Teach ISel not to optimize 'optnone' functions (revised).

[oota-llvm.git] / lib / Target / TargetMachine.cpp

diff --git a/lib/Target/TargetMachine.cpp b/lib/Target/TargetMachine.cpp
index 19819b886c11e38e794e4d1bfd3a430172dc1e34..9ba78bce7f9c6eee7d768165f33035c6d941ced3 100644 (file)
--- a/lib/Target/TargetMachine.cpp
+++ b/lib/Target/TargetMachine.cpp
@@ -11,9 +11,14 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/MC/MCAsmInfo.h"
 #include "llvm/Target/TargetMachine.h"
-#include "llvm/Target/TargetOptions.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/GlobalAlias.h"
+#include "llvm/IR/GlobalValue.h"
+#include "llvm/IR/GlobalVariable.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCCodeGenInfo.h"
 #include "llvm/Support/CommandLine.h"
 using namespace llvm;
 
@@ -22,8 +27,6 @@ using namespace llvm;
 //
 
 namespace llvm {
-  bool StrongPHIElim;
-  bool EnableMachineSched;
   bool HasDivModLibcall;
   bool AsmVerbosityDefault(false);
 }
@@ -60,6 +63,29 @@ TargetMachine::~TargetMachine() {
   delete AsmInfo;
 }
 
+/// \brief Reset the target options based on the function's attributes.
+void TargetMachine::resetTargetOptions(const MachineFunction *MF) const {
+  const Function *F = MF->getFunction();
+  TargetOptions &TO = MF->getTarget().Options;
+
+#define RESET_OPTION(X, Y)                                              \
+  do {                                                                  \
+    if (F->hasFnAttribute(Y))                                           \
+      TO.X =                                                            \
+        (F->getAttributes().                                            \
+           getAttribute(AttributeSet::FunctionIndex,                    \
+                        Y).getValueAsString() == "true");               \
+  } while (0)
+
+  RESET_OPTION(NoFramePointerElim, "no-frame-pointer-elim");
+  RESET_OPTION(LessPreciseFPMADOption, "less-precise-fpmad");
+  RESET_OPTION(UnsafeFPMath, "unsafe-fp-math");
+  RESET_OPTION(NoInfsFPMath, "no-infs-fp-math");
+  RESET_OPTION(NoNaNsFPMath, "no-nans-fp-math");
+  RESET_OPTION(UseSoftFloat, "use-soft-float");
+  RESET_OPTION(DisableTailCalls, "disable-tail-calls");
+}
+
 /// getRelocationModel - Returns the code generation relocation model. The
 /// choices are static, PIC, and dynamic-no-pic, and target default.
 Reloc::Model TargetMachine::getRelocationModel() const {
@@ -76,6 +102,60 @@ CodeModel::Model TargetMachine::getCodeModel() const {
   return CodeGenInfo->getCodeModel();
 }
 
+/// Get the IR-specified TLS model for Var.
+static TLSModel::Model getSelectedTLSModel(const GlobalVariable *Var) {
+  switch (Var->getThreadLocalMode()) {
+  case GlobalVariable::NotThreadLocal:
+    llvm_unreachable("getSelectedTLSModel for non-TLS variable");
+    break;
+  case GlobalVariable::GeneralDynamicTLSModel:
+    return TLSModel::GeneralDynamic;
+  case GlobalVariable::LocalDynamicTLSModel:
+    return TLSModel::LocalDynamic;
+  case GlobalVariable::InitialExecTLSModel:
+    return TLSModel::InitialExec;
+  case GlobalVariable::LocalExecTLSModel:
+    return TLSModel::LocalExec;
+  }
+  llvm_unreachable("invalid TLS model");
+}
+
+TLSModel::Model TargetMachine::getTLSModel(const GlobalValue *GV) const {
+  // If GV is an alias then use the aliasee for determining
+  // thread-localness.
+  if (const GlobalAlias *GA = dyn_cast<GlobalAlias>(GV))
+    GV = GA->resolveAliasedGlobal(false);
+  const GlobalVariable *Var = cast<GlobalVariable>(GV);
+
+  bool isLocal = Var->hasLocalLinkage();
+  bool isDeclaration = Var->isDeclaration();
+  bool isPIC = getRelocationModel() == Reloc::PIC_;
+  bool isPIE = Options.PositionIndependentExecutable;
+  // FIXME: what should we do for protected and internal visibility?
+  // For variables, is internal different from hidden?
+  bool isHidden = Var->hasHiddenVisibility();
+
+  TLSModel::Model Model;
+  if (isPIC && !isPIE) {
+    if (isLocal || isHidden)
+      Model = TLSModel::LocalDynamic;
+    else
+      Model = TLSModel::GeneralDynamic;
+  } else {
+    if (!isDeclaration || isHidden)
+      Model = TLSModel::LocalExec;
+    else
+      Model = TLSModel::InitialExec;
+  }
+
+  // If the user specified a more specific model, use that.
+  TLSModel::Model SelectedModel = getSelectedTLSModel(Var);
+  if (SelectedModel > Model)
+    return SelectedModel;
+
+  return Model;
+}
+
 /// getOptLevel - Returns the optimization level: None, Less,
 /// Default, or Aggressive.
 CodeGenOpt::Level TargetMachine::getOptLevel() const {
@@ -84,6 +164,11 @@ CodeGenOpt::Level TargetMachine::getOptLevel() const {
   return CodeGenInfo->getOptLevel();
 }
 
+void TargetMachine::setOptLevel(CodeGenOpt::Level Level) const {
+  if (CodeGenInfo)
+    CodeGenInfo->setOptLevel(Level);
+}
+
 bool TargetMachine::getAsmVerbosityDefault() {
   return AsmVerbosityDefault;
 }
@@ -107,4 +192,3 @@ void TargetMachine::setFunctionSections(bool V) {
 void TargetMachine::setDataSections(bool V) {
   DataSections = V;
 }
-