3 files changed, 40 insertions, 0 deletions
diff --git a/clang/lib/Basic/Targets.cpp b/clang/lib/Basic/Targets.cpp
index 09e7dad0639..701c0a9e707 100644
--- a/clang/lib/Basic/Targets.cpp
+++ b/clang/lib/Basic/Targets.cpp
@@ -2120,6 +2120,7 @@ void X86TargetInfo::getDefaultFeatures(llvm::StringMap<bool> &Features) const {
     setFeatureEnabledImpl(Features, "cx16", true);
     setFeatureEnabledImpl(Features, "lzcnt", true);
     setFeatureEnabledImpl(Features, "popcnt", true);
+    setFeatureEnabledImpl(Features, "prfchw", true);
     break;
   case CK_BTVER2:
     setFeatureEnabledImpl(Features, "avx", true);
@@ -2127,6 +2128,7 @@ void X86TargetInfo::getDefaultFeatures(llvm::StringMap<bool> &Features) const {
     setFeatureEnabledImpl(Features, "lzcnt", true);
     setFeatureEnabledImpl(Features, "aes", true);
     setFeatureEnabledImpl(Features, "pclmul", true);
+    setFeatureEnabledImpl(Features, "prfchw", true);
     setFeatureEnabledImpl(Features, "bmi", true);
     setFeatureEnabledImpl(Features, "f16c", true);
     setFeatureEnabledImpl(Features, "cx16", true);
@@ -2136,6 +2138,7 @@ void X86TargetInfo::getDefaultFeatures(llvm::StringMap<bool> &Features) const {
     setFeatureEnabledImpl(Features, "lzcnt", true);
     setFeatureEnabledImpl(Features, "aes", true);
     setFeatureEnabledImpl(Features, "pclmul", true);
+    setFeatureEnabledImpl(Features, "prfchw", true);
     setFeatureEnabledImpl(Features, "cx16", true);
     break;
   case CK_BDVER2:
@@ -2143,6 +2146,7 @@ void X86TargetInfo::getDefaultFeatures(llvm::StringMap<bool> &Features) const {
     setFeatureEnabledImpl(Features, "lzcnt", true);
     setFeatureEnabledImpl(Features, "aes", true);
     setFeatureEnabledImpl(Features, "pclmul", true);
+    setFeatureEnabledImpl(Features, "prfchw", true);
     setFeatureEnabledImpl(Features, "bmi", true);
     setFeatureEnabledImpl(Features, "fma", true);
     setFeatureEnabledImpl(Features, "f16c", true);
@@ -2467,6 +2471,13 @@ bool X86TargetInfo::HandleTargetFeatures(std::vector<std::string> &Features,
     Features.push_back("+popcnt");
   }
 
+  // Enable prfchw if 3DNow! is enabled and prfchw is not explicitly disabled.
+  if (!HasPRFCHW && MMX3DNowLevel >= AMD3DNow &&
+      std::find(Features.begin(), Features.end(), "-prfchw") == Features.end()){
+    HasPRFCHW = true;
+    Features.push_back("+prfchw");
+  }
+
   // LLVM doesn't have a separate switch for fpmath, so only accept it if it
   // matches the selected sse level.
   if (FPMath == FP_SSE && SSELevel < SSE1) {
diff --git a/clang/test/Preprocessor/predefined-arch-macros.c b/clang/test/Preprocessor/predefined-arch-macros.c
index bcfe90f29cb..45e317a3d8c 100644
--- a/clang/test/Preprocessor/predefined-arch-macros.c
+++ b/clang/test/Preprocessor/predefined-arch-macros.c
@@ -1166,6 +1166,7 @@
 // CHECK_BTVER1_M32: #define __LZCNT__ 1
 // CHECK_BTVER1_M32: #define __MMX__ 1
 // CHECK_BTVER1_M32: #define __POPCNT__ 1
+// CHECK_BTVER1_M32: #define __PRFCHW__ 1
 // CHECK_BTVER1_M32: #define __SSE2_MATH__ 1
 // CHECK_BTVER1_M32: #define __SSE2__ 1
 // CHECK_BTVER1_M32: #define __SSE3__ 1
@@ -1186,6 +1187,7 @@
 // CHECK_BTVER1_M64: #define __LZCNT__ 1
 // CHECK_BTVER1_M64: #define __MMX__ 1
 // CHECK_BTVER1_M64: #define __POPCNT__ 1
+// CHECK_BTVER1_M64: #define __PRFCHW__ 1
 // CHECK_BTVER1_M64: #define __SSE2_MATH__ 1
 // CHECK_BTVER1_M64: #define __SSE2__ 1
 // CHECK_BTVER1_M64: #define __SSE3__ 1
@@ -1210,6 +1212,7 @@
 // CHECK_BTVER2_M32: #define __LZCNT__ 1
 // CHECK_BTVER2_M32: #define __MMX__ 1
 // CHECK_BTVER2_M32: #define __POPCNT__ 1
+// CHECK_BTVER2_M32: #define __PRFCHW__ 1
 // CHECK_BTVER2_M32: #define __SSE2_MATH__ 1
 // CHECK_BTVER2_M32: #define __SSE2__ 1
 // CHECK_BTVER2_M32: #define __SSE3__ 1
@@ -1232,6 +1235,7 @@
 // CHECK_BTVER2_M64: #define __LZCNT__ 1
 // CHECK_BTVER2_M64: #define __MMX__ 1
 // CHECK_BTVER2_M64: #define __POPCNT__ 1
+// CHECK_BTVER2_M64: #define __PRFCHW__ 1
 // CHECK_BTVER2_M64: #define __SSE2_MATH__ 1
 // CHECK_BTVER2_M64: #define __SSE2__ 1
 // CHECK_BTVER2_M64: #define __SSE3__ 1
@@ -1258,6 +1262,7 @@
 // CHECK_BDVER1_M32: #define __MMX__ 1
 // CHECK_BDVER1_M32: #define __PCLMUL__ 1
 // CHECK_BDVER1_M32: #define __POPCNT__ 1
+// CHECK_BDVER1_M32: #define __PRFCHW__ 1
 // CHECK_BDVER1_M32: #define __SSE2_MATH__ 1
 // CHECK_BDVER1_M32: #define __SSE2__ 1
 // CHECK_BDVER1_M32: #define __SSE3__ 1
@@ -1285,6 +1290,7 @@
 // CHECK_BDVER1_M64: #define __MMX__ 1
 // CHECK_BDVER1_M64: #define __PCLMUL__ 1
 // CHECK_BDVER1_M64: #define __POPCNT__ 1
+// CHECK_BDVER1_M64: #define __PRFCHW__ 1
 // CHECK_BDVER1_M64: #define __SSE2_MATH__ 1
 // CHECK_BDVER1_M64: #define __SSE2__ 1
 // CHECK_BDVER1_M64: #define __SSE3__ 1
@@ -1317,6 +1323,7 @@
 // CHECK_BDVER2_M32: #define __MMX__ 1
 // CHECK_BDVER2_M32: #define __PCLMUL__ 1
 // CHECK_BDVER2_M32: #define __POPCNT__ 1
+// CHECK_BDVER2_M32: #define __PRFCHW__ 1
 // CHECK_BDVER2_M32: #define __SSE2_MATH__ 1
 // CHECK_BDVER2_M32: #define __SSE2__ 1
 // CHECK_BDVER2_M32: #define __SSE3__ 1
@@ -1348,6 +1355,7 @@
 // CHECK_BDVER2_M64: #define __MMX__ 1
 // CHECK_BDVER2_M64: #define __PCLMUL__ 1
 // CHECK_BDVER2_M64: #define __POPCNT__ 1
+// CHECK_BDVER2_M64: #define __PRFCHW__ 1
 // CHECK_BDVER2_M64: #define __SSE2_MATH__ 1
 // CHECK_BDVER2_M64: #define __SSE2__ 1
 // CHECK_BDVER2_M64: #define __SSE3__ 1
diff --git a/clang/test/Preprocessor/x86_target_features.c b/clang/test/Preprocessor/x86_target_features.c
index 40c4e6440c7..751c8ae9585 100644
--- a/clang/test/Preprocessor/x86_target_features.c
+++ b/clang/test/Preprocessor/x86_target_features.c
@@ -215,3 +215,24 @@
 // RUN: %clang -target i386-unknown-unknown -march=pentiumpro -mcx16 -x c -E -dM -o - %s | FileCheck --check-prefix=MCX16 %s
 
 // MCX16: #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_16 1
+
+// RUN: %clang -target i386-unknown-unknown -march=atom -mprfchw -x c -E -dM -o - %s | FileCheck --check-prefix=PRFCHW %s
+
+// PRFCHW: #define __PRFCHW__ 1
+
+// RUN: %clang -target i386-unknown-unknown -march=btver2 -mno-prfchw -x c -E -dM -o - %s | FileCheck --check-prefix=NOPRFCHW %s
+
+// NOPRFCHW-NOT: #define __PRFCHW__ 1
+
+// RUN: %clang -target i386-unknown-unknown -march=atom -m3dnow -x c -E -dM -o - %s | FileCheck --check-prefix=3DNOWPRFCHW %s
+
+// 3DNOWPRFCHW: #define __PRFCHW__ 1
+
+// RUN: %clang -target i386-unknown-unknown -march=atom -mno-prfchw -m3dnow -x c -E -dM -o - %s | FileCheck --check-prefix=3DNOWNOPRFCHW %s
+
+// 3DNOWNOPRFCHW-NOT: #define __PRFCHW__ 1
+
+// RUN: %clang -target i386-unknown-unknown -march=atom -mprfchw -mno-3dnow -x c -E -dM -o - %s | FileCheck --check-prefix=NO3DNOWPRFCHW %s
+
+// NO3DNOWPRFCHW: #define __PRFCHW__ 1
+