[X86] Custom emit __builtin_rdtscp so we can emit an explicit store for the out parameter
This is the clang side of D51803. The llvm intrinsic now returns two results. So we need to emit an explicit store in IR for the out parameter. This is similar to addcarry/subborrow/rdrand/rdseed.
Differential Revision: https://reviews.llvm.org/D51805
llvm-svn: 341699
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index a472bf5..90505ac 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -9158,6 +9158,12 @@
case X86::BI__rdtsc: {
return Builder.CreateCall(CGM.getIntrinsic(Intrinsic::x86_rdtsc));
}
+ case X86::BI__builtin_ia32_rdtscp: {
+ Value *Call = Builder.CreateCall(CGM.getIntrinsic(Intrinsic::x86_rdtscp));
+ Builder.CreateDefaultAlignedStore(Builder.CreateExtractValue(Call, 1),
+ Ops[0]);
+ return Builder.CreateExtractValue(Call, 0);
+ }
case X86::BI__builtin_ia32_undef128:
case X86::BI__builtin_ia32_undef256:
case X86::BI__builtin_ia32_undef512: