diff options
Diffstat (limited to 'compiler/rustc_codegen_llvm/src/builder.rs')
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/builder.rs | 150 |
1 files changed, 140 insertions, 10 deletions
diff --git a/compiler/rustc_codegen_llvm/src/builder.rs b/compiler/rustc_codegen_llvm/src/builder.rs index 264d43c6d46..677a9cd3e90 100644 --- a/compiler/rustc_codegen_llvm/src/builder.rs +++ b/compiler/rustc_codegen_llvm/src/builder.rs @@ -4,7 +4,7 @@ use std::{iter, ptr}; pub(crate) mod autodiff; -use libc::{c_char, c_uint}; +use libc::{c_char, c_uint, size_t}; use rustc_abi as abi; use rustc_abi::{Align, Size, WrappingRange}; use rustc_codegen_ssa::MemFlags; @@ -29,13 +29,15 @@ use smallvec::SmallVec; use tracing::{debug, instrument}; use crate::abi::FnAbiLlvmExt; -use crate::attributes; use crate::common::Funclet; use crate::context::{CodegenCx, SimpleCx}; -use crate::llvm::{self, AtomicOrdering, AtomicRmwBinOp, BasicBlock, False, 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; +use crate::{attributes, llvm_util}; #[must_use] pub(crate) struct GenericBuilder<'a, 'll, CX: Borrow<SimpleCx<'ll>>> { @@ -333,6 +335,50 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> { } } + fn switch_with_weights( + &mut self, + v: Self::Value, + else_llbb: Self::BasicBlock, + else_is_cold: bool, + cases: impl ExactSizeIterator<Item = (u128, Self::BasicBlock, bool)>, + ) { + if self.cx.sess().opts.optimize == rustc_session::config::OptLevel::No { + self.switch(v, else_llbb, cases.map(|(val, dest, _)| (val, dest))); + return; + } + + let id_str = "branch_weights"; + let id = unsafe { + llvm::LLVMMDStringInContext2(self.cx.llcx, id_str.as_ptr().cast(), id_str.len()) + }; + + // For switch instructions with 2 targets, the `llvm.expect` intrinsic is used. + // This function handles switch instructions with more than 2 targets and it needs to + // emit branch weights metadata instead of using the intrinsic. + // The values 1 and 2000 are the same as the values used by the `llvm.expect` intrinsic. + let cold_weight = unsafe { llvm::LLVMValueAsMetadata(self.cx.const_u32(1)) }; + let hot_weight = unsafe { llvm::LLVMValueAsMetadata(self.cx.const_u32(2000)) }; + let weight = + |is_cold: bool| -> &Metadata { if is_cold { cold_weight } else { hot_weight } }; + + let mut md: SmallVec<[&Metadata; 16]> = SmallVec::with_capacity(cases.len() + 2); + md.push(id); + md.push(weight(else_is_cold)); + + let switch = + unsafe { llvm::LLVMBuildSwitch(self.llbuilder, v, else_llbb, cases.len() as c_uint) }; + for (on_val, dest, is_cold) in cases { + let on_val = self.const_uint_big(self.val_ty(v), on_val); + unsafe { llvm::LLVMAddCase(switch, on_val, dest) } + md.push(weight(is_cold)); + } + + unsafe { + let md_node = llvm::LLVMMDNodeInContext2(self.cx.llcx, md.as_ptr(), md.len() as size_t); + self.cx.set_metadata(switch, llvm::MD_prof, md_node); + } + } + fn invoke( &mut self, llty: &'ll Type, @@ -421,6 +467,37 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> { unchecked_umul(x, y) => LLVMBuildNUWMul, } + fn unchecked_suadd(&mut self, a: &'ll Value, b: &'ll Value) -> &'ll Value { + unsafe { + let add = llvm::LLVMBuildAdd(self.llbuilder, a, b, UNNAMED); + if llvm::LLVMIsAInstruction(add).is_some() { + llvm::LLVMSetNUW(add, True); + llvm::LLVMSetNSW(add, True); + } + add + } + } + fn unchecked_susub(&mut self, a: &'ll Value, b: &'ll Value) -> &'ll Value { + unsafe { + let sub = llvm::LLVMBuildSub(self.llbuilder, a, b, UNNAMED); + if llvm::LLVMIsAInstruction(sub).is_some() { + llvm::LLVMSetNUW(sub, True); + llvm::LLVMSetNSW(sub, True); + } + sub + } + } + fn unchecked_sumul(&mut self, a: &'ll Value, b: &'ll Value) -> &'ll Value { + unsafe { + let mul = llvm::LLVMBuildMul(self.llbuilder, a, b, UNNAMED); + if llvm::LLVMIsAInstruction(mul).is_some() { + llvm::LLVMSetNUW(mul, True); + llvm::LLVMSetNSW(mul, True); + } + mul + } + } + fn or_disjoint(&mut self, a: &'ll Value, b: &'ll Value) -> &'ll Value { unsafe { let or = llvm::LLVMBuildOr(self.llbuilder, a, b, UNNAMED); @@ -531,7 +608,7 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> { fn to_immediate_scalar(&mut self, val: Self::Value, scalar: abi::Scalar) -> Self::Value { if scalar.is_bool() { - return self.trunc(val, self.cx().type_i1()); + return self.unchecked_utrunc(val, self.cx().type_i1()); } val } @@ -543,7 +620,8 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> { unsafe { let alloca = llvm::LLVMBuildAlloca(bx.llbuilder, ty, UNNAMED); llvm::LLVMSetAlignment(alloca, align.bytes() as c_uint); - alloca + // Cast to default addrspace if necessary + llvm::LLVMBuildPointerCast(bx.llbuilder, alloca, self.cx().type_ptr(), UNNAMED) } } @@ -552,7 +630,8 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> { let alloca = llvm::LLVMBuildArrayAlloca(self.llbuilder, self.cx().type_i8(), size, UNNAMED); llvm::LLVMSetAlignment(alloca, align.bytes() as c_uint); - alloca + // Cast to default addrspace if necessary + llvm::LLVMBuildPointerCast(self.llbuilder, alloca, self.cx().type_ptr(), UNNAMED) } } @@ -669,10 +748,12 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> { let load = self.load(llty, place.val.llval, place.val.align); if let abi::BackendRepr::Scalar(scalar) = place.layout.backend_repr { scalar_load_metadata(self, load, scalar, place.layout, Size::ZERO); + self.to_immediate_scalar(load, scalar) + } else { + load } - load }); - OperandValue::Immediate(self.to_immediate(llval, place.layout)) + OperandValue::Immediate(llval) } else if let abi::BackendRepr::ScalarPair(a, b) = place.layout.backend_repr { let b_offset = a.size(self).align_to(b.align(self).abi); @@ -831,13 +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(), ) } } @@ -849,13 +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, ) } } @@ -865,6 +967,34 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> { unsafe { llvm::LLVMBuildTrunc(self.llbuilder, val, dest_ty, UNNAMED) } } + fn unchecked_utrunc(&mut self, val: &'ll Value, dest_ty: &'ll Type) -> &'ll Value { + debug_assert_ne!(self.val_ty(val), dest_ty); + + let trunc = self.trunc(val, dest_ty); + if llvm_util::get_version() >= (19, 0, 0) { + unsafe { + if llvm::LLVMIsAInstruction(trunc).is_some() { + llvm::LLVMSetNUW(trunc, True); + } + } + } + trunc + } + + fn unchecked_strunc(&mut self, val: &'ll Value, dest_ty: &'ll Type) -> &'ll Value { + debug_assert_ne!(self.val_ty(val), dest_ty); + + let trunc = self.trunc(val, dest_ty); + if llvm_util::get_version() >= (19, 0, 0) { + unsafe { + if llvm::LLVMIsAInstruction(trunc).is_some() { + llvm::LLVMSetNSW(trunc, True); + } + } + } + trunc + } + fn sext(&mut self, val: &'ll Value, dest_ty: &'ll Type) -> &'ll Value { unsafe { llvm::LLVMBuildSExt(self.llbuilder, val, dest_ty, UNNAMED) } } |