Add DebugInfoBuilder. Patch by Talin!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55409 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 423 insertions, 0 deletions

diff --git a/include/llvm/Support/DebugInfoBuilder.h b/include/llvm/Support/DebugInfoBuilder.h
new file mode 100644
index 0000000000..875ae4180f
--- /dev/null
+++ b/include/llvm/Support/DebugInfoBuilder.h
@@ -0,0 +1,151 @@
+//===-- llvm/Support/DebugInfoBuilder.h - -----------------------*- C++ -*-===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+//
+// This file contains the declaration of the DebugInfoBuilder class, which is
+// a helper class used to construct source level debugging information.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SUPPORT_DEBUGINFOBUILDER_H
+#define LLVM_SUPPORT_DEBUGINFOBUILDER_H
+
+#include <llvm/Module.h>
+#include <string>
+
+namespace llvm {
+    
+class Type;
+class IntegerType;
+class FloatType;
+class StructType;
+class PointerType;
+class Module;
+class GlobalVariable;
+class Constant;
+
+namespace sys {
+    class Path;
+}
+
+/// Helper class used to construct source-level debugging information.
+///
+/// The helper contains a notion of "current context", which is a
+/// DWARF descriptor object representing the scope (module, class,
+/// function, etc.) that currently encloses the definitions being
+/// emitted.
+///
+/// Initially, you should call setModule() to specify the target
+/// module. Descriptors which are generated will be inserted into
+/// this module. This also generates the initial set of anchor
+/// descriptors, if they have not already been created for the module.
+///
+/// Next, you should call createCompileUnitDescriptor() to create
+/// the descriptor for the current compilation unit. This method
+/// sets the current context to the newly created descriptor.
+///
+/// Once that has been done, you can then create descriptors for
+/// global definitions (functions, variables, etc.). You can use
+/// setContext() to modify the current context. setContext() returns
+/// a reference to the previous context, allowing easy restoration
+/// of the previous context.
+class DebugInfoBuilder {
+private:
+    Module * module;
+    PointerType * anyPtrType;    // Pointer to empty struct
+    StructType * anchorType;
+    GlobalVariable * compileUnit;
+    GlobalVariable * context;
+    GlobalVariable * compileUnitAnchor;
+    GlobalVariable * globalVariableAnchor;
+    GlobalVariable * subprogramAnchor;
+    GlobalVariable * compileUnitDescriptor;
+
+    // Create an anchor with the specified tag.
+    GlobalVariable * createAnchor(unsigned anchorTag, const char * anchorName);
+
+    // Calculate alignement for primitive types.
+    unsigned getBasicAlignment(unsigned sizeInBits);
+
+    // Calculate the size of the specified LLVM type.
+    Constant * getSize(const Type * type);
+
+    // Calculate the alignment of the specified LLVM type.
+    Constant * getAlignment(const Type * type);
+
+public:
+    /// Constructor
+    DebugInfoBuilder();
+
+    /// Return the type defined by llvm.dbg.anchor.type
+    StructType * getAnchorType() const { return anchorType; }
+    
+    /// Set the reference to the module where we will insert debugging
+    /// information. Also defines the debug info types for the module and
+    /// creates the initial anchors. Also changes the current context to the
+    // global context for that module.
+    void setModule(Module * m);
+    
+    /// Emit a compile unit descriptor. This should be done once for each
+    /// module before any other debug descriptors are created. This also
+    /// changes the current context to the global context for the compile unit.
+    GlobalVariable * createCompileUnitDescriptor(
+        unsigned langId,
+        const sys::Path & srcPath,
+        const std::string & producer);
+
+    /// Set a new context, returning the previous context. The context is the
+    /// debug descriptor representing the current scope (module, function,
+    /// class, etc.)
+    GlobalVariable * setContext(GlobalVariable * ctx) {
+        GlobalVariable * prev = context;
+        context = ctx;
+        return prev;
+    }
+    
+    /// Emit a subprogram descriptor in the current context.
+    GlobalVariable * createSubProgramDescriptor(
+        const std::string & name,       // Name of the subprogram
+        const std::string & qualName,   // Fully-qualified name
+        unsigned line,                  // Line number
+        GlobalVariable * typeDesc,      // Type descriptor
+        bool isInternalScoped,          // True if internal to module.
+        bool isDefined);                // True if defined in this module.
+
+    /// Create a type descriptor for a primitive type.
+    GlobalVariable * createBasicTypeDescriptor(
+        std::string & name,
+        unsigned line,
+        unsigned sizeInBits,
+        unsigned alignmentInBits,
+        unsigned offsetInBits,
+        unsigned typeEncoding);
+
+    /// Create a type descriptor for an integer type
+    GlobalVariable * createIntegerTypeDescriptor(
+        std::string & name, const IntegerType * type, bool isSigned);
+
+    /// Create a type descriptor for an character type
+    GlobalVariable * createCharacterTypeDescriptor(
+        std::string & name, const IntegerType * type, bool isSigned);
+
+    /// Create a type descriptor for an floating-point type
+    GlobalVariable * createFloatTypeDescriptor(std::string & name,
+        const Type * type);
+
+    /// Create a type descriptor for a pointer type.
+    GlobalVariable * createPointerTypeDescriptor(
+        std::string & name,             // Name of the type
+        GlobalVariable * referenceType, // Descriptor for what is pointed to
+        const PointerType * type,       // LLVM type of the pointer
+        unsigned line);                 // Line number of definition (0 if none)
+};
+
+}
+
+#endif
diff --git a/lib/VMCore/DebugInfoBuilder.cpp b/lib/VMCore/DebugInfoBuilder.cpp
new file mode 100644
index 0000000000..c3eba771d0
--- /dev/null
+++ b/lib/VMCore/DebugInfoBuilder.cpp
@@ -0,0 +1,272 @@
+//===-- llvm/VMCore/DebugInfoBuilder.cpp - ----------------------*- C++ -*-===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+//
+// This file contains the definition of the DebugInfoBuilder class, which is
+// a helper class used to construct source level debugging information.
+//
+//===----------------------------------------------------------------------===//
+
+#include <llvm/Support/DebugInfoBuilder.h>
+#include <llvm/DerivedTypes.h>
+#include <llvm/Constants.h>
+#include <llvm/GlobalVariable.h>
+#include <llvm/Module.h>
+#include <llvm/Support/Dwarf.h>
+#include <llvm/System/Path.h>
+
+namespace llvm {
+    
+//===----------------------------------------------------------------------===//
+// Debug version -- copied from MachineModuleInfo (for now), in order to avoid
+// creating a dependency on CodeGen. These declarations really should be moved
+// to a better place where modules can get at them without being dependent on
+// CodeGen.
+enum {
+  LLVMDebugVersion = (6 << 16),         // Current version of debug information.
+  LLVMDebugVersion5 = (5 << 16),        // Constant for version 5.
+  LLVMDebugVersion4 = (4 << 16),        // Constant for version 4.
+  LLVMDebugVersionMask = 0xffff0000     // Mask for version number.
+};
+
+const char ANCHOR_TYPE_NAME[] = "llvm.dbg.anchor.type";
+const char COMPILE_UNIT_ANCHOR_NAME[] = "llvm.dbg.compile_units";
+const char GLOBAL_VAR_ANCHOR_NAME[] = "llvm.dbg.global_variables";
+const char SUBPROGRAM_ANCHOR_NAME[] = "llvm.dbg.subprograms";
+const char COMPILE_UNIT_TYPE_NAME[] = "llvm.dbg.compile_unit.type";
+const char COMPILE_UNIT_NAME[] = "llvm.dbg.compile_unit";
+const char SUBPROGRAM_NAME[] = "llvm.dbg.subprogram";
+const char BASICTYPE_NAME[] = "llvm.dbg.basictype";
+const char DERIVEDTYPE_NAME[] = "llvm.dbg.derivedtype";
+
+DebugInfoBuilder::DebugInfoBuilder() {
+    anyPtrType = PointerType::getUnqual(StructType::get(NULL, NULL));
+    anchorType = StructType::get(Type::Int32Ty, Type::Int32Ty, NULL);
+}
+
+GlobalVariable * DebugInfoBuilder::createAnchor(unsigned anchorTag,
+    const char * anchorName) {
+
+    std::vector<Constant *> values;
+    values.push_back(ConstantInt::get(Type::Int32Ty, LLVMDebugVersion));
+    values.push_back(ConstantInt::get(Type::Int32Ty, anchorTag));
+    
+    return new GlobalVariable(anchorType, true, GlobalValue::LinkOnceLinkage,
+        ConstantStruct::get(anchorType, values), anchorName, module);
+}
+
+// Calculate the size of the specified LLVM type.
+Constant * DebugInfoBuilder::getSize(const Type * type) {
+    Constant * one = ConstantInt::get(Type::Int32Ty, 1);
+    return ConstantExpr::getPtrToInt(
+        ConstantExpr::getGetElementPtr(
+            ConstantPointerNull::get(PointerType::getUnqual(type)),
+            &one, 1), Type::Int32Ty);
+}
+    
+Constant * DebugInfoBuilder::getAlignment(const Type * type) {
+    // Calculates the alignment of T using "sizeof({i8, T}) - sizeof(T)"
+    return ConstantExpr::getSub(
+        getSize(StructType::get(Type::Int8Ty, type, NULL)),
+        getSize(type));
+}
+    
+void DebugInfoBuilder::setModule(Module * m) {
+    module = m;
+    module->addTypeName(ANCHOR_TYPE_NAME, anchorType);
+    
+    compileUnitAnchor = module->getGlobalVariable(COMPILE_UNIT_ANCHOR_NAME);
+    if (compileUnitAnchor == NULL) {
+        compileUnitAnchor =
+            createAnchor(dwarf::DW_TAG_compile_unit, COMPILE_UNIT_ANCHOR_NAME);
+    }
+
+    globalVariableAnchor = module->getGlobalVariable(GLOBAL_VAR_ANCHOR_NAME);
+    if (globalVariableAnchor == NULL) {
+        globalVariableAnchor =
+            createAnchor(dwarf::DW_TAG_compile_unit, GLOBAL_VAR_ANCHOR_NAME);
+    }
+
+    subprogramAnchor = module->getGlobalVariable(SUBPROGRAM_ANCHOR_NAME);
+    if (subprogramAnchor == NULL) {
+        subprogramAnchor =
+            createAnchor(dwarf::DW_TAG_compile_unit, SUBPROGRAM_ANCHOR_NAME);
+    }
+    
+    compileUnit = module->getGlobalVariable(COMPILE_UNIT_NAME);
+    setContext(compileUnit);
+}
+    
+GlobalVariable * DebugInfoBuilder::createCompileUnitDescriptor(unsigned langId,
+    const sys::Path & srcPath, const std::string & producer) {
+
+    if (compileUnit == NULL) {
+        std::vector<Constant *> values;
+        values.push_back(ConstantInt::get(
+            Type::Int32Ty, LLVMDebugVersion + dwarf::DW_TAG_compile_unit));
+        values.push_back(
+            ConstantExpr::getBitCast(compileUnitAnchor, anyPtrType));
+        values.push_back(ConstantInt::get(Type::Int32Ty, langId));
+        values.push_back(ConstantArray::get(srcPath.getLast()));
+        values.push_back(ConstantArray::get(srcPath.getDirname() + "/"));
+        values.push_back(ConstantArray::get(producer));
+    
+        Constant * structVal = ConstantStruct::get(values, false);
+        compileUnit = new GlobalVariable(structVal->getType(), true,
+            GlobalValue::InternalLinkage, structVal, COMPILE_UNIT_NAME, module);
+    }
+
+    setContext(compileUnit);
+    return compileUnit;
+}
+
+GlobalVariable * DebugInfoBuilder::createSubProgramDescriptor(
+    const std::string & name,
+    const std::string & qualifiedName,
+    unsigned line,
+    GlobalVariable * typeDesc,
+    bool isInternal,
+    bool isDefined) {
+        
+    assert(compileUnit != NULL);
+    assert(subprogramAnchor != NULL);
+        
+    std::vector<Constant *> values;
+    values.push_back(ConstantInt::get(
+        Type::Int32Ty, LLVMDebugVersion + dwarf::DW_TAG_subprogram));
+    values.push_back(ConstantExpr::getBitCast(subprogramAnchor, anyPtrType));
+    values.push_back(ConstantExpr::getBitCast(context, anyPtrType));
+    values.push_back(ConstantArray::get(name));
+    values.push_back(ConstantArray::get(qualifiedName));
+    values.push_back(ConstantArray::get(qualifiedName));
+    values.push_back(ConstantExpr::getBitCast(compileUnit, anyPtrType));
+    values.push_back(ConstantInt::get(Type::Int32Ty, line));
+    values.push_back(typeDesc ?
+        ConstantExpr::getBitCast(typeDesc, anyPtrType) :
+        ConstantPointerNull::get(anyPtrType));
+    values.push_back(ConstantInt::get(Type::Int1Ty, isInternal));
+    values.push_back(ConstantInt::get(Type::Int1Ty, isDefined));
+    
+    Constant * structVal = ConstantStruct::get(values, false);
+    return new GlobalVariable(structVal->getType(), true,
+        GlobalValue::InternalLinkage, structVal, SUBPROGRAM_NAME, module);
+}
+
+GlobalVariable * DebugInfoBuilder::createBasicTypeDescriptor(
+    std::string & name,
+    unsigned line,
+    unsigned sizeInBits,
+    unsigned alignmentInBits,
+    unsigned offsetInBits,
+    unsigned typeEncoding) {
+
+    std::vector<Constant *> values;
+    values.push_back(ConstantInt::get(
+        Type::Int32Ty, LLVMDebugVersion + dwarf::DW_TAG_base_type));
+    values.push_back(ConstantExpr::getBitCast(context, anyPtrType));
+    values.push_back(ConstantArray::get(name));
+    values.push_back(ConstantExpr::getBitCast(compileUnit, anyPtrType));
+    values.push_back(ConstantInt::get(Type::Int32Ty, line));
+    values.push_back(ConstantInt::get(Type::Int32Ty, sizeInBits));
+    values.push_back(ConstantInt::get(Type::Int32Ty, alignmentInBits));
+    values.push_back(ConstantInt::get(Type::Int32Ty, offsetInBits));
+    values.push_back(ConstantInt::get(Type::Int32Ty, typeEncoding));
+
+    Constant * structVal = ConstantStruct::get(values, false);
+    return new GlobalVariable(structVal->getType(), true,
+        GlobalValue::InternalLinkage, structVal, BASICTYPE_NAME, module);
+}
+
+GlobalVariable * DebugInfoBuilder::createIntegerTypeDescriptor(
+    std::string & name, const IntegerType * type, bool isSigned) {
+
+    std::vector<Constant *> values;
+    values.push_back(ConstantInt::get(
+        Type::Int32Ty, LLVMDebugVersion + dwarf::DW_TAG_base_type));
+    values.push_back(ConstantPointerNull::get(anyPtrType));
+    values.push_back(ConstantArray::get(name));
+    values.push_back(ConstantPointerNull::get(anyPtrType));
+    values.push_back(ConstantInt::get(Type::Int32Ty, 0));
+    values.push_back(ConstantInt::get(Type::Int32Ty, type->getBitWidth()));
+    values.push_back(getAlignment(type));
+    values.push_back(ConstantInt::get(Type::Int32Ty, 0));
+    values.push_back(ConstantInt::get(Type::Int32Ty,
+        isSigned ? dwarf::DW_ATE_signed_char : dwarf::DW_ATE_unsigned_char));
+
+    Constant * structVal = ConstantStruct::get(values, false);
+    return new GlobalVariable(structVal->getType(), true,
+        GlobalValue::InternalLinkage, structVal, BASICTYPE_NAME, module);
+}
+
+GlobalVariable * DebugInfoBuilder::createCharacterTypeDescriptor(
+    std::string & name, const IntegerType * type, bool isSigned) {
+
+    std::vector<Constant *> values;
+    values.push_back(ConstantInt::get(
+        Type::Int32Ty, LLVMDebugVersion + dwarf::DW_TAG_base_type));
+    values.push_back(ConstantPointerNull::get(anyPtrType));
+    values.push_back(ConstantArray::get(name));
+    values.push_back(ConstantPointerNull::get(anyPtrType));
+    values.push_back(ConstantInt::get(Type::Int32Ty, 0));
+    values.push_back(ConstantInt::get(Type::Int32Ty, type->getBitWidth()));
+    values.push_back(getAlignment(type));
+    values.push_back(ConstantInt::get(Type::Int32Ty, 0/*offsetInBits*/));
+    values.push_back(ConstantInt::get(Type::Int32Ty,
+        isSigned ? dwarf::DW_ATE_signed_char : dwarf::DW_ATE_unsigned_char));
+
+    Constant * structVal = ConstantStruct::get(values, false);
+    return new GlobalVariable(structVal->getType(), true,
+        GlobalValue::InternalLinkage, structVal, BASICTYPE_NAME, module);
+}
+
+GlobalVariable * DebugInfoBuilder::createFloatTypeDescriptor(
+    std::string & name, const Type * type) {
+
+    std::vector<Constant *> values;
+    values.push_back(ConstantInt::get(
+        Type::Int32Ty, LLVMDebugVersion + dwarf::DW_TAG_base_type));
+    values.push_back(ConstantPointerNull::get(anyPtrType));
+    values.push_back(ConstantArray::get(name));
+    values.push_back(ConstantPointerNull::get(anyPtrType));
+    values.push_back(ConstantInt::get(Type::Int32Ty, 0));
+    values.push_back(getSize(type));
+    values.push_back(getAlignment(type));
+    values.push_back(ConstantInt::get(Type::Int32Ty, 0/*offsetInBits*/));
+    values.push_back(ConstantInt::get(Type::Int32Ty, dwarf::DW_ATE_float));
+
+    Constant * structVal = ConstantStruct::get(values, false);
+    return new GlobalVariable(structVal->getType(), true,
+        GlobalValue::InternalLinkage, structVal, BASICTYPE_NAME, module);
+}
+
+GlobalVariable * DebugInfoBuilder::createPointerTypeDescriptor(
+    std::string & name,
+    GlobalVariable * referenceType,
+    const PointerType * type,
+    unsigned line) {
+
+    std::vector<Constant *> values;
+    values.push_back(ConstantInt::get(
+        Type::Int32Ty, dwarf::DW_TAG_pointer_type + LLVMDebugVersion));
+    values.push_back(
+        context ? ConstantExpr::getBitCast(context, anyPtrType) : NULL);
+    values.push_back(ConstantArray::get(name));
+    values.push_back(
+        compileUnit ? ConstantExpr::getBitCast(compileUnit, anyPtrType) : NULL);
+    values.push_back(ConstantInt::get(Type::Int32Ty, line));
+    values.push_back(getSize(type));
+    values.push_back(getAlignment(type));
+    values.push_back(ConstantInt::get(Type::Int32Ty, 0));
+    values.push_back(referenceType);
+
+    Constant * structVal = ConstantStruct::get(values, false);
+    return new GlobalVariable(structVal->getType(), true,
+        GlobalValue::InternalLinkage, structVal, DERIVEDTYPE_NAME, module);
+}
+
+}