Implement CodeGen for __builtin_memcpy.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@51282 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/CGBuiltin.cpp b/lib/CodeGen/CGBuiltin.cpp
index d15780a63ba7205b4bc33c7f7bf64cca843fc87c..e29a1742293ce1c3d1ec9e16c127727134874091 100644 (file)
--- a/lib/CodeGen/CGBuiltin.cpp
+++ b/lib/CodeGen/CGBuiltin.cpp
@@ -252,6 +252,16 @@ RValue CodeGenFunction::EmitBuiltinExpr(unsigned BuiltinID, const CallExpr *E) {
     return RValue::get(Builder.CreateAlloca(llvm::Type::Int8Ty,
                                             EmitScalarExpr(E->getArg(0)),
                                             "tmp"));
+  case Builtin::BI__builtin_memcpy: {
+    Value* MemCpyOps[4] = {
+      EmitScalarExpr(E->getArg(0)),
+      EmitScalarExpr(E->getArg(1)),
+      EmitScalarExpr(E->getArg(2)),
+      llvm::ConstantInt::get(llvm::Type::Int32Ty, 0)
+    };
+    Builder.CreateCall(CGM.getMemCpyFn(), MemCpyOps, MemCpyOps+4);
+    return RValue::get(MemCpyOps[0]);
+  }
   case Builtin::BI__sync_fetch_and_add:
     return EmitBinaryAtomic(*this, Intrinsic::atomic_las, E);
   case Builtin::BI__sync_fetch_and_sub:

diff --git a/test/CodeGen/builtinmemcpy.c b/test/CodeGen/builtinmemcpy.c
new file mode 100644 (file)
index 0000000..8600d98
--- /dev/null
+++ b/test/CodeGen/builtinmemcpy.c
@@ -0,0 +1,3 @@
+// RUN: clang -emit-llvm < %s -o - | grep "llvm.memcpy"
+
+char* x(char* a, char* b) {return __builtin_memcpy(a, b, 4);}