Fix setting and default setting of code model for jit. Do this

by allowing backends to override routines that will default
the JIT and Static code generation to an appropriate code model
for the architecture.

Should fix PR 5773.

llvm-svn: 91824

include/llvm/Target/TargetMachine.h

@@ -292,6 +292,13 @@ protected: // Can only create subclasses.
   ///
   bool addCommonCodeGenPasses(PassManagerBase &, CodeGenOpt::Level);
 
+private:
+  // These routines are used by addPassesToEmitFileFinish and
+  // addPassesToEmitMachineCode to set the CodeModel if it's still marked
+  // as default.
+  virtual void setCodeModelForJIT();
+  virtual void setCodeModelForStatic();
+  
 public:
   
   /// addPassesToEmitFile - Add passes to the specified pass manager to get the

lib/CodeGen/LLVMTargetMachine.cpp

@@ -83,7 +83,18 @@ LLVMTargetMachine::LLVMTargetMachine(const Target &T,
   AsmInfo = T.createAsmInfo(TargetTriple);
 }
 
+// Set the default code model for the JIT for a generic target.
+// FIXME: Is small right here? or .is64Bit() ? Large : Small?
+void
+LLVMTargetMachine::setCodeModelForJIT() {
+  setCodeModel(CodeModel::Small);
+}
 
+// Set the default code model for static compilation for a generic target.
+void
+LLVMTargetMachine::setCodeModelForStatic() {
+  setCodeModel(CodeModel::Small);
+}
 
 FileModel::Model
 LLVMTargetMachine::addPassesToEmitFile(PassManagerBase &PM,
@@ -130,6 +141,9 @@ bool LLVMTargetMachine::addAssemblyEmitter(PassManagerBase &PM,
 bool LLVMTargetMachine::addPassesToEmitFileFinish(PassManagerBase &PM,
                                                   MachineCodeEmitter *MCE,
                                                   CodeGenOpt::Level OptLevel) {
+  // Make sure the code model is set.
+  setCodeModelForStatic();
+  
   if (MCE)
     addSimpleCodeEmitter(PM, OptLevel, *MCE);
   if (PrintEmittedAsm)
@@ -146,6 +160,9 @@ bool LLVMTargetMachine::addPassesToEmitFileFinish(PassManagerBase &PM,
 bool LLVMTargetMachine::addPassesToEmitFileFinish(PassManagerBase &PM,
                                                   JITCodeEmitter *JCE,
                                                   CodeGenOpt::Level OptLevel) {
+  // Make sure the code model is set.
+  setCodeModelForJIT();
+  
   if (JCE)
     addSimpleCodeEmitter(PM, OptLevel, *JCE);
   if (PrintEmittedAsm)
@@ -162,6 +179,9 @@ bool LLVMTargetMachine::addPassesToEmitFileFinish(PassManagerBase &PM,
 bool LLVMTargetMachine::addPassesToEmitFileFinish(PassManagerBase &PM,
                                                   ObjectCodeEmitter *OCE,
                                                   CodeGenOpt::Level OptLevel) {
+  // Make sure the code model is set.
+  setCodeModelForStatic();
+  
   if (OCE)
     addSimpleCodeEmitter(PM, OptLevel, *OCE);
   if (PrintEmittedAsm)
@@ -181,6 +201,9 @@ bool LLVMTargetMachine::addPassesToEmitFileFinish(PassManagerBase &PM,
 bool LLVMTargetMachine::addPassesToEmitMachineCode(PassManagerBase &PM,
                                                    MachineCodeEmitter &MCE,
                                                    CodeGenOpt::Level OptLevel) {
+  // Make sure the code model is set.
+  setCodeModelForJIT();
+  
   // Add common CodeGen passes.
   if (addCommonCodeGenPasses(PM, OptLevel))
     return true;
@@ -203,6 +226,9 @@ bool LLVMTargetMachine::addPassesToEmitMachineCode(PassManagerBase &PM,
 bool LLVMTargetMachine::addPassesToEmitMachineCode(PassManagerBase &PM,
                                                    JITCodeEmitter &JCE,
                                                    CodeGenOpt::Level OptLevel) {
+  // Make sure the code model is set.
+  setCodeModelForJIT();
+  
   // Add common CodeGen passes.
   if (addCommonCodeGenPasses(PM, OptLevel))
     return true;

lib/Target/Mips/MipsTargetMachine.cpp

@@ -50,11 +50,6 @@ MipsTargetMachine(const Target &T, const std::string &TT, const std::string &FS,
     else
       setRelocationModel(Reloc::Static);
   }
-
-  // TODO: create an option to enable long calls, like -mlong-calls, 
-  // that would be our CodeModel::Large. It must not work with Abicall.
-  if (getCodeModel() == CodeModel::Default)
-    setCodeModel(CodeModel::Small);
 }
 
 MipselTargetMachine::

lib/Target/X86/X86TargetMachine.cpp

@@ -95,10 +95,6 @@ X86TargetMachine::X86TargetMachine(const Target &T, const std::string &TT,
   assert(getRelocationModel() != Reloc::Default &&
          "Relocation mode not picked");
 
-  // If no code model is picked, default to small.
-  if (getCodeModel() == CodeModel::Default)
-    setCodeModel(CodeModel::Small);
-      
   // ELF and X86-64 don't have a distinct DynamicNoPIC model.  DynamicNoPIC
   // is defined as a model for code which may be used in static or dynamic
   // executables but not necessarily a shared library. On X86-32 we just
@@ -188,10 +184,6 @@ bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
     Subtarget.setPICStyle(PICStyles::None);
   }
   
-  // 64-bit JIT places everything in the same buffer except external functions.
-  if (Subtarget.is64Bit())
-      setCodeModel(CodeModel::Large);
-
   PM.add(createX86CodeEmitterPass(*this, MCE));
 
   return false;
@@ -208,9 +200,6 @@ bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
     Subtarget.setPICStyle(PICStyles::None);
   }
   
-  // 64-bit JIT places everything in the same buffer except external functions.
-  if (Subtarget.is64Bit())
-      setCodeModel(CodeModel::Large);
 
   PM.add(createX86JITCodeEmitterPass(*this, JCE));
 
@@ -244,3 +233,23 @@ bool X86TargetMachine::addSimpleCodeEmitter(PassManagerBase &PM,
   PM.add(createX86ObjectCodeEmitterPass(*this, OCE));
   return false;
 }
+
+void X86TargetMachine::setCodeModelForStatic() {
+
+    if (getCodeModel() != CodeModel::Default) return;
+
+    // For static codegen, if we're not already set, use Small codegen.
+    setCodeModel(CodeModel::Small);
+}
+
+
+void X86TargetMachine::setCodeModelForJIT() {
+
+  if (getCodeModel() != CodeModel::Default) return;
+
+  // 64-bit JIT places everything in the same buffer except external functions.
+  if (Subtarget.is64Bit())
+    setCodeModel(CodeModel::Large);
+  else
+    setCodeModel(CodeModel::Small);
+}

lib/Target/X86/X86TargetMachine.h

@@ -38,6 +38,11 @@ class X86TargetMachine : public LLVMTargetMachine {
   X86ELFWriterInfo  ELFWriterInfo;
   Reloc::Model      DefRelocModel; // Reloc model before it's overridden.
 
+private:
+  // We have specific defaults for X86.
+  virtual void setCodeModelForJIT();
+  virtual void setCodeModelForStatic();
+  
 public:
   X86TargetMachine(const Target &T, const std::string &TT, 
                    const std::string &FS, bool is64Bit);