[Clang] Re-write codegen for atomic_test_and_set and atomic_clear #120449
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Re-write the sema and codegen for the atomic_test_and_set and atomic_clear builtin functions to go via AtomicExpr, like the other atomic builtins do. This simplifies the code, because AtomicExpr already handles things like generating code for to dynamically select the memory ordering, which was duplicated for these builtins. This also fixes a few crash bugs, one when passing an integer to the pointer argument, and one when using an array. Fixes llvm#111293.
These memory orderings are not valid for the atomic_clear builtin according to https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html, so we should diagnose them.
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@llvm/pr-subscribers-clang @llvm/pr-subscribers-clang-codegen Author: Oliver Stannard (ostannard) ChangesRe-write the sema and codegen for the atomic_test_and_set and atomic_clear builtin functions to go via AtomicExpr, like the other atomic builtins do. This simplifies the code, because AtomicExpr already handles things like generating code for to dynamically select the memory ordering, which was duplicated for these builtins. This also fixes a few crash bugs, one when passing an integer to the pointer argument, and one when using an array. This also adds diagnostics for the memory orderings which are not valid for atomic_clear according to https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html, which were missing before. Fixes #111293. Patch is 26.62 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/120449.diff 7 Files Affected:
diff --git a/clang/include/clang/Basic/Builtins.td b/clang/include/clang/Basic/Builtins.td
index d64a66fc9d9cf7..b11e23bb2d6ad3 100644
--- a/clang/include/clang/Basic/Builtins.td
+++ b/clang/include/clang/Basic/Builtins.td
@@ -1977,15 +1977,15 @@ def AtomicNandFetch : AtomicBuiltin {
let Prototype = "void(...)";
}
-def AtomicTestAndSet : Builtin {
+def AtomicTestAndSet : AtomicBuiltin {
let Spellings = ["__atomic_test_and_set"];
- let Attributes = [NoThrow];
+ let Attributes = [NoThrow, CustomTypeChecking];
let Prototype = "bool(void volatile*, int)";
}
-def AtomicClear : Builtin {
+def AtomicClear : AtomicBuiltin {
let Spellings = ["__atomic_clear"];
- let Attributes = [NoThrow];
+ let Attributes = [NoThrow, CustomTypeChecking];
let Prototype = "void(void volatile*, int)";
}
diff --git a/clang/lib/AST/Expr.cpp b/clang/lib/AST/Expr.cpp
index 8c8ccdb61dc01c..7e6cb53064ff2b 100644
--- a/clang/lib/AST/Expr.cpp
+++ b/clang/lib/AST/Expr.cpp
@@ -5070,6 +5070,8 @@ unsigned AtomicExpr::getNumSubExprs(AtomicOp Op) {
case AO__opencl_atomic_init:
case AO__c11_atomic_load:
case AO__atomic_load_n:
+ case AO__atomic_test_and_set:
+ case AO__atomic_clear:
return 2;
case AO__scoped_atomic_load_n:
diff --git a/clang/lib/CodeGen/CGAtomic.cpp b/clang/lib/CodeGen/CGAtomic.cpp
index f6cb2ad421e906..3adb2a7ad207f0 100644
--- a/clang/lib/CodeGen/CGAtomic.cpp
+++ b/clang/lib/CodeGen/CGAtomic.cpp
@@ -723,6 +723,24 @@ static void EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *E, Address Dest,
case AtomicExpr::AO__scoped_atomic_fetch_nand:
Op = llvm::AtomicRMWInst::Nand;
break;
+
+ case AtomicExpr::AO__atomic_test_and_set: {
+ llvm::AtomicRMWInst *RMWI =
+ CGF.emitAtomicRMWInst(llvm::AtomicRMWInst::Xchg, Ptr,
+ CGF.Builder.getInt8(1), Order, Scope, E);
+ RMWI->setVolatile(E->isVolatile());
+ llvm::Value *Result = CGF.Builder.CreateIsNotNull(RMWI, "tobool");
+ CGF.Builder.CreateStore(Result, Dest);
+ return;
+ }
+
+ case AtomicExpr::AO__atomic_clear: {
+ llvm::StoreInst *Store =
+ CGF.Builder.CreateStore(CGF.Builder.getInt8(0), Ptr);
+ Store->setAtomic(Order, Scope);
+ Store->setVolatile(E->isVolatile());
+ return;
+ }
}
llvm::Value *LoadVal1 = CGF.Builder.CreateLoad(Val1);
@@ -878,6 +896,8 @@ RValue CodeGenFunction::EmitAtomicExpr(AtomicExpr *E) {
case AtomicExpr::AO__c11_atomic_load:
case AtomicExpr::AO__opencl_atomic_load:
case AtomicExpr::AO__hip_atomic_load:
+ case AtomicExpr::AO__atomic_test_and_set:
+ case AtomicExpr::AO__atomic_clear:
break;
case AtomicExpr::AO__atomic_load:
@@ -1200,6 +1220,8 @@ RValue CodeGenFunction::EmitAtomicExpr(AtomicExpr *E) {
case AtomicExpr::AO__opencl_atomic_fetch_max:
case AtomicExpr::AO__scoped_atomic_fetch_max:
case AtomicExpr::AO__scoped_atomic_max_fetch:
+ case AtomicExpr::AO__atomic_test_and_set:
+ case AtomicExpr::AO__atomic_clear:
llvm_unreachable("Integral atomic operations always become atomicrmw!");
}
@@ -1239,7 +1261,8 @@ RValue CodeGenFunction::EmitAtomicExpr(AtomicExpr *E) {
E->getOp() == AtomicExpr::AO__atomic_store ||
E->getOp() == AtomicExpr::AO__atomic_store_n ||
E->getOp() == AtomicExpr::AO__scoped_atomic_store ||
- E->getOp() == AtomicExpr::AO__scoped_atomic_store_n;
+ E->getOp() == AtomicExpr::AO__scoped_atomic_store_n ||
+ E->getOp() == AtomicExpr::AO__atomic_clear;
bool IsLoad = E->getOp() == AtomicExpr::AO__c11_atomic_load ||
E->getOp() == AtomicExpr::AO__opencl_atomic_load ||
E->getOp() == AtomicExpr::AO__hip_atomic_load ||
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 4d4b7428abd505..0ea2ee4c264aef 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -5099,147 +5099,6 @@ RValue CodeGenFunction::EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
ReturnValueSlot(), Args);
}
- case Builtin::BI__atomic_test_and_set: {
- // Look at the argument type to determine whether this is a volatile
- // operation. The parameter type is always volatile.
- QualType PtrTy = E->getArg(0)->IgnoreImpCasts()->getType();
- bool Volatile =
- PtrTy->castAs<PointerType>()->getPointeeType().isVolatileQualified();
-
- Address Ptr =
- EmitPointerWithAlignment(E->getArg(0)).withElementType(Int8Ty);
-
- Value *NewVal = Builder.getInt8(1);
- Value *Order = EmitScalarExpr(E->getArg(1));
- if (isa<llvm::ConstantInt>(Order)) {
- int ord = cast<llvm::ConstantInt>(Order)->getZExtValue();
- AtomicRMWInst *Result = nullptr;
- switch (ord) {
- case 0: // memory_order_relaxed
- default: // invalid order
- Result = Builder.CreateAtomicRMW(llvm::AtomicRMWInst::Xchg, Ptr, NewVal,
- llvm::AtomicOrdering::Monotonic);
- break;
- case 1: // memory_order_consume
- case 2: // memory_order_acquire
- Result = Builder.CreateAtomicRMW(llvm::AtomicRMWInst::Xchg, Ptr, NewVal,
- llvm::AtomicOrdering::Acquire);
- break;
- case 3: // memory_order_release
- Result = Builder.CreateAtomicRMW(llvm::AtomicRMWInst::Xchg, Ptr, NewVal,
- llvm::AtomicOrdering::Release);
- break;
- case 4: // memory_order_acq_rel
-
- Result = Builder.CreateAtomicRMW(llvm::AtomicRMWInst::Xchg, Ptr, NewVal,
- llvm::AtomicOrdering::AcquireRelease);
- break;
- case 5: // memory_order_seq_cst
- Result = Builder.CreateAtomicRMW(
- llvm::AtomicRMWInst::Xchg, Ptr, NewVal,
- llvm::AtomicOrdering::SequentiallyConsistent);
- break;
- }
- Result->setVolatile(Volatile);
- return RValue::get(Builder.CreateIsNotNull(Result, "tobool"));
- }
-
- llvm::BasicBlock *ContBB = createBasicBlock("atomic.continue", CurFn);
-
- llvm::BasicBlock *BBs[5] = {
- createBasicBlock("monotonic", CurFn),
- createBasicBlock("acquire", CurFn),
- createBasicBlock("release", CurFn),
- createBasicBlock("acqrel", CurFn),
- createBasicBlock("seqcst", CurFn)
- };
- llvm::AtomicOrdering Orders[5] = {
- llvm::AtomicOrdering::Monotonic, llvm::AtomicOrdering::Acquire,
- llvm::AtomicOrdering::Release, llvm::AtomicOrdering::AcquireRelease,
- llvm::AtomicOrdering::SequentiallyConsistent};
-
- Order = Builder.CreateIntCast(Order, Builder.getInt32Ty(), false);
- llvm::SwitchInst *SI = Builder.CreateSwitch(Order, BBs[0]);
-
- Builder.SetInsertPoint(ContBB);
- PHINode *Result = Builder.CreatePHI(Int8Ty, 5, "was_set");
-
- for (unsigned i = 0; i < 5; ++i) {
- Builder.SetInsertPoint(BBs[i]);
- AtomicRMWInst *RMW = Builder.CreateAtomicRMW(llvm::AtomicRMWInst::Xchg,
- Ptr, NewVal, Orders[i]);
- RMW->setVolatile(Volatile);
- Result->addIncoming(RMW, BBs[i]);
- Builder.CreateBr(ContBB);
- }
-
- SI->addCase(Builder.getInt32(0), BBs[0]);
- SI->addCase(Builder.getInt32(1), BBs[1]);
- SI->addCase(Builder.getInt32(2), BBs[1]);
- SI->addCase(Builder.getInt32(3), BBs[2]);
- SI->addCase(Builder.getInt32(4), BBs[3]);
- SI->addCase(Builder.getInt32(5), BBs[4]);
-
- Builder.SetInsertPoint(ContBB);
- return RValue::get(Builder.CreateIsNotNull(Result, "tobool"));
- }
-
- case Builtin::BI__atomic_clear: {
- QualType PtrTy = E->getArg(0)->IgnoreImpCasts()->getType();
- bool Volatile =
- PtrTy->castAs<PointerType>()->getPointeeType().isVolatileQualified();
-
- Address Ptr = EmitPointerWithAlignment(E->getArg(0));
- Ptr = Ptr.withElementType(Int8Ty);
- Value *NewVal = Builder.getInt8(0);
- Value *Order = EmitScalarExpr(E->getArg(1));
- if (isa<llvm::ConstantInt>(Order)) {
- int ord = cast<llvm::ConstantInt>(Order)->getZExtValue();
- StoreInst *Store = Builder.CreateStore(NewVal, Ptr, Volatile);
- switch (ord) {
- case 0: // memory_order_relaxed
- default: // invalid order
- Store->setOrdering(llvm::AtomicOrdering::Monotonic);
- break;
- case 3: // memory_order_release
- Store->setOrdering(llvm::AtomicOrdering::Release);
- break;
- case 5: // memory_order_seq_cst
- Store->setOrdering(llvm::AtomicOrdering::SequentiallyConsistent);
- break;
- }
- return RValue::get(nullptr);
- }
-
- llvm::BasicBlock *ContBB = createBasicBlock("atomic.continue", CurFn);
-
- llvm::BasicBlock *BBs[3] = {
- createBasicBlock("monotonic", CurFn),
- createBasicBlock("release", CurFn),
- createBasicBlock("seqcst", CurFn)
- };
- llvm::AtomicOrdering Orders[3] = {
- llvm::AtomicOrdering::Monotonic, llvm::AtomicOrdering::Release,
- llvm::AtomicOrdering::SequentiallyConsistent};
-
- Order = Builder.CreateIntCast(Order, Builder.getInt32Ty(), false);
- llvm::SwitchInst *SI = Builder.CreateSwitch(Order, BBs[0]);
-
- for (unsigned i = 0; i < 3; ++i) {
- Builder.SetInsertPoint(BBs[i]);
- StoreInst *Store = Builder.CreateStore(NewVal, Ptr, Volatile);
- Store->setOrdering(Orders[i]);
- Builder.CreateBr(ContBB);
- }
-
- SI->addCase(Builder.getInt32(0), BBs[0]);
- SI->addCase(Builder.getInt32(3), BBs[1]);
- SI->addCase(Builder.getInt32(5), BBs[2]);
-
- Builder.SetInsertPoint(ContBB);
- return RValue::get(nullptr);
- }
-
case Builtin::BI__atomic_thread_fence:
case Builtin::BI__atomic_signal_fence:
case Builtin::BI__c11_atomic_thread_fence:
diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index a248a6b53b0d06..8597b346b297c1 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -3631,6 +3631,7 @@ static bool isValidOrderingForOp(int64_t Ordering, AtomicExpr::AtomicOp Op) {
case AtomicExpr::AO__atomic_store_n:
case AtomicExpr::AO__scoped_atomic_store:
case AtomicExpr::AO__scoped_atomic_store_n:
+ case AtomicExpr::AO__atomic_clear:
return OrderingCABI != llvm::AtomicOrderingCABI::consume &&
OrderingCABI != llvm::AtomicOrderingCABI::acquire &&
OrderingCABI != llvm::AtomicOrderingCABI::acq_rel;
@@ -3683,12 +3684,18 @@ ExprResult Sema::BuildAtomicExpr(SourceRange CallRange, SourceRange ExprRange,
C11CmpXchg,
// bool __atomic_compare_exchange(A *, C *, CP, bool, int, int)
- GNUCmpXchg
+ GNUCmpXchg,
+
+ // bool __atomic_test_and_set(A *, int)
+ TestAndSet,
+
+ // void __atomic_clear(A *, int)
+ Clear,
} Form = Init;
- const unsigned NumForm = GNUCmpXchg + 1;
- const unsigned NumArgs[] = { 2, 2, 3, 3, 3, 3, 4, 5, 6 };
- const unsigned NumVals[] = { 1, 0, 1, 1, 1, 1, 2, 2, 3 };
+ const unsigned NumForm = Clear + 1;
+ const unsigned NumArgs[] = { 2, 2, 3, 3, 3, 3, 4, 5, 6, 2, 2 };
+ const unsigned NumVals[] = { 1, 0, 1, 1, 1, 1, 2, 2, 3, 0, 0 };
// where:
// C is an appropriate type,
// A is volatile _Atomic(C) for __c11 builtins and is C for GNU builtins,
@@ -3849,6 +3856,14 @@ ExprResult Sema::BuildAtomicExpr(SourceRange CallRange, SourceRange ExprRange,
case AtomicExpr::AO__scoped_atomic_compare_exchange_n:
Form = GNUCmpXchg;
break;
+
+ case AtomicExpr::AO__atomic_test_and_set:
+ Form = TestAndSet;
+ break;
+
+ case AtomicExpr::AO__atomic_clear:
+ Form = Clear;
+ break;
}
unsigned AdjustedNumArgs = NumArgs[Form];
@@ -3995,9 +4010,9 @@ ExprResult Sema::BuildAtomicExpr(SourceRange CallRange, SourceRange ExprRange,
ValType.removeLocalConst();
QualType ResultType = ValType;
if (Form == Copy || Form == LoadCopy || Form == GNUXchg ||
- Form == Init)
+ Form == Init || Form == Clear)
ResultType = Context.VoidTy;
- else if (Form == C11CmpXchg || Form == GNUCmpXchg)
+ else if (Form == C11CmpXchg || Form == GNUCmpXchg || Form == TestAndSet)
ResultType = Context.BoolTy;
// The type of a parameter passed 'by value'. In the GNU atomics, such
@@ -4042,6 +4057,10 @@ ExprResult Sema::BuildAtomicExpr(SourceRange CallRange, SourceRange ExprRange,
APIOrderedArgs.push_back(Args[1]); // Order
APIOrderedArgs.push_back(Args[3]); // OrderFail
break;
+ case TestAndSet:
+ case Clear:
+ APIOrderedArgs.push_back(Args[1]); // Order
+ break;
}
} else
APIOrderedArgs.append(Args.begin(), Args.end());
@@ -4127,6 +4146,8 @@ ExprResult Sema::BuildAtomicExpr(SourceRange CallRange, SourceRange ExprRange,
SubExprs.push_back(APIOrderedArgs[1]); // Val1
break;
case Load:
+ case TestAndSet:
+ case Clear:
SubExprs.push_back(APIOrderedArgs[1]); // Order
break;
case LoadCopy:
diff --git a/clang/test/CodeGen/atomic-test-and-set.c b/clang/test/CodeGen/atomic-test-and-set.c
new file mode 100644
index 00000000000000..bb05623f897551
--- /dev/null
+++ b/clang/test/CodeGen/atomic-test-and-set.c
@@ -0,0 +1,250 @@
+// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 5
+// RUN: %clang_cc1 %s -emit-llvm -o - -triple=aarch64-none-elf | FileCheck %s
+// REQUIRES: aarch64-registered-target
+
+#include <stdatomic.h>
+
+// CHECK-LABEL: define dso_local void @clear_relaxed(
+// CHECK-SAME: ptr noundef [[PTR:%.*]]) #[[ATTR0:[0-9]+]] {
+// CHECK-NEXT: [[ENTRY:.*:]]
+// CHECK-NEXT: [[PTR_ADDR:%.*]] = alloca ptr, align 8
+// CHECK-NEXT: store ptr [[PTR]], ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: store atomic i8 0, ptr [[TMP0]] monotonic, align 1
+// CHECK-NEXT: ret void
+//
+void clear_relaxed(char *ptr) {
+ __atomic_clear(ptr, memory_order_relaxed);
+}
+
+// CHECK-LABEL: define dso_local void @clear_seq_cst(
+// CHECK-SAME: ptr noundef [[PTR:%.*]]) #[[ATTR0]] {
+// CHECK-NEXT: [[ENTRY:.*:]]
+// CHECK-NEXT: [[PTR_ADDR:%.*]] = alloca ptr, align 8
+// CHECK-NEXT: store ptr [[PTR]], ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: store atomic i8 0, ptr [[TMP0]] seq_cst, align 1
+// CHECK-NEXT: ret void
+//
+void clear_seq_cst(char *ptr) {
+ __atomic_clear(ptr, memory_order_seq_cst);
+}
+
+// CHECK-LABEL: define dso_local void @clear_release(
+// CHECK-SAME: ptr noundef [[PTR:%.*]]) #[[ATTR0]] {
+// CHECK-NEXT: [[ENTRY:.*:]]
+// CHECK-NEXT: [[PTR_ADDR:%.*]] = alloca ptr, align 8
+// CHECK-NEXT: store ptr [[PTR]], ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: store atomic i8 0, ptr [[TMP0]] release, align 1
+// CHECK-NEXT: ret void
+//
+void clear_release(char *ptr) {
+ __atomic_clear(ptr, memory_order_release);
+}
+
+// CHECK-LABEL: define dso_local void @clear_dynamic(
+// CHECK-SAME: ptr noundef [[PTR:%.*]], i32 noundef [[ORDER:%.*]]) #[[ATTR0]] {
+// CHECK-NEXT: [[ENTRY:.*:]]
+// CHECK-NEXT: [[PTR_ADDR:%.*]] = alloca ptr, align 8
+// CHECK-NEXT: [[ORDER_ADDR:%.*]] = alloca i32, align 4
+// CHECK-NEXT: store ptr [[PTR]], ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: store i32 [[ORDER]], ptr [[ORDER_ADDR]], align 4
+// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: [[TMP1:%.*]] = load i32, ptr [[ORDER_ADDR]], align 4
+// CHECK-NEXT: switch i32 [[TMP1]], label %[[MONOTONIC:.*]] [
+// CHECK-NEXT: i32 3, label %[[RELEASE:.*]]
+// CHECK-NEXT: i32 5, label %[[SEQCST:.*]]
+// CHECK-NEXT: ]
+// CHECK: [[MONOTONIC]]:
+// CHECK-NEXT: store atomic i8 0, ptr [[TMP0]] monotonic, align 1
+// CHECK-NEXT: br label %[[ATOMIC_CONTINUE:.*]]
+// CHECK: [[RELEASE]]:
+// CHECK-NEXT: store atomic i8 0, ptr [[TMP0]] release, align 1
+// CHECK-NEXT: br label %[[ATOMIC_CONTINUE]]
+// CHECK: [[SEQCST]]:
+// CHECK-NEXT: store atomic i8 0, ptr [[TMP0]] seq_cst, align 1
+// CHECK-NEXT: br label %[[ATOMIC_CONTINUE]]
+// CHECK: [[ATOMIC_CONTINUE]]:
+// CHECK-NEXT: ret void
+//
+void clear_dynamic(char *ptr, int order) {
+ __atomic_clear(ptr, order);
+}
+
+// CHECK-LABEL: define dso_local void @test_and_set_relaxed(
+// CHECK-SAME: ptr noundef [[PTR:%.*]]) #[[ATTR0]] {
+// CHECK-NEXT: [[ENTRY:.*:]]
+// CHECK-NEXT: [[PTR_ADDR:%.*]] = alloca ptr, align 8
+// CHECK-NEXT: [[ATOMIC_TEMP:%.*]] = alloca i8, align 1
+// CHECK-NEXT: store ptr [[PTR]], ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: [[TMP1:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 monotonic, align 1
+// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[TMP1]], 0
+// CHECK-NEXT: store i1 [[TOBOOL]], ptr [[ATOMIC_TEMP]], align 1
+// CHECK-NEXT: [[TMP2:%.*]] = load i8, ptr [[ATOMIC_TEMP]], align 1
+// CHECK-NEXT: [[LOADEDV:%.*]] = trunc i8 [[TMP2]] to i1
+// CHECK-NEXT: ret void
+//
+void test_and_set_relaxed(char *ptr) {
+ __atomic_test_and_set(ptr, memory_order_relaxed);
+}
+
+// CHECK-LABEL: define dso_local void @test_and_set_consume(
+// CHECK-SAME: ptr noundef [[PTR:%.*]]) #[[ATTR0]] {
+// CHECK-NEXT: [[ENTRY:.*:]]
+// CHECK-NEXT: [[PTR_ADDR:%.*]] = alloca ptr, align 8
+// CHECK-NEXT: [[ATOMIC_TEMP:%.*]] = alloca i8, align 1
+// CHECK-NEXT: store ptr [[PTR]], ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: [[TMP1:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 acquire, align 1
+// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[TMP1]], 0
+// CHECK-NEXT: store i1 [[TOBOOL]], ptr [[ATOMIC_TEMP]], align 1
+// CHECK-NEXT: [[TMP2:%.*]] = load i8, ptr [[ATOMIC_TEMP]], align 1
+// CHECK-NEXT: [[LOADEDV:%.*]] = trunc i8 [[TMP2]] to i1
+// CHECK-NEXT: ret void
+//
+void test_and_set_consume(char *ptr) {
+ __atomic_test_and_set(ptr, memory_order_consume);
+}
+
+// CHECK-LABEL: define dso_local void @test_and_set_acquire(
+// CHECK-SAME: ptr noundef [[PTR:%.*]]) #[[ATTR0]] {
+// CHECK-NEXT: [[ENTRY:.*:]]
+// CHECK-NEXT: [[PTR_ADDR:%.*]] = alloca ptr, align 8
+// CHECK-NEXT: [[ATOMIC_TEMP:%.*]] = alloca i8, align 1
+// CHECK-NEXT: store ptr [[PTR]], ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: [[TMP1:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 acquire, align 1
+// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[TMP1]], 0
+// CHECK-NEXT: store i1 [[TOBOOL]], ptr [[ATOMIC_TEMP]], align 1
+// CHECK-NEXT: [[TMP2:%.*]] = load i8, ptr [[ATOMIC_TEMP]], align 1
+// CHECK-NEXT: [[LOADEDV:%.*]] = trunc i8 [[TMP2]] to i1
+// CHECK-NEXT: ret void
+//
+void test_and_set_acquire(char *ptr) {
+ __atomic_test_and_set(ptr, memory_order_acquire);
+}
+
+// CHECK-LABEL: define dso_local void @test_and_set_release(
+// CHECK-SAME: ptr noundef [[PTR:%.*]]) #[[ATTR0]] {
+// CHECK-NEXT: [[ENTRY:.*:]]
+// CHECK-NEXT: [[PTR_ADDR:%.*]] = alloca ptr, align 8
+// CHECK-NEXT: [[ATOMIC_TEMP:%.*]] = alloca i8, align 1
+// CHECK-NEXT: store ptr [[PTR]], ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: [[TMP1:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 release, align 1
+// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[TMP1]], 0
+// CHECK-NEXT: store i1 [[TOBOOL]], ptr [[ATOMIC_TEMP]], align 1
+// CHECK-NEXT: [[TMP2:%.*]] = load i8, ptr [[ATOMIC_TEMP]], align 1
+// CHECK-NEXT: [[LOADEDV:%.*]] = trunc i8 [[TMP2]] to i1
+// CHECK-NEXT: ret void
+//
+void test_and_set_release(char *ptr) {
+ __atomic_test_and_set(ptr, memory_order_release);
+}
+
+// CHECK-LABEL: define dso_local void @test_and_set_acq_rel(
+// CHECK-SAME: ptr noundef [[PTR:%.*]]) #[[ATTR0]] {
+// CHECK-NEXT: [[ENTRY:.*:]]
+// CHECK-NEXT: [[PTR_ADDR:%.*]] = alloca ptr, align 8
+// CHECK-NEXT: [[ATOMIC_TEMP:%.*]] = alloca i8, align 1
+// CHECK-NEXT: store ptr [[PTR]], ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
+// CHECK-NEXT: [[TMP1:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 acq_rel, align 1
+// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[TMP1]], 0
+// CHECK-NEXT: store i1 [[TOBOOL]], ptr [[ATOMIC_TEMP]], align 1
+// C...
[truncated]
|
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✅ With the latest revision this PR passed the C/C++ code formatter. |
efriedma-quic
approved these changes
Dec 18, 2024
| let Spellings = ["__atomic_clear"]; | ||
| let Attributes = [NoThrow]; | ||
| let Attributes = [NoThrow, CustomTypeChecking]; |
There was a problem hiding this comment.
For builtins that use custom type checking, we usually use something like void(...) instead of void(void volatile*, int). But as far as I remember, we ignore the signature anyway, so it doesn't matter very much.
|
This appears to introduce a regression with respect to incomplete types: #include <stdbool.h>
void func1(bool x) { __atomic_test_and_set((void *)(&x), __ATOMIC_SEQ_CST); }
void func2(bool x) {__atomic_clear((void *)(&x), __ATOMIC_SEQ_CST); }Previously compiled w/ no errors/warnings, but now fails with: $ clang -c /tmp/atomic.c -o /dev/null
/tmp/atomic.c:2:44: error: incomplete type 'void' where a complete type is required
2 | void func1(bool x) { __atomic_test_and_set((void *)(&x), __ATOMIC_SEQ_CST); }
| ^
/tmp/atomic.c:3:36: error: incomplete type 'void' where a complete type is required
3 | void func2(bool x) {__atomic_clear((void *)(&x), __ATOMIC_SEQ_CST); }
| ^
2 errors generated.According to the doc linked in the PR description, https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html, |
#define _cap_mu_blocked(x) \
__atomic_test_and_set((void *)(x), __ATOMIC_SEQ_CST)
#define _cap_mu_lock(x) \
while (_cap_mu_blocked(x)) sched_yield()
#define _cap_mu_unlock(x) \
__atomic_clear((void *) (x), __ATOMIC_SEQ_CST)
#define _cap_mu_unlock_return(x, y) \
do { _cap_mu_unlock(x); return (y); } while (0) |
|
Yes, the code in libpcap is correct, and the new Clang behavior is incorrect.
|
metaflow
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Dec 20, 2024
…lear (#120449)" This reverts commit 9fc2fad. See #120449 (comment)
|
Thanks for the revert, I'm on holiday now so I'll have another go at fixing this in the new year. |
|
@ostannard 🎄 🎅 happy holidays |
ostannard
added a commit
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that referenced
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Jan 7, 2025
…vm#120449) Re-write the sema and codegen for the atomic_test_and_set and atomic_clear builtin functions to go via AtomicExpr, like the other atomic builtins do. This simplifies the code, because AtomicExpr already handles things like generating code for to dynamically select the memory ordering, which was duplicated for these builtins. This also fixes a few crash bugs, one when passing an integer to the pointer argument, and one when using an array. This also adds diagnostics for the memory orderings which are not valid for atomic_clear according to https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html, which were missing before. Fixes llvm#111293.
|
Updated version: #121943 |
github-actions bot
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Jan 10, 2025
…nd atomic_clear (#120449)" This reverts commit 9fc2fad. See llvm/llvm-project#120449 (comment)
ostannard
added a commit
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Jan 22, 2025
…21943) Re-write the sema and codegen for the atomic_test_and_set and atomic_clear builtin functions to go via AtomicExpr, like the other atomic builtins do. This simplifies the code, because AtomicExpr already handles things like generating code for to dynamically select the memory ordering, which was duplicated for these builtins. This also fixes a few crash bugs, one when passing an integer to the pointer argument, and one when using an array. This also adds diagnostics for the memory orderings which are not valid for atomic_clear according to https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html, which were missing before. Fixes #111293. This is a re-land of #120449, modified to allow any non-const pointer type for the first argument.
qiaojbao
pushed a commit
to GPUOpen-Drivers/llvm-project
that referenced
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Feb 7, 2025
Local branch amd-gfx ab47d36 Merged main:e8a656376857 into amd-gfx:bc4e29b082d5 Remote branch main 93743ee Revert "[Clang] Re-write codegen for atomic_test_and_set and atomic_clear (llvm#120449)" Change-Id: I7a7d9611b41c601f1b7064b61ca1831b91819a96
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Re-write the sema and codegen for the atomic_test_and_set and atomic_clear builtin functions to go via AtomicExpr, like the other atomic builtins do. This simplifies the code, because AtomicExpr already handles things like generating code for to dynamically select the memory ordering, which was duplicated for these builtins. This also fixes a few crash bugs, one when passing an integer to the pointer argument, and one when using an array.
This also adds diagnostics for the memory orderings which are not valid for atomic_clear according to https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html, which were missing before.
Fixes #111293.