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Refactor. Global variables are part of compile unit so let CompileUni…
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…t create new global variable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137621 91177308-0d34-0410-b5e6-96231b3b80d8
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Devang Patel committed Aug 15, 2011
1 parent bb0752b commit 6f9d8ff
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Showing 5 changed files with 151 additions and 129 deletions.
7 changes: 7 additions & 0 deletions include/llvm/Analysis/DebugInfo.h
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Original file line number Diff line number Diff line change
Expand Up @@ -291,6 +291,9 @@ namespace llvm {
return getFieldAs<DIFile>(3).getFilename();
}

/// isUnsignedDIType - Return true if type encoding is unsigned.
bool isUnsignedDIType();

/// replaceAllUsesWith - Replace all uses of debug info referenced by
/// this descriptor.
void replaceAllUsesWith(DIDescriptor &D);
Expand Down Expand Up @@ -714,6 +717,10 @@ namespace llvm {
/// getDICompositeType - Find underlying composite type.
DICompositeType getDICompositeType(DIType T);

/// isSubprogramContext - Return true if Context is either a subprogram
/// or another context nested inside a subprogram.
bool isSubprogramContext(const MDNode *Context);

/// getOrInsertFnSpecificMDNode - Return a NameMDNode that is suitable
/// to hold function specific information.
NamedMDNode *getOrInsertFnSpecificMDNode(Module &M, StringRef Name);
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30 changes: 30 additions & 0 deletions lib/Analysis/DebugInfo.cpp
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Expand Up @@ -328,6 +328,22 @@ void DIType::replaceAllUsesWith(MDNode *D) {
}
}

/// isUnsignedDIType - Return true if type encoding is unsigned.
bool DIType::isUnsignedDIType() {
DIDerivedType DTy(DbgNode);
if (DTy.Verify())
return DTy.getTypeDerivedFrom().isUnsignedDIType();

DIBasicType BTy(DbgNode);
if (BTy.Verify()) {
unsigned Encoding = BTy.getEncoding();
if (Encoding == dwarf::DW_ATE_unsigned ||
Encoding == dwarf::DW_ATE_unsigned_char)
return true;
}
return false;
}

/// Verify - Verify that a compile unit is well formed.
bool DICompileUnit::Verify() const {
if (!DbgNode)
Expand Down Expand Up @@ -1014,3 +1030,17 @@ DICompositeType llvm::getDICompositeType(DIType T) {

return DICompositeType();
}

/// isSubprogramContext - Return true if Context is either a subprogram
/// or another context nested inside a subprogram.
bool llvm::isSubprogramContext(const MDNode *Context) {
if (!Context)
return false;
DIDescriptor D(Context);
if (D.isSubprogram())
return true;
if (D.isType())
return isSubprogramContext(DIType(Context).getContext());
return false;
}

109 changes: 109 additions & 0 deletions lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -16,7 +16,10 @@
#include "DwarfCompileUnit.h"
#include "DwarfDebug.h"
#include "llvm/Constants.h"
#include "llvm/GlobalVariable.h"
#include "llvm/Instructions.h"
#include "llvm/Analysis/DIBuilder.h"
#include "llvm/Target/Mangler.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetFrameLowering.h"
#include "llvm/Target/TargetMachine.h"
Expand Down Expand Up @@ -994,6 +997,112 @@ DIE *CompileUnit::getOrCreateSubprogramDIE(DISubprogram SP) {
return SPDie;
}

// Return const expression if value is a GEP to access merged global
// constant. e.g.
// i8* getelementptr ({ i8, i8, i8, i8 }* @_MergedGlobals, i32 0, i32 0)
static const ConstantExpr *getMergedGlobalExpr(const Value *V) {
const ConstantExpr *CE = dyn_cast_or_null<ConstantExpr>(V);
if (!CE || CE->getNumOperands() != 3 ||
CE->getOpcode() != Instruction::GetElementPtr)
return NULL;

// First operand points to a global struct.
Value *Ptr = CE->getOperand(0);
if (!isa<GlobalValue>(Ptr) ||
!isa<StructType>(cast<PointerType>(Ptr->getType())->getElementType()))
return NULL;

// Second operand is zero.
const ConstantInt *CI = dyn_cast_or_null<ConstantInt>(CE->getOperand(1));
if (!CI || !CI->isZero())
return NULL;

// Third operand is offset.
if (!isa<ConstantInt>(CE->getOperand(2)))
return NULL;

return CE;
}

/// createGlobalVariableDIE - create global variable DIE.
void CompileUnit::createGlobalVariableDIE(const MDNode *N) {
DIGlobalVariable GV(N);

// Check for pre-existence.
if (getDIE(GV))
return;

DIType GTy = GV.getType();
DIE *VariableDIE = new DIE(GV.getTag());

bool isGlobalVariable = GV.getGlobal() != NULL;

// Add name.
addString(VariableDIE, dwarf::DW_AT_name, dwarf::DW_FORM_string,
GV.getDisplayName());
StringRef LinkageName = GV.getLinkageName();
if (!LinkageName.empty() && isGlobalVariable)
addString(VariableDIE, dwarf::DW_AT_MIPS_linkage_name,
dwarf::DW_FORM_string,
getRealLinkageName(LinkageName));
// Add type.
addType(VariableDIE, GTy);

// Add scoping info.
if (!GV.isLocalToUnit()) {
addUInt(VariableDIE, dwarf::DW_AT_external, dwarf::DW_FORM_flag, 1);
// Expose as global.
addGlobal(GV.getName(), VariableDIE);
}
// Add line number info.
addSourceLine(VariableDIE, GV);
// Add to map.
insertDIE(N, VariableDIE);
// Add to context owner.
DIDescriptor GVContext = GV.getContext();
addToContextOwner(VariableDIE, GVContext);
// Add location.
if (isGlobalVariable) {
DIEBlock *Block = new (DIEValueAllocator) DIEBlock();
addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_addr);
addLabel(Block, 0, dwarf::DW_FORM_udata,
Asm->Mang->getSymbol(GV.getGlobal()));
// Do not create specification DIE if context is either compile unit
// or a subprogram.
if (GV.isDefinition() && !GVContext.isCompileUnit() &&
!GVContext.isFile() && !isSubprogramContext(GVContext)) {
// Create specification DIE.
DIE *VariableSpecDIE = new DIE(dwarf::DW_TAG_variable);
addDIEEntry(VariableSpecDIE, dwarf::DW_AT_specification,
dwarf::DW_FORM_ref4, VariableDIE);
addBlock(VariableSpecDIE, dwarf::DW_AT_location, 0, Block);
addUInt(VariableDIE, dwarf::DW_AT_declaration, dwarf::DW_FORM_flag,
1);
addDie(VariableSpecDIE);
} else {
addBlock(VariableDIE, dwarf::DW_AT_location, 0, Block);
}
} else if (const ConstantInt *CI =
dyn_cast_or_null<ConstantInt>(GV.getConstant()))
addConstantValue(VariableDIE, CI, GTy.isUnsignedDIType());
else if (const ConstantExpr *CE = getMergedGlobalExpr(N->getOperand(11))) {
// GV is a merged global.
DIEBlock *Block = new (DIEValueAllocator) DIEBlock();
Value *Ptr = CE->getOperand(0);
addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_addr);
addLabel(Block, 0, dwarf::DW_FORM_udata,
Asm->Mang->getSymbol(cast<GlobalValue>(Ptr)));
addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
SmallVector<Value*, 3> Idx(CE->op_begin()+1, CE->op_end());
addUInt(Block, 0, dwarf::DW_FORM_udata,
Asm->getTargetData().getIndexedOffset(Ptr->getType(), Idx));
addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_plus);
addBlock(VariableDIE, dwarf::DW_AT_location, 0, Block);
}

return;
}

/// constructSubrangeDIE - Construct subrange DIE from DISubrange.
void CompileUnit::constructSubrangeDIE(DIE &Buffer, DISubrange SR, DIE *IndexTy){
DIE *DW_Subrange = new DIE(dwarf::DW_TAG_subrange_type);
Expand Down
3 changes: 3 additions & 0 deletions lib/CodeGen/AsmPrinter/DwarfCompileUnit.h
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Original file line number Diff line number Diff line change
Expand Up @@ -250,6 +250,9 @@ class CompileUnit {
/// information entry.
DIEEntry *createDIEEntry(DIE *Entry);

/// createGlobalVariableDIE - create global variable DIE.
void createGlobalVariableDIE(const MDNode *N);

void addPubTypes(DISubprogram SP);

/// constructTypeDIE - Construct basic type die from DIBasicType.
Expand Down
131 changes: 2 additions & 129 deletions lib/CodeGen/AsmPrinter/DwarfDebug.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -24,7 +24,6 @@
#include "llvm/MC/MCSection.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Target/Mangler.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetFrameLowering.h"
#include "llvm/Target/TargetLoweringObjectFile.h"
Expand Down Expand Up @@ -179,19 +178,6 @@ static StringRef getRealLinkageName(StringRef LinkageName) {
return LinkageName;
}

/// isSubprogramContext - Return true if Context is either a subprogram
/// or another context nested inside a subprogram.
static bool isSubprogramContext(const MDNode *Context) {
if (!Context)
return false;
DIDescriptor D(Context);
if (D.isSubprogram())
return true;
if (D.isType())
return isSubprogramContext(DIType(Context).getContext());
return false;
}

/// updateSubprogramScopeDIE - Find DIE for the given subprogram and
/// attach appropriate DW_AT_low_pc and DW_AT_high_pc attributes.
/// If there are global variables in this scope then create and insert
Expand Down Expand Up @@ -385,22 +371,6 @@ DIE *DwarfDebug::constructInlinedScopeDIE(LexicalScope *Scope) {
return ScopeDIE;
}

/// isUnsignedDIType - Return true if type encoding is unsigned.
static bool isUnsignedDIType(DIType Ty) {
DIDerivedType DTy(Ty);
if (DTy.Verify())
return isUnsignedDIType(DTy.getTypeDerivedFrom());

DIBasicType BTy(Ty);
if (BTy.Verify()) {
unsigned Encoding = BTy.getEncoding();
if (Encoding == dwarf::DW_ATE_unsigned ||
Encoding == dwarf::DW_ATE_unsigned_char)
return true;
}
return false;
}

/// constructVariableDIE - Construct a DIE for the given DbgVariable.
DIE *DwarfDebug::constructVariableDIE(DbgVariable *DV, LexicalScope *Scope) {
StringRef Name = DV->getName();
Expand Down Expand Up @@ -504,7 +474,7 @@ DIE *DwarfDebug::constructVariableDIE(DbgVariable *DV, LexicalScope *Scope) {
updated =
VariableCU->addConstantValue(VariableDie,
DVInsn->getOperand(0).getCImm(),
isUnsignedDIType(DV->getType()));
DV->getType().isUnsignedDIType());
} else {
VariableCU->addVariableAddress(DV, VariableDie,
Asm->getDebugValueLocation(DVInsn));
Expand Down Expand Up @@ -701,33 +671,6 @@ CompileUnit *DwarfDebug::getCompileUnit(const MDNode *N) const {
return I->second;
}

// Return const expression if value is a GEP to access merged global
// constant. e.g.
// i8* getelementptr ({ i8, i8, i8, i8 }* @_MergedGlobals, i32 0, i32 0)
static const ConstantExpr *getMergedGlobalExpr(const Value *V) {
const ConstantExpr *CE = dyn_cast_or_null<ConstantExpr>(V);
if (!CE || CE->getNumOperands() != 3 ||
CE->getOpcode() != Instruction::GetElementPtr)
return NULL;

// First operand points to a global struct.
Value *Ptr = CE->getOperand(0);
if (!isa<GlobalValue>(Ptr) ||
!isa<StructType>(cast<PointerType>(Ptr->getType())->getElementType()))
return NULL;

// Second operand is zero.
const ConstantInt *CI = dyn_cast_or_null<ConstantInt>(CE->getOperand(1));
if (!CI || !CI->isZero())
return NULL;

// Third operand is offset.
if (!isa<ConstantInt>(CE->getOperand(2)))
return NULL;

return CE;
}

/// constructGlobalVariableDIE - Construct global variable DIE.
void DwarfDebug::constructGlobalVariableDIE(const MDNode *N) {
DIGlobalVariable GV(N);
Expand All @@ -738,77 +681,7 @@ void DwarfDebug::constructGlobalVariableDIE(const MDNode *N) {

// Check for pre-existence.
CompileUnit *TheCU = getCompileUnit(N);
if (TheCU->getDIE(GV))
return;

DIType GTy = GV.getType();
DIE *VariableDIE = new DIE(GV.getTag());

bool isGlobalVariable = GV.getGlobal() != NULL;

// Add name.
TheCU->addString(VariableDIE, dwarf::DW_AT_name, dwarf::DW_FORM_string,
GV.getDisplayName());
StringRef LinkageName = GV.getLinkageName();
if (!LinkageName.empty() && isGlobalVariable)
TheCU->addString(VariableDIE, dwarf::DW_AT_MIPS_linkage_name,
dwarf::DW_FORM_string,
getRealLinkageName(LinkageName));
// Add type.
TheCU->addType(VariableDIE, GTy);

// Add scoping info.
if (!GV.isLocalToUnit()) {
TheCU->addUInt(VariableDIE, dwarf::DW_AT_external, dwarf::DW_FORM_flag, 1);
// Expose as global.
TheCU->addGlobal(GV.getName(), VariableDIE);
}
// Add line number info.
TheCU->addSourceLine(VariableDIE, GV);
// Add to map.
TheCU->insertDIE(N, VariableDIE);
// Add to context owner.
DIDescriptor GVContext = GV.getContext();
TheCU->addToContextOwner(VariableDIE, GVContext);
// Add location.
if (isGlobalVariable) {
DIEBlock *Block = new (DIEValueAllocator) DIEBlock();
TheCU->addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_addr);
TheCU->addLabel(Block, 0, dwarf::DW_FORM_udata,
Asm->Mang->getSymbol(GV.getGlobal()));
// Do not create specification DIE if context is either compile unit
// or a subprogram.
if (GV.isDefinition() && !GVContext.isCompileUnit() &&
!GVContext.isFile() && !isSubprogramContext(GVContext)) {
// Create specification DIE.
DIE *VariableSpecDIE = new DIE(dwarf::DW_TAG_variable);
TheCU->addDIEEntry(VariableSpecDIE, dwarf::DW_AT_specification,
dwarf::DW_FORM_ref4, VariableDIE);
TheCU->addBlock(VariableSpecDIE, dwarf::DW_AT_location, 0, Block);
TheCU->addUInt(VariableDIE, dwarf::DW_AT_declaration, dwarf::DW_FORM_flag,
1);
TheCU->addDie(VariableSpecDIE);
} else {
TheCU->addBlock(VariableDIE, dwarf::DW_AT_location, 0, Block);
}
} else if (const ConstantInt *CI =
dyn_cast_or_null<ConstantInt>(GV.getConstant()))
TheCU->addConstantValue(VariableDIE, CI, isUnsignedDIType(GTy));
else if (const ConstantExpr *CE = getMergedGlobalExpr(N->getOperand(11))) {
// GV is a merged global.
DIEBlock *Block = new (DIEValueAllocator) DIEBlock();
Value *Ptr = CE->getOperand(0);
TheCU->addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_addr);
TheCU->addLabel(Block, 0, dwarf::DW_FORM_udata,
Asm->Mang->getSymbol(cast<GlobalValue>(Ptr)));
TheCU->addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
SmallVector<Value*, 3> Idx(CE->op_begin()+1, CE->op_end());
TheCU->addUInt(Block, 0, dwarf::DW_FORM_udata,
Asm->getTargetData().getIndexedOffset(Ptr->getType(), Idx));
TheCU->addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_plus);
TheCU->addBlock(VariableDIE, dwarf::DW_AT_location, 0, Block);
}

TheCU->createGlobalVariableDIE(N);
return;
}

Expand Down

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