diff options
Diffstat (limited to 'compiler/rustc_codegen_llvm/src/builder.rs')
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/builder.rs | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/compiler/rustc_codegen_llvm/src/builder.rs b/compiler/rustc_codegen_llvm/src/builder.rs index fca43a0d8..77dd15ef4 100644 --- a/compiler/rustc_codegen_llvm/src/builder.rs +++ b/compiler/rustc_codegen_llvm/src/builder.rs @@ -365,11 +365,14 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> { Int(I64) => "llvm.ssub.with.overflow.i64", Int(I128) => "llvm.ssub.with.overflow.i128", - Uint(U8) => "llvm.usub.with.overflow.i8", - Uint(U16) => "llvm.usub.with.overflow.i16", - Uint(U32) => "llvm.usub.with.overflow.i32", - Uint(U64) => "llvm.usub.with.overflow.i64", - Uint(U128) => "llvm.usub.with.overflow.i128", + Uint(_) => { + // Emit sub and icmp instead of llvm.usub.with.overflow. LLVM considers these + // to be the canonical form. It will attempt to reform llvm.usub.with.overflow + // in the backend if profitable. + let sub = self.sub(lhs, rhs); + let cmp = self.icmp(IntPredicate::IntULT, lhs, rhs); + return (sub, cmp); + } _ => unreachable!(), }, @@ -553,15 +556,15 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> { } fn write_operand_repeatedly( - mut self, + &mut self, cg_elem: OperandRef<'tcx, &'ll Value>, count: u64, dest: PlaceRef<'tcx, &'ll Value>, - ) -> Self { + ) { let zero = self.const_usize(0); let count = self.const_usize(count); - let start = dest.project_index(&mut self, zero).llval; - let end = dest.project_index(&mut self, count).llval; + let start = dest.project_index(self, zero).llval; + let end = dest.project_index(self, count).llval; let header_bb = self.append_sibling_block("repeat_loop_header"); let body_bb = self.append_sibling_block("repeat_loop_body"); @@ -589,7 +592,7 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> { body_bx.br(header_bb); header_bx.add_incoming_to_phi(current, next, body_bb); - Self::build(self.cx, next_bb) + *self = Self::build(self.cx, next_bb); } fn range_metadata(&mut self, load: &'ll Value, range: WrappingRange) { |