From: Craig Topper <craig.topper@intel.com>
Date: Fri, 7 Sep 2018 19:14:24 +0000 (+0000)
Subject: [X86] Custom emit __builtin_rdtscp so we can emit an explicit store for the out parameter
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=923d959b1770881908b60041bbf544ade3d88c35;p=clang

[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

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@341699 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CGBuiltin.cpp b/lib/CodeGen/CGBuiltin.cpp
index a472bf59d7..90505ac088 100644
--- a/lib/CodeGen/CGBuiltin.cpp
+++ b/lib/CodeGen/CGBuiltin.cpp
@@ -9158,6 +9158,12 @@ Value *CodeGenFunction::EmitX86BuiltinExpr(unsigned BuiltinID,
   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:
diff --git a/test/CodeGen/rd-builtins.c b/test/CodeGen/rd-builtins.c
index 0d7cd04d6f..38e0886f03 100644
--- a/test/CodeGen/rd-builtins.c
+++ b/test/CodeGen/rd-builtins.c
@@ -14,3 +14,12 @@ int test_rdtsc() {
 // CHECK: @test_rdtsc
 // CHECK: call i64 @llvm.x86.rdtsc
 }
+
+unsigned long long test_rdtscp(unsigned int *a) {
+// CHECK: @test_rdtscp
+// CHECK: [[RDTSCP:%.*]] = call { i64, i32 } @llvm.x86.rdtscp
+// CHECK: [[TSC_AUX:%.*]] = extractvalue { i64, i32 } [[RDTSCP]], 1
+// CHECK: store i32 [[TSC_AUX]], i32* %{{.*}}
+// CHECK: [[TSC:%.*]] = extractvalue { i64, i32 } [[RDTSCP]], 0
+  return __rdtscp(a);
+}