b/src/rustc/middle/trans/impl.rs
index 0f9c5cf4759..3fa4dfc80b0 100644
--- a/src/rustc/middle/trans/impl.rs
+++ b/src/rustc/middle/trans/impl.rs
@@ -79,7 +79,7 @@ fn trans_vtable_callee(bcx: block, env: callee_env, vtable: ValueRef,
     let vtable = PointerCast(bcx, vtable,
                              T_ptr(T_array(T_ptr(llfty), n_method + 1u)));
     let mptr = Load(bcx, GEPi(bcx, vtable, [0, n_method as int]));
-    {bcx: bcx, val: mptr, kind: owned, env: env}
+    {bcx: bcx, val: mptr, kind: owned, env: env, tds: none}
 }
 
 fn method_with_name(ccx: @crate_ctxt, impl_id: ast::def_id,
diff --git a/src/rustc/middle/trans/native.rs b/src/rustc/middle/trans/native.rs
index 97d5a361c96..be10c8d0e78 100644
--- a/src/rustc/middle/trans/native.rs
+++ b/src/rustc/middle/trans/native.rs
@@ -16,7 +16,7 @@ import std::map::hashmap;
 import util::ppaux::ty_to_str;
 
 export link_name, trans_native_mod, register_crust_fn, trans_crust_fn,
-       decl_native_fn, trans_intrinsic;
+       decl_native_fn, trans_builtin;
 
 enum x86_64_reg_class {
     no_class,
@@ -730,7 +730,11 @@ fn trans_native_mod(ccx: @crate_ctxt,
     }
 
     let mut cc = alt abi {
-      ast::native_abi_rust_intrinsic { ret; }
+      ast::native_abi_rust_intrinsic {
+        for item in native_mod.items { get_item_val(ccx, item.id); }
+        ret;
+      }
+      ast::native_abi_rust_builtin { ret; }
       ast::native_abi_cdecl { lib::llvm::CCallConv }
       ast::native_abi_stdcall { lib::llvm::X86StdcallCallConv }
     };
@@ -752,9 +756,9 @@ fn trans_native_mod(ccx: @crate_ctxt,
     }
 }
 
-fn trans_intrinsic(ccx: @crate_ctxt, decl: ValueRef, item: @ast::native_item,
-                   path: ast_map::path, substs: param_substs,
-                   ref_id: option<ast::node_id>) {
+fn trans_builtin(ccx: @crate_ctxt, decl: ValueRef, item: @ast::native_item,
+                 path: ast_map::path, substs: param_substs,
+                 ref_id: option<ast::node_id>) {
     let fcx = new_fn_ctxt_w_id(ccx, path, decl, item.id, none,
                                some(substs), some(item.span));
     let bcx = top_scope_block(fcx, none), lltop = bcx.llbb;
@@ -1005,5 +1009,28 @@ fn abi_of_native_fn(ccx: @crate_ctxt, i: @ast::native_item)
 
 fn decl_native_fn(ccx: @crate_ctxt, i: @ast::native_item,
                   pth: ast_map::path) -> ValueRef {
-    register_fn(ccx, i.span, pth, i.id)
+    let _icx = ccx.insn_ctxt("native::decl_native_fn");
+    alt i.node {
+      ast::native_item_fn(_, _) {
+        let node_type = ty::node_id_to_type(ccx.tcx, i.id);
+        alt abi_of_native_fn(ccx, i) {
+          ast::native_abi_rust_intrinsic {
+            // For intrinsics: link the function directly to the intrinsic
+            // function itself.
+            let fn_type = type_of_fn_from_ty(ccx, node_type);
+            let ri_name = "rust_intrinsic_" + native::link_name(i);
+            ccx.item_symbols.insert(i.id, ri_name);
+            get_extern_fn(ccx.externs, ccx.llmod, ri_name,
+                          lib::llvm::CCallConv, fn_type)
+          }
+          ast::native_abi_cdecl | ast::native_abi_stdcall |
+          ast::native_abi_rust_builtin {
+            // For true external functions: create a rust wrapper
+            // and link to that.  The rust wrapper will handle
+            // switching to the C stack.
+            register_fn(ccx, i.span, pth, i.id)
+          }
+        }
+      }
+    }
 }
diff --git a/src/rustc/middle/trans/type_use.rs b/src/rustc/middle/trans/type_use.rs
index 8120056b13a..24b6f9cf572 100644
--- a/src/rustc/middle/trans/type_use.rs
+++ b/src/rustc/middle/trans/type_use.rs
@@ -52,7 +52,11 @@ fn type_uses_for(ccx: @crate_ctxt, fn_id: def_id, n_tps: uint)
       _ {}
     }
 
+    // FIXME handle external native functions in a more efficient way
     if fn_id_loc.crate != local_crate {
+        if csearch::item_is_intrinsic(ccx.sess.cstore, fn_id) {
+            uint::range(0u, n_tps) {|n| cx.uses[n] |= use_tydesc;}
+        }
         let uses = vec::from_mut(cx.uses);
         ccx.type_use_cache.insert(fn_id, uses);
         ret uses;
@@ -69,6 +73,8 @@ fn type_uses_for(ccx: @crate_ctxt, fn_id: def_id, n_tps: uint)
       }
       ast_map::node_native_item(i@@{node: native_item_fn(_, _), _}, abi, _) {
         if abi == native_abi_rust_intrinsic {
+            uint::range(0u, n_tps) {|n| cx.uses[n] |= use_tydesc;}
+        } else if abi == native_abi_rust_builtin {
             let flags = alt check i.ident {
               "size_of" | "align_of" | "init" |
               "reinterpret_cast" { use_repr }
diff --git a/src/rustc/middle/typeck.rs b/src/rustc/middle/typeck.rs
index 6e0b39373a1..4743d6556b5 100644
--- a/src/rustc/middle/typeck.rs
+++ b/src/rustc/middle/typeck.rs
@@ -948,8 +948,8 @@ mod collect {
           ast::item_mod(_) {}
           ast::item_native_mod(m) {
             if front::attr::native_abi(it.attrs) ==
-               either::right(ast::native_abi_rust_intrinsic) {
-                for item in m.items { check_intrinsic_type(tcx, item); }
+               either::right(ast::native_abi_rust_builtin) {
+                for item in m.items { check_builtin_type(tcx, item); }
             }
           }
           ast::item_enum(variants, ty_params) {
@@ -1414,7 +1414,7 @@ mod writeback {
     }
 }
 
-fn check_intrinsic_type(tcx: ty::ctxt, it: @ast::native_item) {
+fn check_builtin_type(tcx: ty::ctxt, it: @ast::native_item) {
     fn param(tcx: ty::ctxt, n: uint) -> ty::t {
         ty::mk_param(tcx, n, local_def(0))
     }
@@ -1432,7 +1432,7 @@ fn check_intrinsic_type(tcx: ty::ctxt, it: @ast::native_item) {
       "addr_of" { (1u, [arg(ast::by_ref, param(tcx, 0u))],
                    ty::mk_imm_ptr(tcx, param(tcx, 0u))) }
       other {
-        tcx.sess.span_err(it.span, "unrecognized intrinsic function: `" +
+        tcx.sess.span_err(it.span, "unrecognized builtin function: `" +
                           other + "`");
         ret;
       }
@@ -1444,11 +1444,11 @@ fn check_intrinsic_type(tcx: ty::ctxt, it: @ast::native_item) {
     let i_ty = ty_of_native_item(tcx, m_collect, it);
     let i_n_tps = (*i_ty.bounds).len();
     if i_n_tps != n_tps {
-        tcx.sess.span_err(it.span, #fmt("intrinsic has wrong number \
+        tcx.sess.span_err(it.span, #fmt("builtin function has wrong number \
                                          of type parameters. found %u, \
                                          expected %u", i_n_tps, n_tps));
     } else if !ty::same_type(tcx, i_ty.ty, fty) {
-        tcx.sess.span_err(it.span, #fmt("intrinsic has wrong type. \
+        tcx.sess.span_err(it.span, #fmt("builtin function has wrong type. \
                                          expected %s", ty_to_str(tcx, fty)));
     }
 }
diff --git a/src/rustc/syntax/ast.rs b/src/rustc/syntax/ast.rs
index 1f0b40925bc..0776ec3dfbd 100644
--- a/src/rustc/syntax/ast.rs
+++ b/src/rustc/syntax/ast.rs
@@ -557,6 +557,7 @@ type _mod = {view_items: [@view_item], items: [@item]};
 #[auto_serialize]
 enum native_abi {
     native_abi_rust_intrinsic,
+    native_abi_rust_builtin,
     native_abi_cdecl,
     native_abi_stdcall,
 }