Expose IRBuilder::CreateAtomicCmpXchg as LLVMBuildAtomicCmpXchg in the C API.

[bnieuwenhuizen]

Summary

Also expose getters and setters in the C API, so that the change can be tested.

[bnieuwenhuizen]

Fixed a stray tab.

[mehdi_amini]

include/llvm-c/Core.h

2949

Returning a bool, I'd prefix it isXXX instead of getXXX

lib/IR/Core.cpp

2941

I'd name it so that it is explicit that it only operates on cmpxchg.
Something like: LLVMGetCmpXchgSuccessOrdering(LLVMValueRef CmpXchgInst)
(same in the other API)

[bnieuwenhuizen]

Did suggested name changes.

[mehdi_amini]

LGTM

[bnieuwenhuizen]

I would be grateful if you could commit this change.

[mehdi_amini]

r263886

include/llvm-c/Core.h

 LLVMValueRef LLVMBuildPtrDiff(LLVMBuilderRef, LLVMValueRef LHS,
                               LLVMValueRef RHS, const char *Name);
 LLVMValueRef LLVMBuildFence(LLVMBuilderRef B, LLVMAtomicOrdering ordering,
                             LLVMBool singleThread, const char *Name);
 LLVMValueRef LLVMBuildAtomicRMW(LLVMBuilderRef B, LLVMAtomicRMWBinOp op,
                                 LLVMValueRef PTR, LLVMValueRef Val,
                                 LLVMAtomicOrdering ordering,
                                 LLVMBool singleThread);
+LLVMValueRef LLVMBuildAtomicCmpXchg(LLVMBuilderRef B, LLVMValueRef Ptr,
+                                    LLVMValueRef Cmp, LLVMValueRef New,
+                                    LLVMAtomicOrdering SuccessOrdering,
+                                    LLVMAtomicOrdering FailureOrdering,
+                                    LLVMBool SingleThread);
+
+LLVMBool LLVMGetSingleThread(LLVMValueRef MemoryAccessInst);
+void LLVMSetSingleThread(LLVMValueRef MemoryAccessInst, LLVMBool SingleThread);
+
+LLVMAtomicOrdering LLVMGetSuccessOrdering(LLVMValueRef MemoryAccessInst);
+void LLVMSetSuccessOrdering(LLVMValueRef MemoryAccessInst,
+                            LLVMAtomicOrdering Ordering);
+LLVMAtomicOrdering LLVMGetFailureOrdering(LLVMValueRef MemoryAccessInst);
+void LLVMSetFailureOrdering(LLVMValueRef MemoryAccessInst,
+                            LLVMAtomicOrdering Ordering);
 
 /**
  * @}
  */
 
 /**
  * @defgroup LLVMCCoreModuleProvider Module Providers
  *

lib/IR/Core.cpp

switch (op) {
     case LLVMAtomicRMWBinOpMin: intop = AtomicRMWInst::Min; break;
     case LLVMAtomicRMWBinOpUMax: intop = AtomicRMWInst::UMax; break;
     case LLVMAtomicRMWBinOpUMin: intop = AtomicRMWInst::UMin; break;
   }
   return wrap(unwrap(B)->CreateAtomicRMW(intop, unwrap(PTR), unwrap(Val),
     mapFromLLVMOrdering(ordering), singleThread ? SingleThread : CrossThread));
 }
 
+LLVMValueRef LLVMBuildAtomicCmpXchg(LLVMBuilderRef B, LLVMValueRef Ptr,
+                                    LLVMValueRef Cmp, LLVMValueRef New,
+                                    LLVMAtomicOrdering SuccessOrdering,
+                                    LLVMAtomicOrdering FailureOrdering,
+                                    LLVMBool singleThread) {
+
+  return wrap(unwrap(B)->CreateAtomicCmpXchg(unwrap(Ptr), unwrap(Cmp),
+                unwrap(New), mapFromLLVMOrdering(SuccessOrdering),
+                mapFromLLVMOrdering(FailureOrdering),
+                singleThread ? SingleThread : CrossThread));
+}
+
+
+LLVMBool LLVMGetSingleThread(LLVMValueRef MemoryAccessInst) {
+  Value *P = unwrap<Value>(MemoryAccessInst);
+
+  if (AtomicRMWInst *I = dyn_cast<AtomicRMWInst>(P))
+    return I->getSynchScope() == SingleThread;
+  return cast<AtomicCmpXchgInst>(P)->getSynchScope() == SingleThread;
+}
+
+void LLVMSetSingleThread(LLVMValueRef MemoryAccessInst, LLVMBool NewValue) {
+  Value *P = unwrap<Value>(MemoryAccessInst);
+  SynchronizationScope Sync = NewValue ? SingleThread : CrossThread;
+
+  if (AtomicRMWInst *I = dyn_cast<AtomicRMWInst>(P))
+    return I->setSynchScope(Sync);
+  return cast<AtomicCmpXchgInst>(P)->setSynchScope(Sync);
+}
+
+LLVMAtomicOrdering LLVMGetSuccessOrdering(LLVMValueRef MemoryAccessInst)  {
+  Value *P = unwrap<Value>(MemoryAccessInst);
+  return mapToLLVMOrdering(cast<AtomicCmpXchgInst>(P)->getSuccessOrdering());
+}
+
+void LLVMSetSuccessOrdering(LLVMValueRef MemoryAccessInst,
+                            LLVMAtomicOrdering Ordering) {
+  Value *P = unwrap<Value>(MemoryAccessInst);
+  AtomicOrdering O = mapFromLLVMOrdering(Ordering);
+
+  return cast<AtomicCmpXchgInst>(P)->setSuccessOrdering(O);
+}
+
+LLVMAtomicOrdering LLVMGetFailureOrdering(LLVMValueRef MemoryAccessInst)  {
+  Value *P = unwrap<Value>(MemoryAccessInst);
+  return mapToLLVMOrdering(cast<AtomicCmpXchgInst>(P)->getFailureOrdering());
+}
+
+void LLVMSetFailureOrdering(LLVMValueRef MemoryAccessInst,
+                            LLVMAtomicOrdering Ordering) {
+  Value *P = unwrap<Value>(MemoryAccessInst);
+  AtomicOrdering O = mapFromLLVMOrdering(Ordering);
+
+  return cast<AtomicCmpXchgInst>(P)->setFailureOrdering(O);
+}
 
 /*===-- Module providers --------------------------------------------------===*/
 
 LLVMModuleProviderRef
 LLVMCreateModuleProviderForExistingModule(LLVMModuleRef M) {
   return reinterpret_cast<LLVMModuleProviderRef>(M);
 }
 

test/Bindings/llvm-c/atomics.ll

+; RUN: llvm-as < %s | llvm-dis > %t.orig
+; RUN: llvm-as < %s | llvm-c-test --echo > %t.echo
+; RUN: diff -w %t.orig %t.echo
+
+define i32 @main() {
+  %1 = alloca i32
+  %2 = cmpxchg i32* %1, i32 2, i32 3 seq_cst acquire
+  %3 = extractvalue { i32, i1 } %2, 0
+  ret i32 %3
+}

tools/llvm-c-test/echo.cpp

switch(Op) {
         for (int i = 1; i <= NumIdx; i++)
           Idx.push_back(CloneValue(LLVMGetOperand(Src, i)));
         if (LLVMIsInBounds(Src))
           Dst = LLVMBuildInBoundsGEP(Builder, Ptr, Idx.data(), NumIdx, Name);
         else
           Dst = LLVMBuildGEP(Builder, Ptr, Idx.data(), NumIdx, Name);
         break;
       }
+      case LLVMAtomicCmpXchg: {
+        LLVMValueRef Ptr = CloneValue(LLVMGetOperand(Src, 0));
+        LLVMValueRef Cmp = CloneValue(LLVMGetOperand(Src, 1));
+        LLVMValueRef New = CloneValue(LLVMGetOperand(Src, 2));
+        LLVMAtomicOrdering Succ = LLVMGetSuccessOrdering(Src);
+        LLVMAtomicOrdering Fail = LLVMGetFailureOrdering(Src);
+  LLVMBool SingleThread = LLVMGetSingleThread(Src);
+
+        Dst = LLVMBuildAtomicCmpXchg(Builder, Ptr, Cmp, New, Succ, Fail,
+                                     SingleThread);
+      } break;
       case LLVMBitCast: {
         LLVMValueRef V = CloneValue(LLVMGetOperand(Src, 0));
         Dst = LLVMBuildBitCast(Builder, V, CloneType(Src), Name);
         break;
       }
       case LLVMICmp: {
         LLVMIntPredicate Pred = LLVMGetICmpPredicate(Src);
         LLVMValueRef LHS = CloneValue(LLVMGetOperand(Src, 0));