Revert "rt: More work on morestack"

This reverts commit 68aff2ad6d55a051e9347aa38f945d114f282691.

1 files changed, 21 insertions, 98 deletions

diff --git a/src/rt/arch/i386/morestack.S b/src/rt/arch/i386/morestack.S
index ec356ea91c6..2f5987a4350 100644
--- a/src/rt/arch/i386/morestack.S
+++ b/src/rt/arch/i386/morestack.S
@@ -2,117 +2,40 @@
 
 // __morestack
 //
-// LLVM generates a call to this to allocate more stack space in a function
+// LLVM generates a call to this to allocate more stack space in a functiono
 // prolog when we run out.
 
 #if defined(__APPLE__) || defined(_WIN32)
-#define RUST_NEW_STACK          _rust_new_stack
-#define RUST_DEL_STACK          _rust_del_stack
-#define RUST_GET_PREV_STACK     _rust_get_prev_stack
-#define RUST_GET_TASK           _rust_get_task
-#define UPCALL_ALLOC_C_STACK    _upcall_alloc_c_stack
-#define UPCALL_CALL_C_STACK     _upcall_call_c_stack
-#define MORESTACK               ___morestack
+#define RUST_NEW_STACK      _rust_new_stack
+#define RUST_DEL_STACK      _rust_del_stack
+#define MORESTACK           ___morestack
 #else
-#define RUST_NEW_STACK          rust_new_stack
-#define RUST_DEL_STACK          rust_del_stack
-#define RUST_GET_PREV_STACK     rust_get_prev_stack
-#define RUST_GET_TASK           rust_get_task
-#define UPCALL_ALLOC_C_STACK    upcall_alloc_c_stack
-#define UPCALL_CALL_C_STACK     upcall_call_c_stack
-#define MORESTACK               __morestack
+#define RUST_NEW_STACK      rust_new_stack
+#define RUST_DEL_STACK      rust_del_stack
+#define MORESTACK           __morestack
 #endif
 
-#ifdef __APPLE__
-#define ALIGNMENT               4
-#else
-#define ALIGNMENT               8
-#endif
-
-#define RETURN_OFFSET   7
-
 .globl RUST_NEW_STACK
 .globl RUST_DEL_STACK
-.globl RUST_GET_PREV_STACK
-.globl RUST_GET_TASK
-.globl UPCALL_ALLOC_C_STACK
-.globl UPCALL_CALL_C_STACK
+
 .globl MORESTACK
 
 MORESTACK:
-
-    // Sanity check to make sure that there is a currently-running task.
-    subl $12,%esp
-    calll RUST_GET_TASK
-    testl %eax,%eax
-    jz L$bail
-
-    subl $12,%esp
-    pushl $12
-    calll UPCALL_ALLOC_C_STACK
-    movl %eax,%edx
-
-                            // C stack              | esp+12
-                            // ---------------------+-------------------------
-    movl 20(%esp),%eax      //                      | ra stksz argsz x ra args
-    movl %eax,8(%edx)       //              argsz > | ra stksz argsz x ra args
-    leal 32(%esp),%eax      //                argsz | ra stksz argsz x ra args
-    movl %eax,4(%edx)       //         argp > argsz | ra stksz argsz x ra args
-    movl 16(%esp),%eax      //           argp argsz | ra stksz argsz x ra args
-    movl %eax,(%edx)        //   stksz > argp argsz | ra stksz argsz x ra args
-
-    calll L$pic_ref_pt_0
-L$pic_ref_pt_0:
-    popl %eax
-
-    movl rust_new_stack_sym-L$pic_ref_pt_0(%eax),%eax
-    movl %eax,(%esp)
-    movl %edx,4(%esp)
-    calll UPCALL_CALL_C_STACK
-
-    movl 16(%esp),%edx          // Grab the return pointer.
-    addl $RETURN_OFFSET,%edx    // Skip past the `add esp,4` and the `ret`.
-
-    movl %eax,%esp          // Switch stacks.
-    subl $12,%esp           // Align the stack.
+    pushl 8(%esp)           //              argsz > ra stksz argsz x x ra args
+    leal 28(%esp),%eax      //                argsz ra stksz argsz x x ra args
+    pushl %eax              //         argp > argsz ra stksz argsz x x ra args
+    pushl 12(%esp)          //   stksz > argp argsz ra stksz argsz x x ra args
+    calll RUST_NEW_STACK
+    addl $12,%esp           //                      ra stksz argsz x x ra args
+
+    movl (%esp),%edx        // Grab the return pointer.
+    incl %edx               // Skip past the `ret`.
+    movl %eax,%esp          // Switch to the new stack.
     calll *%edx             // Re-enter the function that called us.
 
     // Now the function that called us has returned, so we need to delete the
     // old stack space.
-
-    calll RUST_GET_PREV_STACK
-    movl %eax,%esp          // Switch back to the old stack.
-
-    movl $0,(%esp)
-    calll UPCALL_ALLOC_C_STACK
-
-    calll L$pic_ref_pt_1
-L$pic_ref_pt_1:
-    popl %edx
-
-    movl rust_del_stack_sym-L$pic_ref_pt_1(%edx),%edx
-    movl %edx,(%esp)
-    movl %eax,4(%esp)
-    calll UPCALL_CALL_C_STACK
-
-    addl $16,%esp
-    retl $16 + ALIGNMENT    //                      ra stksz argsz x ra args
-
-L$bail:
-    movl 12(%esp),%edx
-    addl $RETURN_OFFSET,%edx
-    addl $12+16,%esp
-    jmpl *%edx
-
-#ifdef __APPLE__
-
-	.section	__IMPORT,__pointers,non_lazy_symbol_pointers
-rust_new_stack_sym:
-    .indirect_symbol RUST_NEW_STACK
-    .long 0
-rust_del_stack_sym:
-    .indirect_symbol RUST_DEL_STACK
-    .long 0
-
-#endif
+    calll RUST_DEL_STACK
+    movl %eax,%esp
+    retl $8                 //                      ra stksz argsz x x ra args