3 files changed, 47 insertions, 26 deletions
diff --git a/compiler/rustc_codegen_llvm/src/builder.rs b/compiler/rustc_codegen_llvm/src/builder.rs
index e1609e31c07..677a9cd3e90 100644
--- a/compiler/rustc_codegen_llvm/src/builder.rs
+++ b/compiler/rustc_codegen_llvm/src/builder.rs
@@ -31,7 +31,9 @@ use tracing::{debug, instrument};
 use crate::abi::FnAbiLlvmExt;
 use crate::common::Funclet;
 use crate::context::{CodegenCx, SimpleCx};
-use crate::llvm::{self, AtomicOrdering, AtomicRmwBinOp, BasicBlock, False, Metadata, True};
+use crate::llvm::{
+    self, AtomicOrdering, AtomicRmwBinOp, BasicBlock, False, GEPNoWrapFlags, Metadata, True,
+};
 use crate::type_::Type;
 use crate::type_of::LayoutLlvmExt;
 use crate::value::Value;
@@ -910,13 +912,14 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
 
     fn gep(&mut self, ty: &'ll Type, ptr: &'ll Value, indices: &[&'ll Value]) -> &'ll Value {
         unsafe {
-            llvm::LLVMBuildGEP2(
+            llvm::LLVMBuildGEPWithNoWrapFlags(
                 self.llbuilder,
                 ty,
                 ptr,
                 indices.as_ptr(),
                 indices.len() as c_uint,
                 UNNAMED,
+                GEPNoWrapFlags::default(),
             )
         }
     }
@@ -928,13 +931,33 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
         indices: &[&'ll Value],
     ) -> &'ll Value {
         unsafe {
-            llvm::LLVMBuildInBoundsGEP2(
+            llvm::LLVMBuildGEPWithNoWrapFlags(
+                self.llbuilder,
+                ty,
+                ptr,
+                indices.as_ptr(),
+                indices.len() as c_uint,
+                UNNAMED,
+                GEPNoWrapFlags::InBounds,
+            )
+        }
+    }
+
+    fn inbounds_nuw_gep(
+        &mut self,
+        ty: &'ll Type,
+        ptr: &'ll Value,
+        indices: &[&'ll Value],
+    ) -> &'ll Value {
+        unsafe {
+            llvm::LLVMBuildGEPWithNoWrapFlags(
                 self.llbuilder,
                 ty,
                 ptr,
                 indices.as_ptr(),
                 indices.len() as c_uint,
                 UNNAMED,
+                GEPNoWrapFlags::InBounds | GEPNoWrapFlags::NUW,
             )
         }
     }
diff --git a/compiler/rustc_codegen_llvm/src/intrinsic.rs b/compiler/rustc_codegen_llvm/src/intrinsic.rs
index f68365f6c69..dfbb5bc1731 100644
--- a/compiler/rustc_codegen_llvm/src/intrinsic.rs
+++ b/compiler/rustc_codegen_llvm/src/intrinsic.rs
@@ -127,15 +127,14 @@ fn get_simple_intrinsic<'ll>(
         sym::truncf64 => "llvm.trunc.f64",
         sym::truncf128 => "llvm.trunc.f128",
 
-        sym::rintf16 => "llvm.rint.f16",
-        sym::rintf32 => "llvm.rint.f32",
-        sym::rintf64 => "llvm.rint.f64",
-        sym::rintf128 => "llvm.rint.f128",
-
-        sym::nearbyintf16 => "llvm.nearbyint.f16",
-        sym::nearbyintf32 => "llvm.nearbyint.f32",
-        sym::nearbyintf64 => "llvm.nearbyint.f64",
-        sym::nearbyintf128 => "llvm.nearbyint.f128",
+        // We could use any of `rint`, `nearbyint`, or `roundeven`
+        // for this -- they are all identical in semantics when
+        // assuming the default FP environment.
+        // `rint` is what we used for $forever.
+        sym::round_ties_even_f16 => "llvm.rint.f16",
+        sym::round_ties_even_f32 => "llvm.rint.f32",
+        sym::round_ties_even_f64 => "llvm.rint.f64",
+        sym::round_ties_even_f128 => "llvm.rint.f128",
 
         sym::roundf16 => "llvm.round.f16",
         sym::roundf32 => "llvm.round.f32",
@@ -144,11 +143,6 @@ fn get_simple_intrinsic<'ll>(
 
         sym::ptr_mask => "llvm.ptrmask",
 
-        sym::roundevenf16 => "llvm.roundeven.f16",
-        sym::roundevenf32 => "llvm.roundeven.f32",
-        sym::roundevenf64 => "llvm.roundeven.f64",
-        sym::roundevenf128 => "llvm.roundeven.f128",
-
         _ => return None,
     };
     Some(cx.get_intrinsic(llvm_name))
diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
index 3b0187b9d37..da91e6edbcf 100644
--- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
@@ -954,6 +954,17 @@ bitflags! {
     }
 }
 
+// These values **must** match with LLVMGEPNoWrapFlags
+bitflags! {
+    #[repr(transparent)]
+    #[derive(Default)]
+    pub struct GEPNoWrapFlags : c_uint {
+        const InBounds = 1 << 0;
+        const NUSW = 1 << 1;
+        const NUW = 1 << 2;
+    }
+}
+
 unsafe extern "C" {
     pub type ModuleBuffer;
 }
@@ -1454,21 +1465,14 @@ unsafe extern "C" {
 
     pub(crate) fn LLVMBuildStore<'a>(B: &Builder<'a>, Val: &'a Value, Ptr: &'a Value) -> &'a Value;
 
-    pub(crate) fn LLVMBuildGEP2<'a>(
-        B: &Builder<'a>,
-        Ty: &'a Type,
-        Pointer: &'a Value,
-        Indices: *const &'a Value,
-        NumIndices: c_uint,
-        Name: *const c_char,
-    ) -> &'a Value;
-    pub(crate) fn LLVMBuildInBoundsGEP2<'a>(
+    pub(crate) fn LLVMBuildGEPWithNoWrapFlags<'a>(
         B: &Builder<'a>,
         Ty: &'a Type,
         Pointer: &'a Value,
         Indices: *const &'a Value,
         NumIndices: c_uint,
         Name: *const c_char,
+        Flags: GEPNoWrapFlags,
     ) -> &'a Value;
 
     // Casts