Fix a use of uninitialized value. OldCC is set when IsCmpZero || IsSwapped and read...

[oota-llvm.git] / lib / Target / X86 / X86Subtarget.cpp

diff --git a/lib/Target/X86/X86Subtarget.cpp b/lib/Target/X86/X86Subtarget.cpp
index 08edc6133089a5fcee466280d89d8f78f35aea7d..989e0d61b6fcdfd66443731ea8d70a5b074a9523 100644 (file)
--- a/lib/Target/X86/X86Subtarget.cpp
+++ b/lib/Target/X86/X86Subtarget.cpp
@@ -16,6 +16,7 @@
 #include "llvm/IR/Attributes.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/GlobalValue.h"
+#include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/Host.h"
@@ -35,6 +36,13 @@ using namespace llvm;
 #define GET_SUBTARGETINFO_CTOR
 #include "X86GenSubtargetInfo.inc"
 
+// Temporary option to control early if-conversion for x86 while adding machine
+// models.
+static cl::opt<bool>
+X86EarlyIfConv("x86-early-ifcvt", cl::Hidden,
+               cl::desc("Enable early if-conversion on X86"));
+
+
 /// ClassifyBlockAddressReference - Classify a blockaddress reference for the
 /// current subtarget according to how we should reference it in a non-pcrel
 /// context.
@@ -154,7 +162,7 @@ const char *X86Subtarget::getBZeroEntry() const {
       !getTargetTriple().isMacOSXVersionLT(10, 6))
     return "__bzero";
 
-  return 0;
+  return nullptr;
 }
 
 bool X86Subtarget::hasSinCos() const {
@@ -176,14 +184,14 @@ bool X86Subtarget::IsLegalToCallImmediateAddr(const TargetMachine &TM) const {
 
 void X86Subtarget::resetSubtargetFeatures(const MachineFunction *MF) {
   AttributeSet FnAttrs = MF->getFunction()->getAttributes();
-  Attribute CPUAttr = FnAttrs.getAttribute(AttributeSet::FunctionIndex,
-                                           "target-cpu");
-  Attribute FSAttr = FnAttrs.getAttribute(AttributeSet::FunctionIndex,
-                                          "target-features");
+  Attribute CPUAttr =
+      FnAttrs.getAttribute(AttributeSet::FunctionIndex, "target-cpu");
+  Attribute FSAttr =
+      FnAttrs.getAttribute(AttributeSet::FunctionIndex, "target-features");
   std::string CPU =
-    !CPUAttr.hasAttribute(Attribute::None) ?CPUAttr.getValueAsString() : "";
+      !CPUAttr.hasAttribute(Attribute::None) ? CPUAttr.getValueAsString() : "";
   std::string FS =
-    !FSAttr.hasAttribute(Attribute::None) ? FSAttr.getValueAsString() : "";
+      !FSAttr.hasAttribute(Attribute::None) ? FSAttr.getValueAsString() : "";
   if (!FS.empty()) {
     initializeEnvironment();
     resetSubtargetFeatures(CPU, FS);
@@ -282,33 +290,36 @@ void X86Subtarget::initializeEnvironment() {
   PadShortFunctions = false;
   CallRegIndirect = false;
   LEAUsesAG = false;
+  SlowLEA = false;
   stackAlignment = 4;
   // FIXME: this is a known good value for Yonah. How about others?
   MaxInlineSizeThreshold = 128;
 }
 
 X86Subtarget::X86Subtarget(const std::string &TT, const std::string &CPU,
-                           const std::string &FS,
-                           unsigned StackAlignOverride)
-  : X86GenSubtargetInfo(TT, CPU, FS)
-  , X86ProcFamily(Others)
-  , PICStyle(PICStyles::None)
-  , TargetTriple(TT)
-  , StackAlignOverride(StackAlignOverride)
-  , In64BitMode(TargetTriple.getArch() == Triple::x86_64)
-  , In32BitMode(TargetTriple.getArch() == Triple::x86 &&
-                TargetTriple.getEnvironment() != Triple::CODE16)
-  , In16BitMode(TargetTriple.getArch() == Triple::x86 &&
-                TargetTriple.getEnvironment() == Triple::CODE16) {
+                           const std::string &FS, unsigned StackAlignOverride)
+    : X86GenSubtargetInfo(TT, CPU, FS), X86ProcFamily(Others),
+      PICStyle(PICStyles::None), TargetTriple(TT),
+      StackAlignOverride(StackAlignOverride),
+      In64BitMode(TargetTriple.getArch() == Triple::x86_64),
+      In32BitMode(TargetTriple.getArch() == Triple::x86 &&
+                  TargetTriple.getEnvironment() != Triple::CODE16),
+      In16BitMode(TargetTriple.getArch() == Triple::x86 &&
+                  TargetTriple.getEnvironment() == Triple::CODE16) {
   initializeEnvironment();
   resetSubtargetFeatures(CPU, FS);
 }
 
-bool X86Subtarget::enablePostRAScheduler(
-           CodeGenOpt::Level OptLevel,
-           TargetSubtargetInfo::AntiDepBreakMode& Mode,
-           RegClassVector& CriticalPathRCs) const {
+bool
+X86Subtarget::enablePostRAScheduler(CodeGenOpt::Level OptLevel,
+                                    TargetSubtargetInfo::AntiDepBreakMode &Mode,
+                                    RegClassVector &CriticalPathRCs) const {
   Mode = TargetSubtargetInfo::ANTIDEP_CRITICAL;
   CriticalPathRCs.clear();
   return PostRAScheduler && OptLevel >= CodeGenOpt::Default;
 }
+
+bool
+X86Subtarget::enableEarlyIfConversion() const {
+  return hasCMov() && X86EarlyIfConv;
+}