Revert 51b0da73 "Recommit "[X86] Merge the FEATURE_64BIT and FEATURE_EM64T bits in X86TargetParser.def.""

It gets miscompiled with GCC 5.3, causing Clang to crash with
"error: unknown target CPU 'x86-64'"

See the llvm-commits thread for reproduction steps.

This reverts commit 51b0da731af75c68dd521e04cc576d5a611b1612.

1 files changed, 16 insertions, 27 deletions

diff --git a/llvm/lib/Support/X86TargetParser.cpp b/llvm/lib/Support/X86TargetParser.cpp
index 7e87d65a..261e296 100644
--- a/llvm/lib/Support/X86TargetParser.cpp
+++ b/llvm/lib/Support/X86TargetParser.cpp
@@ -48,14 +48,6 @@ public:
     return (Bits[I / 32] & Mask) != 0;
   }
 
-  constexpr FeatureBitset &operator&=(const FeatureBitset &RHS) {
-    for (unsigned I = 0, E = array_lengthof(Bits); I != E; ++I) {
-      uint32_t NewBits = Bits[I] & RHS.Bits[I];
-      Bits[I] = NewBits;
-    }
-    return *this;
-  }
-
   constexpr FeatureBitset &operator|=(const FeatureBitset &RHS) {
     for (unsigned I = 0, E = array_lengthof(Bits); I != E; ++I) {
       uint32_t NewBits = Bits[I] | RHS.Bits[I];
@@ -65,14 +57,16 @@ public:
   }
 
   constexpr FeatureBitset operator&(const FeatureBitset &RHS) const {
-    FeatureBitset Result = *this;
-    Result &= RHS;
+    FeatureBitset Result;
+    for (unsigned I = 0, E = array_lengthof(Bits); I != E; ++I)
+      Result.Bits[I] = Bits[I] & RHS.Bits[I];
     return Result;
   }
 
   constexpr FeatureBitset operator|(const FeatureBitset &RHS) const {
-    FeatureBitset Result = *this;
-    Result |= RHS;
+    FeatureBitset Result;
+    for (unsigned I = 0, E = array_lengthof(Bits); I != E; ++I)
+      Result.Bits[I] = Bits[I] | RHS.Bits[I];
     return Result;
   }
 
@@ -117,10 +111,10 @@ static constexpr FeatureBitset FeaturesPentium4 =
 static constexpr FeatureBitset FeaturesPrescott =
     FeaturesPentium4 | FeatureSSE3;
 static constexpr FeatureBitset FeaturesNocona =
-    FeaturesPrescott | Feature64BIT | FeatureCMPXCHG16B;
+    FeaturesPrescott | FeatureEM64T | FeatureCMPXCHG16B;
 
 // Basic 64-bit capable CPU.
-static constexpr FeatureBitset FeaturesX86_64 = FeaturesPentium4 | Feature64BIT;
+static constexpr FeatureBitset FeaturesX86_64 = FeaturesPentium4 | FeatureEM64T;
 
 // Intel Core CPUs
 static constexpr FeatureBitset FeaturesCore2 =
@@ -207,7 +201,7 @@ static constexpr FeatureBitset FeaturesAthlon =
 static constexpr FeatureBitset FeaturesAthlonXP =
     FeaturesAthlon | FeatureFXSR | FeatureSSE;
 static constexpr FeatureBitset FeaturesK8 =
-    FeaturesAthlonXP | FeatureSSE2 | Feature64BIT;
+    FeaturesAthlonXP | FeatureSSE2 | FeatureEM64T;
 static constexpr FeatureBitset FeaturesK8SSE3 = FeaturesK8 | FeatureSSE3;
 static constexpr FeatureBitset FeaturesAMDFAM10 =
     FeaturesK8SSE3 | FeatureCMPXCHG16B | FeatureLZCNT | FeaturePOPCNT |
@@ -215,7 +209,7 @@ static constexpr FeatureBitset FeaturesAMDFAM10 =
 
 // Bobcat architecture processors.
 static constexpr FeatureBitset FeaturesBTVER1 =
-    FeatureX87 | FeatureCMPXCHG8B | FeatureCMPXCHG16B | Feature64BIT |
+    FeatureX87 | FeatureCMPXCHG8B | FeatureCMPXCHG16B | FeatureEM64T |
     FeatureFXSR | FeatureLZCNT | FeatureMMX | FeaturePOPCNT | FeaturePRFCHW |
     FeatureSSE | FeatureSSE2 | FeatureSSE3 | FeatureSSSE3 | FeatureSSE4_A |
     FeatureSAHF;
@@ -226,7 +220,7 @@ static constexpr FeatureBitset FeaturesBTVER2 =
 // AMD Bulldozer architecture processors.
 static constexpr FeatureBitset FeaturesBDVER1 =
     FeatureX87 | FeatureAES | FeatureAVX | FeatureCMPXCHG8B |
-    FeatureCMPXCHG16B | Feature64BIT | FeatureFMA4 | FeatureFXSR | FeatureLWP |
+    FeatureCMPXCHG16B | FeatureEM64T | FeatureFMA4 | FeatureFXSR | FeatureLWP |
     FeatureLZCNT | FeatureMMX | FeaturePCLMUL | FeaturePOPCNT | FeaturePRFCHW |
     FeatureSAHF | FeatureSSE | FeatureSSE2 | FeatureSSE3 | FeatureSSSE3 |
     FeatureSSE4_1 | FeatureSSE4_2 | FeatureSSE4_A | FeatureXOP | FeatureXSAVE;
@@ -242,7 +236,7 @@ static constexpr FeatureBitset FeaturesBDVER4 =
 static constexpr FeatureBitset FeaturesZNVER1 =
     FeatureX87 | FeatureADX | FeatureAES | FeatureAVX | FeatureAVX2 |
     FeatureBMI | FeatureBMI2 | FeatureCLFLUSHOPT | FeatureCLZERO |
-    FeatureCMPXCHG8B | FeatureCMPXCHG16B | Feature64BIT | FeatureF16C |
+    FeatureCMPXCHG8B | FeatureCMPXCHG16B | FeatureEM64T | FeatureF16C |
     FeatureFMA | FeatureFSGSBASE | FeatureFXSR | FeatureLZCNT | FeatureMMX |
     FeatureMOVBE | FeatureMWAITX | FeaturePCLMUL | FeaturePOPCNT |
     FeaturePRFCHW | FeatureRDRND | FeatureRDSEED | FeatureSAHF | FeatureSHA |
@@ -369,7 +363,7 @@ static constexpr ProcInfo Processors[] = {
 
 X86::CPUKind llvm::X86::parseArchX86(StringRef CPU, bool Only64Bit) {
   for (const auto &P : Processors)
-    if (P.Name == CPU && (P.Features[FEATURE_64BIT] || !Only64Bit))
+    if (P.Name == CPU && (P.Features[FEATURE_EM64T] || !Only64Bit))
       return P.Kind;
 
   return CK_None;
@@ -378,7 +372,7 @@ X86::CPUKind llvm::X86::parseArchX86(StringRef CPU, bool Only64Bit) {
 void llvm::X86::fillValidCPUArchList(SmallVectorImpl<StringRef> &Values,
                                      bool Only64Bit) {
   for (const auto &P : Processors)
-    if (!P.Name.empty() && (P.Features[FEATURE_64BIT] || !Only64Bit))
+    if (!P.Name.empty() && (P.Features[FEATURE_EM64T] || !Only64Bit))
       Values.emplace_back(P.Name);
 }
 
@@ -407,6 +401,7 @@ static constexpr FeatureBitset ImpliedFeaturesCLZERO = {};
 static constexpr FeatureBitset ImpliedFeaturesCMOV = {};
 static constexpr FeatureBitset ImpliedFeaturesCMPXCHG16B = {};
 static constexpr FeatureBitset ImpliedFeaturesCMPXCHG8B = {};
+static constexpr FeatureBitset ImpliedFeaturesEM64T = {};
 static constexpr FeatureBitset ImpliedFeaturesENQCMD = {};
 static constexpr FeatureBitset ImpliedFeaturesFSGSBASE = {};
 static constexpr FeatureBitset ImpliedFeaturesFXSR = {};
@@ -532,14 +527,8 @@ void llvm::X86::getFeaturesForCPU(StringRef CPU,
                          [&](const ProcInfo &P) { return P.Name == CPU; });
   assert(I != std::end(Processors) && "Processor not found!");
 
-  FeatureBitset Bits = I->Features;
-
-  // Remove the 64-bit feature which we only use to validate if a CPU can
-  // be used with 64-bit mode.
-  Bits &= ~Feature64BIT;
-
   // Add the string version of all set bits.
-  getFeatureBitsAsStrings(Bits, EnabledFeatures);
+  getFeatureBitsAsStrings(I->Features, EnabledFeatures);
 }
 
 // For each feature that is (transitively) implied by this feature, set it.