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Use LLVM C-API to build atomic cmpxchg and fence

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This commit is contained in:
Josh Stone 2022-09-18 15:49:49 -07:00
parent a37499ae66
commit fac12e25dd
3 changed files with 25 additions and 76 deletions
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26
compiler/rustc_codegen_llvm/src/builder.rs
View file

@ -1,14 +1,13 @@
use crate::attributes;
use crate::common::Funclet;
use crate::context::CodegenCx;
use crate::llvm::{self, BasicBlock, False};
use crate::llvm::{AtomicOrdering, AtomicRmwBinOp, SynchronizationScope};
use crate::llvm::{self, AtomicOrdering, AtomicRmwBinOp, BasicBlock};
use crate::type_::Type;
use crate::type_of::LayoutLlvmExt;
use crate::value::Value;
use cstr::cstr;
use libc::{c_char, c_uint};
use rustc_codegen_ssa::common::{IntPredicate, RealPredicate, TypeKind};
use rustc_codegen_ssa::common::{IntPredicate, RealPredicate, SynchronizationScope, TypeKind};
use rustc_codegen_ssa::mir::operand::{OperandRef, OperandValue};
use rustc_codegen_ssa::mir::place::PlaceRef;
use rustc_codegen_ssa::traits::*;
@ -1042,15 +1041,17 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
) -> &'ll Value {
let weak = if weak { llvm::True } else { llvm::False };
unsafe {
llvm::LLVMRustBuildAtomicCmpXchg(
let value = llvm::LLVMBuildAtomicCmpXchg(
self.llbuilder,
dst,
cmp,
src,
AtomicOrdering::from_generic(order),
AtomicOrdering::from_generic(failure_order),
weak,
)
llvm::False, // SingleThreaded
);
llvm::LLVMSetWeak(value, weak);
value
}
}
fn atomic_rmw(
@ -1067,7 +1068,7 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
dst,
src,
AtomicOrdering::from_generic(order),
False,
llvm::False, // SingleThreaded
)
}
}
@ -1075,13 +1076,18 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
fn atomic_fence(
&mut self,
order: rustc_codegen_ssa::common::AtomicOrdering,
scope: rustc_codegen_ssa::common::SynchronizationScope,
scope: SynchronizationScope,
) {
let single_threaded = match scope {
SynchronizationScope::SingleThread => llvm::True,
SynchronizationScope::CrossThread => llvm::False,
};
unsafe {
llvm::LLVMRustBuildAtomicFence(
llvm::LLVMBuildFence(
self.llbuilder,
AtomicOrdering::from_generic(order),
SynchronizationScope::from_generic(scope),
single_threaded,
UNNAMED,
);
}
}

36
compiler/rustc_codegen_llvm/src/llvm/ffi.rs
View file

@ -400,27 +400,6 @@ impl AtomicOrdering {
}
}
/// LLVMRustSynchronizationScope
#[derive(Copy, Clone)]
#[repr(C)]
pub enum SynchronizationScope {
SingleThread,
CrossThread,
}
impl SynchronizationScope {
pub fn from_generic(sc: rustc_codegen_ssa::common::SynchronizationScope) -> Self {
match sc {
rustc_codegen_ssa::common::SynchronizationScope::SingleThread => {
SynchronizationScope::SingleThread
}
rustc_codegen_ssa::common::SynchronizationScope::CrossThread => {
SynchronizationScope::CrossThread
}
}
}
}
/// LLVMRustFileType
#[derive(Copy, Clone)]
#[repr(C)]
@ -1782,16 +1761,18 @@ extern "C" {
Order: AtomicOrdering,
) -> &'a Value;
pub fn LLVMRustBuildAtomicCmpXchg<'a>(
pub fn LLVMBuildAtomicCmpXchg<'a>(
B: &Builder<'a>,
LHS: &'a Value,
CMP: &'a Value,
RHS: &'a Value,
Order: AtomicOrdering,
FailureOrder: AtomicOrdering,
Weak: Bool,
SingleThreaded: Bool,
) -> &'a Value;
pub fn LLVMSetWeak(CmpXchgInst: &Value, IsWeak: Bool);
pub fn LLVMBuildAtomicRMW<'a>(
B: &Builder<'a>,
Op: AtomicRmwBinOp,
@ -1801,11 +1782,12 @@ extern "C" {
SingleThreaded: Bool,
) -> &'a Value;
pub fn LLVMRustBuildAtomicFence(
B: &Builder<'_>,
pub fn LLVMBuildFence<'a>(
B: &Builder<'a>,
Order: AtomicOrdering,
Scope: SynchronizationScope,
);
SingleThreaded: Bool,
Name: *const c_char,
) -> &'a Value;
/// Writes a module to the specified path. Returns 0 on success.
pub fn LLVMWriteBitcodeToFile(M: &Module, Path: *const c_char) -> c_int;