diff options
| author | bors <bors@rust-lang.org> | 2024-02-21 09:43:33 +0000 |
|---|---|---|
| committer | bors <bors@rust-lang.org> | 2024-02-21 09:43:33 +0000 |
| commit | bb8b11e67dd5833e503d47694d815eec41418675 (patch) | |
| tree | b21f60156d6e725c5311316e2c7b4677c45f2ee3 /compiler/rustc_codegen_cranelift | |
| parent | 7168c13579a550f2c47f7eea22f5e226a436cd00 (diff) | |
| parent | cc73b71e8e568c6421a23fc2954a86e1947aac66 (diff) | |
| download | rust-bb8b11e67dd5833e503d47694d815eec41418675.tar.gz rust-bb8b11e67dd5833e503d47694d815eec41418675.zip | |
Auto merge of #120718 - saethlin:reasonable-fast-math, r=nnethercote
Add "algebraic" fast-math intrinsics, based on fast-math ops that cannot return poison Setting all of LLVM's fast-math flags makes our fast-math intrinsics very dangerous, because some inputs are UB. This set of flags permits common algebraic transformations, but according to the [LangRef](https://llvm.org/docs/LangRef.html#fastmath), only the flags `nnan` (no nans) and `ninf` (no infs) can produce poison. And this uses the algebraic float ops to fix https://github.com/rust-lang/rust/issues/120720 cc `@orlp`
Diffstat (limited to 'compiler/rustc_codegen_cranelift')
| -rw-r--r-- | compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs index 476752c7230..199d5df29e7 100644 --- a/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs +++ b/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs @@ -1152,17 +1152,26 @@ fn codegen_regular_intrinsic_call<'tcx>( ret.write_cvalue(fx, ret_val); } - sym::fadd_fast | sym::fsub_fast | sym::fmul_fast | sym::fdiv_fast | sym::frem_fast => { + sym::fadd_fast + | sym::fsub_fast + | sym::fmul_fast + | sym::fdiv_fast + | sym::frem_fast + | sym::fadd_algebraic + | sym::fsub_algebraic + | sym::fmul_algebraic + | sym::fdiv_algebraic + | sym::frem_algebraic => { intrinsic_args!(fx, args => (x, y); intrinsic); let res = crate::num::codegen_float_binop( fx, match intrinsic { - sym::fadd_fast => BinOp::Add, - sym::fsub_fast => BinOp::Sub, - sym::fmul_fast => BinOp::Mul, - sym::fdiv_fast => BinOp::Div, - sym::frem_fast => BinOp::Rem, + sym::fadd_fast | sym::fadd_algebraic => BinOp::Add, + sym::fsub_fast | sym::fsub_algebraic => BinOp::Sub, + sym::fmul_fast | sym::fmul_algebraic => BinOp::Mul, + sym::fdiv_fast | sym::fdiv_algebraic => BinOp::Div, + sym::frem_fast | sym::frem_algebraic => BinOp::Rem, _ => unreachable!(), }, x, |