forked from OSchip/llvm-project
				
			
		
			
				
	
	
		
			2031 lines
		
	
	
		
			72 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			2031 lines
		
	
	
		
			72 KiB
		
	
	
	
		
			C++
		
	
	
	
//===-- examples/ExceptionDemo/ExceptionDemo.cpp - 
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//                      An example use of the llvm Exception mechanism --===//
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//
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//                     The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===--------------------------------------------------------------------===//
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//
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// Demo program which implements an example LLVM exception implementation, and
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// shows several test cases including the handling of foreign exceptions.
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// It is run with type info types arguments to throw. A test will
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// be run for each given type info type. While type info types with the value 
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// of -1 will trigger a foreign C++ exception to be thrown; type info types
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// <= 6 and >= 1 will cause the associated generated exceptions to be thrown 
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// and caught by generated test functions; and type info types > 6
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// will result in exceptions which pass through to the test harness. All other
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// type info types are not supported and could cause a crash. In all cases,
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// the "finally" blocks of every generated test functions will executed 
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// regardless of whether or not that test function ignores or catches the
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// thrown exception.
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//
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// examples:
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//
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// ExceptionDemo
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//
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//     causes a usage to be printed to stderr
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// 
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// ExceptionDemo 2 3 7 -1
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//
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//     results in the following cases:
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//         - Value 2 causes an exception with a type info type of 2 to be 
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//           thrown and caught by an inner generated test function.
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//         - Value 3 causes an exception with a type info type of 3 to be 
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//           thrown and caught by an outer generated test function.
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//         - Value 7 causes an exception with a type info type of 7 to be 
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//           thrown and NOT be caught by any generated function.
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//         - Value -1 causes a foreign C++ exception to be thrown and not be
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//           caught by any generated function
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//
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//     Cases -1 and 7 are caught by a C++ test harness where the validity of
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//         of a C++ catch(...) clause catching a generated exception with a 
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//         type info type of 7 is questionable.
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//
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// This code uses code from the llvm compiler-rt project and the llvm 
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// Kaleidoscope project.
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//
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//===--------------------------------------------------------------------===//
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#include "llvm/LLVMContext.h"
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#include "llvm/DerivedTypes.h"
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#include "llvm/ExecutionEngine/ExecutionEngine.h"
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#include "llvm/ExecutionEngine/JIT.h"
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#include "llvm/Module.h"
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#include "llvm/PassManager.h"
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#include "llvm/Intrinsics.h"
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#include "llvm/Analysis/Verifier.h"
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#include "llvm/Target/TargetData.h"
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#include "llvm/Target/TargetSelect.h"
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#include "llvm/Target/TargetOptions.h"
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#include "llvm/Transforms/Scalar.h"
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#include "llvm/Support/IRBuilder.h"
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#include "llvm/Support/Dwarf.h"
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#include <cstdio>
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#include <string>
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#include <sstream>
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#include <map>
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#include <vector>
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#include <stdexcept>
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#ifndef USE_GLOBAL_STR_CONSTS
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#define USE_GLOBAL_STR_CONSTS true
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#endif
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// System C++ ABI unwind types from: 
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//     http://refspecs.freestandards.org/abi-eh-1.21.html
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extern "C" {
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typedef enum {
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    _URC_NO_REASON = 0,
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    _URC_FOREIGN_EXCEPTION_CAUGHT = 1,
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    _URC_FATAL_PHASE2_ERROR = 2,
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    _URC_FATAL_PHASE1_ERROR = 3,
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    _URC_NORMAL_STOP = 4,
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    _URC_END_OF_STACK = 5,
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    _URC_HANDLER_FOUND = 6,
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    _URC_INSTALL_CONTEXT = 7,
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    _URC_CONTINUE_UNWIND = 8
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} _Unwind_Reason_Code;
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typedef enum {
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    _UA_SEARCH_PHASE = 1,
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    _UA_CLEANUP_PHASE = 2,
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    _UA_HANDLER_FRAME = 4,
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    _UA_FORCE_UNWIND = 8,
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    _UA_END_OF_STACK = 16
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} _Unwind_Action;
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struct _Unwind_Exception;
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typedef void (*_Unwind_Exception_Cleanup_Fn) (_Unwind_Reason_Code,
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                                              struct _Unwind_Exception *);
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struct _Unwind_Exception {
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    uint64_t exception_class;
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    _Unwind_Exception_Cleanup_Fn exception_cleanup;
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    uintptr_t private_1;    
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    uintptr_t private_2;    
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    // @@@ The IA-64 ABI says that this structure must be double-word aligned.
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    //  Taking that literally does not make much sense generically.  Instead 
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    //  we provide the maximum alignment required by any type for the machine.
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} __attribute__((__aligned__));
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struct _Unwind_Context;
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typedef struct _Unwind_Context* _Unwind_Context_t;
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extern const uint8_t* _Unwind_GetLanguageSpecificData (_Unwind_Context_t c);
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extern uintptr_t _Unwind_GetGR (_Unwind_Context_t c, int i);
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extern void _Unwind_SetGR (_Unwind_Context_t c, int i, uintptr_t n);
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extern void _Unwind_SetIP (_Unwind_Context_t, uintptr_t new_value);
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extern uintptr_t _Unwind_GetIP (_Unwind_Context_t context);
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extern uintptr_t _Unwind_GetRegionStart (_Unwind_Context_t context);
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} // extern "C"
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//
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// Example types
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//
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/// This is our simplistic type info
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struct OurExceptionType_t {
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    /// type info type
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    int type;
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};
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/// This is our Exception class which relies on a negative offset to calculate
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/// pointers to its instances from pointers to its unwindException member.
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/// 
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/// Note: The above unwind.h defines struct _Unwind_Exception to be aligned
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///       on a double word boundary. This is necessary to match the standard:
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///       http://refspecs.freestandards.org/abi-eh-1.21.html
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struct OurBaseException_t {
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    struct OurExceptionType_t type;
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    // Note: This is properly aligned in unwind.h
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    struct _Unwind_Exception unwindException;
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};
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// Note: Not needed since we are C++
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typedef struct OurBaseException_t OurException;
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typedef struct _Unwind_Exception OurUnwindException;
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//
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// Various globals used to support typeinfo and generatted exceptions in 
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// general
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//
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static std::map<std::string, llvm::Value*> namedValues;
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int64_t ourBaseFromUnwindOffset;
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const unsigned char ourBaseExcpClassChars[] = 
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                                {'o', 'b', 'j', '\0', 'b', 'a', 's', '\0'};
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static uint64_t ourBaseExceptionClass = 0;
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static std::vector<std::string> ourTypeInfoNames;
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static std::map<int, std::string> ourTypeInfoNamesIndex;
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static llvm::StructType* ourTypeInfoType;
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static llvm::StructType* ourExceptionType;
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static llvm::StructType* ourUnwindExceptionType;
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static llvm::ConstantInt* ourExceptionNotThrownState;
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static llvm::ConstantInt* ourExceptionThrownState;
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static llvm::ConstantInt* ourExceptionCaughtState;
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typedef std::vector<std::string> ArgNames;
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typedef std::vector<const llvm::Type*> ArgTypes;
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//
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// Code Generation Utilities
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//
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/// Utility used to create a function, both declarations and definitions
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/// @param module for module instance
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/// @param retType function return type
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/// @param theArgTypes function's ordered argument types
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/// @param theArgNames function's ordered arguments needed if use of this
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///        function corresponds to a function definition. Use empty 
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///        aggregate for function declarations.
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/// @param functName function name
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/// @param linkage function linkage
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/// @param declarationOnly for function declarations
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/// @param isVarArg function uses vararg arguments
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/// @returns function instance
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llvm::Function *createFunction(llvm::Module& module,
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                               const llvm::Type* retType,
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                               const ArgTypes& theArgTypes,
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                               const ArgNames& theArgNames,
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                               const std::string& functName,
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                               llvm::GlobalValue::LinkageTypes linkage,
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                               bool declarationOnly,
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                               bool isVarArg) {
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    llvm::FunctionType* functType = llvm::FunctionType::get(retType, 
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                                                            theArgTypes, 
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                                                            isVarArg);
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    llvm::Function* ret = llvm::Function::Create(functType, 
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                                                 linkage, 
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                                                 functName, 
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                                                 &module);
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						|
    if (!ret || declarationOnly)
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        return(ret);
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    namedValues.clear();
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    unsigned i = 0; 
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    for (llvm::Function::arg_iterator argIndex = ret->arg_begin();
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         i != theArgNames.size();
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         ++argIndex, ++i) {
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        argIndex->setName(theArgNames[i]);
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        namedValues[theArgNames[i]] = argIndex;
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    }
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    return(ret);
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}
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/// Create an alloca instruction in the entry block of
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/// the parent function.  This is used for mutable variables etc.
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/// @param function parent instance
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/// @param varName stack variable name
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/// @param type stack variable type
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/// @param initWith optional constant initialization value
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/// @returns AllocaInst instance
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static llvm::AllocaInst *createEntryBlockAlloca(llvm::Function& function,
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                                            const std::string &varName,
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                                            const llvm::Type* type,
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                                            llvm::Constant* initWith = NULL) {
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    llvm::BasicBlock& block = function.getEntryBlock(); 
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    llvm::IRBuilder<> tmp(&block, block.begin());
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    llvm::AllocaInst* ret = tmp.CreateAlloca(type, 0, varName.c_str());
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    if (initWith) 
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        tmp.CreateStore(initWith, ret);
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    return(ret);
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}
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//
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// Code Generation Utilities End
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//
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//
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// Runtime C Library functions 
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//
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// Note: using an extern "C" block so that static functions can be used
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extern "C" {
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// Note: Better ways to decide on bit width
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//
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/// Prints a 32 bit number, according to the format, to stderr.
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/// @param intToPrint integer to print 
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/// @param format printf like format to use when printing
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void print32Int(int intToPrint, const char* format) {
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						|
    if (format) {
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        // Note: No NULL check
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        fprintf(stderr, format, intToPrint);
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						|
    }
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						|
    else {
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						|
        // Note: No NULL check
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						|
        fprintf(stderr, "::print32Int(...):NULL arg.\n");
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    }
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						|
}
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						|
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						|
// Note: Better ways to decide on bit width
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						|
//
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						|
/// Prints a 64 bit number, according to the format, to stderr.
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						|
/// @param intToPrint integer to print 
 | 
						|
/// @param format printf like format to use when printing
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						|
void print64Int(long int intToPrint, const char* format) {
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						|
    if (format) {
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						|
        // Note: No NULL check
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						|
        fprintf(stderr, format, intToPrint);
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						|
    }
 | 
						|
    else {
 | 
						|
        // Note: No NULL check
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						|
        fprintf(stderr, "::print64Int(...):NULL arg.\n");
 | 
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    }
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						|
}
 | 
						|
 | 
						|
 | 
						|
/// Prints a C string to stderr
 | 
						|
/// @param toPrint string to print
 | 
						|
void printStr(char* toPrint) {
 | 
						|
    if (toPrint) {
 | 
						|
        fprintf(stderr, "%s", toPrint);
 | 
						|
    }
 | 
						|
    else {
 | 
						|
        fprintf(stderr, "::printStr(...):NULL arg.\n");
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Deletes the true previosly allocated exception whose address
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						|
/// is calculated from the supplied OurBaseException_t::unwindException
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						|
/// member address. Handles (ignores), NULL pointers.
 | 
						|
/// @param expToDelete exception to delete
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						|
void deleteOurException(OurUnwindException* expToDelete) {
 | 
						|
#ifdef DEBUG
 | 
						|
    fprintf(stderr,
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            "deleteOurException(...).\n");
 | 
						|
#endif
 | 
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 | 
						|
    if (expToDelete &&
 | 
						|
        (expToDelete->exception_class == ourBaseExceptionClass)) {
 | 
						|
 | 
						|
        free(((char*) expToDelete) + ourBaseFromUnwindOffset);
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// This function is the struct _Unwind_Exception API mandated delete function 
 | 
						|
/// used by foreign exception handlers when deleting our exception 
 | 
						|
/// (OurException), instances.
 | 
						|
/// @param reason @link http://refspecs.freestandards.org/abi-eh-1.21.html 
 | 
						|
/// @unlink
 | 
						|
/// @param expToDelete exception instance to delete
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						|
void deleteFromUnwindOurException(_Unwind_Reason_Code reason,
 | 
						|
                                  OurUnwindException* expToDelete) {
 | 
						|
#ifdef DEBUG
 | 
						|
    fprintf(stderr,
 | 
						|
            "deleteFromUnwindOurException(...).\n");
 | 
						|
#endif
 | 
						|
 | 
						|
    deleteOurException(expToDelete);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Creates (allocates on the heap), an exception (OurException instance),
 | 
						|
/// of the supplied type info type.
 | 
						|
/// @param type type info type
 | 
						|
OurUnwindException* createOurException(int type) {
 | 
						|
    size_t size = sizeof(OurException);
 | 
						|
    OurException* ret = (OurException*) memset(malloc(size), 0, size);
 | 
						|
    (ret->type).type = type;
 | 
						|
    (ret->unwindException).exception_class = ourBaseExceptionClass;
 | 
						|
    (ret->unwindException).exception_cleanup = deleteFromUnwindOurException;
 | 
						|
 | 
						|
    return(&(ret->unwindException));
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Read a uleb128 encoded value and advance pointer 
 | 
						|
/// See Variable Length Data in: 
 | 
						|
/// @link http://dwarfstd.org/Dwarf3.pdf @unlink
 | 
						|
/// @param data reference variable holding memory pointer to decode from
 | 
						|
/// @returns decoded value
 | 
						|
static uintptr_t readULEB128(const uint8_t** data) {
 | 
						|
    uintptr_t result = 0;
 | 
						|
    uintptr_t shift = 0;
 | 
						|
    unsigned char byte;
 | 
						|
    const uint8_t* p = *data;
 | 
						|
 | 
						|
    do {
 | 
						|
        byte = *p++;
 | 
						|
        result |= (byte & 0x7f) << shift;
 | 
						|
        shift += 7;
 | 
						|
    } 
 | 
						|
    while (byte & 0x80);
 | 
						|
 | 
						|
    *data = p;
 | 
						|
 | 
						|
    return result;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Read a sleb128 encoded value and advance pointer 
 | 
						|
/// See Variable Length Data in: 
 | 
						|
/// @link http://dwarfstd.org/Dwarf3.pdf @unlink
 | 
						|
/// @param data reference variable holding memory pointer to decode from
 | 
						|
/// @returns decoded value
 | 
						|
static uintptr_t readSLEB128(const uint8_t** data) {
 | 
						|
    uintptr_t result = 0;
 | 
						|
    uintptr_t shift = 0;
 | 
						|
    unsigned char byte;
 | 
						|
    const uint8_t* p = *data;
 | 
						|
 | 
						|
    do {
 | 
						|
        byte = *p++;
 | 
						|
        result |= (byte & 0x7f) << shift;
 | 
						|
        shift += 7;
 | 
						|
    } 
 | 
						|
    while (byte & 0x80);
 | 
						|
 | 
						|
    *data = p;
 | 
						|
 | 
						|
    if ((byte & 0x40) && (shift < (sizeof(result) << 3))) {
 | 
						|
        result |= (~0 << shift);
 | 
						|
    }
 | 
						|
 | 
						|
    return result;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Read a pointer encoded value and advance pointer 
 | 
						|
/// See Variable Length Data in: 
 | 
						|
/// @link http://dwarfstd.org/Dwarf3.pdf @unlink
 | 
						|
/// @param data reference variable holding memory pointer to decode from
 | 
						|
/// @param encoding dwarf encoding type
 | 
						|
/// @returns decoded value
 | 
						|
static uintptr_t readEncodedPointer(const uint8_t** data, uint8_t encoding) {
 | 
						|
    uintptr_t result = 0;
 | 
						|
    const uint8_t* p = *data;
 | 
						|
 | 
						|
    if (encoding == llvm::dwarf::DW_EH_PE_omit) 
 | 
						|
        return(result);
 | 
						|
 | 
						|
    // first get value 
 | 
						|
    switch (encoding & 0x0F) {
 | 
						|
        case llvm::dwarf::DW_EH_PE_absptr:
 | 
						|
            result = *((uintptr_t*)p);
 | 
						|
            p += sizeof(uintptr_t);
 | 
						|
            break;
 | 
						|
        case llvm::dwarf::DW_EH_PE_uleb128:
 | 
						|
            result = readULEB128(&p);
 | 
						|
            break;
 | 
						|
        // Note: This case has not been tested
 | 
						|
        case llvm::dwarf::DW_EH_PE_sleb128:
 | 
						|
            result = readSLEB128(&p);
 | 
						|
            break;
 | 
						|
        case llvm::dwarf::DW_EH_PE_udata2:
 | 
						|
            result = *((uint16_t*)p);
 | 
						|
            p += sizeof(uint16_t);
 | 
						|
            break;
 | 
						|
        case llvm::dwarf::DW_EH_PE_udata4:
 | 
						|
            result = *((uint32_t*)p);
 | 
						|
            p += sizeof(uint32_t);
 | 
						|
            break;
 | 
						|
        case llvm::dwarf::DW_EH_PE_udata8:
 | 
						|
            result = *((uint64_t*)p);
 | 
						|
            p += sizeof(uint64_t);
 | 
						|
            break;
 | 
						|
        case llvm::dwarf::DW_EH_PE_sdata2:
 | 
						|
            result = *((int16_t*)p);
 | 
						|
            p += sizeof(int16_t);
 | 
						|
            break;
 | 
						|
        case llvm::dwarf::DW_EH_PE_sdata4:
 | 
						|
            result = *((int32_t*)p);
 | 
						|
            p += sizeof(int32_t);
 | 
						|
            break;
 | 
						|
        case llvm::dwarf::DW_EH_PE_sdata8:
 | 
						|
            result = *((int64_t*)p);
 | 
						|
            p += sizeof(int64_t);
 | 
						|
            break;
 | 
						|
        default:
 | 
						|
            // not supported 
 | 
						|
            abort();
 | 
						|
            break;
 | 
						|
    }
 | 
						|
 | 
						|
    // then add relative offset 
 | 
						|
    switch (encoding & 0x70) {
 | 
						|
        case llvm::dwarf::DW_EH_PE_absptr:
 | 
						|
            // do nothing 
 | 
						|
            break;
 | 
						|
        case llvm::dwarf::DW_EH_PE_pcrel:
 | 
						|
            result += (uintptr_t)(*data);
 | 
						|
            break;
 | 
						|
        case llvm::dwarf::DW_EH_PE_textrel:
 | 
						|
        case llvm::dwarf::DW_EH_PE_datarel:
 | 
						|
        case llvm::dwarf::DW_EH_PE_funcrel:
 | 
						|
        case llvm::dwarf::DW_EH_PE_aligned:
 | 
						|
        default:
 | 
						|
            // not supported 
 | 
						|
            abort();
 | 
						|
            break;
 | 
						|
    }
 | 
						|
 | 
						|
    // then apply indirection 
 | 
						|
    if (encoding & llvm::dwarf::DW_EH_PE_indirect) {
 | 
						|
        result = *((uintptr_t*)result);
 | 
						|
    }
 | 
						|
 | 
						|
    *data = p;
 | 
						|
 | 
						|
    return result;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Deals with Dwarf actions matching our type infos 
 | 
						|
/// (OurExceptionType_t instances). Returns whether or not a dwarf emitted 
 | 
						|
/// action matches the supplied exception type. If such a match succeeds, 
 | 
						|
/// the resultAction argument will be set with > 0 index value. Only 
 | 
						|
/// corresponding llvm.eh.selector type info arguments, cleanup arguments 
 | 
						|
/// are supported. Filters are not supported.
 | 
						|
/// See Variable Length Data in: 
 | 
						|
/// @link http://dwarfstd.org/Dwarf3.pdf @unlink
 | 
						|
/// Also see @link http://refspecs.freestandards.org/abi-eh-1.21.html @unlink
 | 
						|
/// @param resultAction reference variable which will be set with result
 | 
						|
/// @param classInfo our array of type info pointers (to globals)
 | 
						|
/// @param actionEntry index into above type info array or 0 (clean up). 
 | 
						|
///        We do not support filters.
 | 
						|
/// @param exceptionClass exception class (_Unwind_Exception::exception_class)
 | 
						|
///        of thrown exception.
 | 
						|
/// @param exceptionObject thrown _Unwind_Exception instance.
 | 
						|
/// @returns whether or not a type info was found. False is returned if only
 | 
						|
///          a cleanup was found
 | 
						|
static bool handleActionValue(int64_t *resultAction,
 | 
						|
                              struct OurExceptionType_t **classInfo, 
 | 
						|
                              uintptr_t actionEntry, 
 | 
						|
                              uint64_t exceptionClass, 
 | 
						|
                              struct _Unwind_Exception *exceptionObject) {
 | 
						|
    bool ret = false;
 | 
						|
 | 
						|
    if (!resultAction || 
 | 
						|
        !exceptionObject || 
 | 
						|
        (exceptionClass != ourBaseExceptionClass))
 | 
						|
        return(ret);
 | 
						|
 | 
						|
    struct OurBaseException_t* excp = (struct OurBaseException_t*)
 | 
						|
                        (((char*) exceptionObject) + ourBaseFromUnwindOffset);
 | 
						|
    struct OurExceptionType_t *excpType = &(excp->type);
 | 
						|
    int type = excpType->type;
 | 
						|
 | 
						|
#ifdef DEBUG
 | 
						|
    fprintf(stderr,
 | 
						|
            "handleActionValue(...): exceptionObject = <%p>, "
 | 
						|
                "excp = <%p>.\n",
 | 
						|
            exceptionObject,
 | 
						|
            excp);
 | 
						|
#endif
 | 
						|
 | 
						|
    const uint8_t *actionPos = (uint8_t*) actionEntry,
 | 
						|
                  *tempActionPos;
 | 
						|
    int64_t typeOffset = 0,
 | 
						|
            actionOffset;
 | 
						|
 | 
						|
    for (int i = 0; true; ++i) {
 | 
						|
        // Each emitted dwarf action corresponds to a 2 tuple of
 | 
						|
        // type info address offset, and action offset to the next
 | 
						|
        // emitted action.
 | 
						|
        typeOffset = readSLEB128(&actionPos);
 | 
						|
        tempActionPos = actionPos;
 | 
						|
        actionOffset = readSLEB128(&tempActionPos);
 | 
						|
 | 
						|
#ifdef DEBUG
 | 
						|
        fprintf(stderr,
 | 
						|
                "handleActionValue(...):typeOffset: <%lld>, "
 | 
						|
                    "actionOffset: <%lld>.\n",
 | 
						|
                typeOffset,
 | 
						|
                actionOffset);
 | 
						|
#endif
 | 
						|
        assert((typeOffset >= 0) && 
 | 
						|
               "handleActionValue(...):filters are not supported.");
 | 
						|
 | 
						|
        // Note: A typeOffset == 0 implies that a cleanup llvm.eh.selector
 | 
						|
        //       argument has been matched.
 | 
						|
        if ((typeOffset > 0) &&
 | 
						|
            (type == (classInfo[-typeOffset])->type)) {
 | 
						|
#ifdef DEBUG
 | 
						|
            fprintf(stderr,
 | 
						|
                    "handleActionValue(...):actionValue <%d> found.\n",
 | 
						|
                    i);
 | 
						|
#endif
 | 
						|
            *resultAction = i + 1;
 | 
						|
            ret = true;
 | 
						|
            break;
 | 
						|
        }
 | 
						|
 | 
						|
#ifdef DEBUG
 | 
						|
        fprintf(stderr,
 | 
						|
                "handleActionValue(...):actionValue not found.\n");
 | 
						|
#endif
 | 
						|
        if (!actionOffset)
 | 
						|
            break;
 | 
						|
 | 
						|
        actionPos += actionOffset;
 | 
						|
    }
 | 
						|
 | 
						|
    return(ret);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Deals with the Language specific data portion of the emitted dwarf code.
 | 
						|
/// See @link http://refspecs.freestandards.org/abi-eh-1.21.html @unlink
 | 
						|
/// @param version unsupported (ignored), unwind version
 | 
						|
/// @param lsda language specific data area
 | 
						|
/// @param _Unwind_Action actions minimally supported unwind stage 
 | 
						|
///        (forced specifically not supported)
 | 
						|
/// @param exceptionClass exception class (_Unwind_Exception::exception_class)
 | 
						|
///        of thrown exception.
 | 
						|
/// @param exceptionObject thrown _Unwind_Exception instance.
 | 
						|
/// @param context unwind system context
 | 
						|
/// @returns minimally supported unwinding control indicator 
 | 
						|
static _Unwind_Reason_Code handleLsda(int version, 
 | 
						|
                                  const uint8_t* lsda,
 | 
						|
                                  _Unwind_Action actions,
 | 
						|
                                  uint64_t exceptionClass, 
 | 
						|
                                  struct _Unwind_Exception* exceptionObject,
 | 
						|
                                  _Unwind_Context_t context) {
 | 
						|
    _Unwind_Reason_Code ret = _URC_CONTINUE_UNWIND;
 | 
						|
 | 
						|
    if (!lsda)
 | 
						|
        return(ret);
 | 
						|
 | 
						|
#ifdef DEBUG
 | 
						|
    fprintf(stderr, 
 | 
						|
            "handleLsda(...):lsda is non-zero.\n");
 | 
						|
#endif
 | 
						|
 | 
						|
    // Get the current instruction pointer and offset it before next
 | 
						|
    // instruction in the current frame which threw the exception.
 | 
						|
    uintptr_t pc = _Unwind_GetIP(context)-1;
 | 
						|
 | 
						|
    // Get beginning current frame's code (as defined by the 
 | 
						|
    // emitted dwarf code)
 | 
						|
    uintptr_t funcStart = _Unwind_GetRegionStart(context);
 | 
						|
    uintptr_t pcOffset = pc - funcStart;
 | 
						|
    struct OurExceptionType_t** classInfo = NULL;
 | 
						|
 | 
						|
    // Note: See JITDwarfEmitter::EmitExceptionTable(...) for corresponding
 | 
						|
    //       dwarf emission
 | 
						|
 | 
						|
    // Parse LSDA header.
 | 
						|
    uint8_t lpStartEncoding = *lsda++;
 | 
						|
 | 
						|
    if (lpStartEncoding != llvm::dwarf::DW_EH_PE_omit) {
 | 
						|
        readEncodedPointer(&lsda, lpStartEncoding); 
 | 
						|
    }
 | 
						|
 | 
						|
    uint8_t ttypeEncoding = *lsda++;
 | 
						|
    uintptr_t classInfoOffset;
 | 
						|
 | 
						|
    if (ttypeEncoding != llvm::dwarf::DW_EH_PE_omit) {
 | 
						|
        // Calculate type info locations in emitted dwarf code which
 | 
						|
        // were flagged by type info arguments to llvm.eh.selector
 | 
						|
        // intrinsic
 | 
						|
        classInfoOffset = readULEB128(&lsda);
 | 
						|
        classInfo = (struct OurExceptionType_t**) (lsda + classInfoOffset);
 | 
						|
    }
 | 
						|
 | 
						|
    // Walk call-site table looking for range that 
 | 
						|
    // includes current PC. 
 | 
						|
 | 
						|
    uint8_t         callSiteEncoding = *lsda++;
 | 
						|
    uint32_t        callSiteTableLength = readULEB128(&lsda);
 | 
						|
    const uint8_t*  callSiteTableStart = lsda;
 | 
						|
    const uint8_t*  callSiteTableEnd = callSiteTableStart + 
 | 
						|
                                                    callSiteTableLength;
 | 
						|
    const uint8_t*  actionTableStart = callSiteTableEnd;
 | 
						|
    const uint8_t*  callSitePtr = callSiteTableStart;
 | 
						|
 | 
						|
    bool foreignException = false;
 | 
						|
 | 
						|
    while (callSitePtr < callSiteTableEnd) {
 | 
						|
        uintptr_t start = readEncodedPointer(&callSitePtr, 
 | 
						|
                                             callSiteEncoding);
 | 
						|
        uintptr_t length = readEncodedPointer(&callSitePtr, 
 | 
						|
                                              callSiteEncoding);
 | 
						|
        uintptr_t landingPad = readEncodedPointer(&callSitePtr, 
 | 
						|
                                                  callSiteEncoding);
 | 
						|
 | 
						|
        // Note: Action value
 | 
						|
        uintptr_t actionEntry = readULEB128(&callSitePtr);
 | 
						|
 | 
						|
        if (exceptionClass != ourBaseExceptionClass) {
 | 
						|
            // We have been notified of a foreign exception being thrown,
 | 
						|
            // and we therefore need to execute cleanup landing pads
 | 
						|
            actionEntry = 0;
 | 
						|
            foreignException = true;
 | 
						|
        }
 | 
						|
 | 
						|
        if (landingPad == 0) {
 | 
						|
#ifdef DEBUG
 | 
						|
            fprintf(stderr,
 | 
						|
                    "handleLsda(...): No landing pad found.\n");
 | 
						|
#endif
 | 
						|
 | 
						|
            continue; // no landing pad for this entry
 | 
						|
        }
 | 
						|
 | 
						|
        if (actionEntry) {
 | 
						|
            actionEntry += ((uintptr_t) actionTableStart) - 1;
 | 
						|
        }
 | 
						|
        else {
 | 
						|
#ifdef DEBUG
 | 
						|
            fprintf(stderr,
 | 
						|
                    "handleLsda(...):No action table found.\n");
 | 
						|
#endif
 | 
						|
        }
 | 
						|
 | 
						|
        bool exceptionMatched = false;
 | 
						|
 | 
						|
        if ((start <= pcOffset) && (pcOffset < (start + length))) {
 | 
						|
#ifdef DEBUG
 | 
						|
            fprintf(stderr,
 | 
						|
                    "handleLsda(...): Landing pad found.\n");
 | 
						|
#endif
 | 
						|
            int64_t actionValue = 0;
 | 
						|
 | 
						|
            if (actionEntry) {
 | 
						|
                exceptionMatched = handleActionValue
 | 
						|
                                   (
 | 
						|
                                       &actionValue,
 | 
						|
                                       classInfo, 
 | 
						|
                                       actionEntry, 
 | 
						|
                                       exceptionClass, 
 | 
						|
                                       exceptionObject
 | 
						|
                                   );
 | 
						|
            }
 | 
						|
 | 
						|
            if (!(actions & _UA_SEARCH_PHASE)) {
 | 
						|
#ifdef DEBUG
 | 
						|
                fprintf(stderr,
 | 
						|
                        "handleLsda(...): installed landing pad "
 | 
						|
                            "context.\n");
 | 
						|
#endif
 | 
						|
 | 
						|
                // Found landing pad for the PC.
 | 
						|
                // Set Instruction Pointer to so we re-enter function 
 | 
						|
                // at landing pad. The landing pad is created by the 
 | 
						|
                // compiler to take two parameters in registers.
 | 
						|
                _Unwind_SetGR(context, 
 | 
						|
                              __builtin_eh_return_data_regno(0), 
 | 
						|
                              (uintptr_t)exceptionObject);
 | 
						|
 | 
						|
                // Note: this virtual register directly corresponds
 | 
						|
                //       to the return of the llvm.eh.selector intrinsic
 | 
						|
                if (!actionEntry || !exceptionMatched) {
 | 
						|
                    // We indicate cleanup only
 | 
						|
                    _Unwind_SetGR(context, 
 | 
						|
                                  __builtin_eh_return_data_regno(1), 
 | 
						|
                                  0);
 | 
						|
                }
 | 
						|
                else {
 | 
						|
                    // Matched type info index of llvm.eh.selector intrinsic
 | 
						|
                    // passed here.
 | 
						|
                    _Unwind_SetGR(context, 
 | 
						|
                                  __builtin_eh_return_data_regno(1), 
 | 
						|
                                  actionValue);
 | 
						|
                }
 | 
						|
 | 
						|
                // To execute landing pad set here
 | 
						|
                _Unwind_SetIP(context, funcStart + landingPad);
 | 
						|
                ret = _URC_INSTALL_CONTEXT;
 | 
						|
            }
 | 
						|
            else if (exceptionMatched) {
 | 
						|
#ifdef DEBUG
 | 
						|
                fprintf(stderr,
 | 
						|
                        "handleLsda(...): setting handler found.\n");
 | 
						|
#endif
 | 
						|
                ret = _URC_HANDLER_FOUND;
 | 
						|
            }
 | 
						|
            else {
 | 
						|
                // Note: Only non-clean up handlers are marked as
 | 
						|
                //       found. Otherwise the clean up handlers will be 
 | 
						|
                //       re-found and executed during the clean up 
 | 
						|
                //       phase.
 | 
						|
#ifdef DEBUG
 | 
						|
                fprintf(stderr,
 | 
						|
                        "handleLsda(...): cleanup handler found.\n");
 | 
						|
#endif
 | 
						|
            }
 | 
						|
 | 
						|
            break;
 | 
						|
        }
 | 
						|
    }
 | 
						|
 | 
						|
    return(ret);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// This is the personality function which is embedded (dwarf emitted), in the
 | 
						|
/// dwarf unwind info block. Again see: JITDwarfEmitter.cpp.
 | 
						|
/// See @link http://refspecs.freestandards.org/abi-eh-1.21.html @unlink
 | 
						|
/// @param version unsupported (ignored), unwind version
 | 
						|
/// @param _Unwind_Action actions minimally supported unwind stage 
 | 
						|
///        (forced specifically not supported)
 | 
						|
/// @param exceptionClass exception class (_Unwind_Exception::exception_class)
 | 
						|
///        of thrown exception.
 | 
						|
/// @param exceptionObject thrown _Unwind_Exception instance.
 | 
						|
/// @param context unwind system context
 | 
						|
/// @returns minimally supported unwinding control indicator 
 | 
						|
_Unwind_Reason_Code ourPersonality(int version, 
 | 
						|
                               _Unwind_Action actions,
 | 
						|
                               uint64_t exceptionClass, 
 | 
						|
                               struct _Unwind_Exception* exceptionObject,
 | 
						|
                               _Unwind_Context_t context) {
 | 
						|
#ifdef DEBUG
 | 
						|
    fprintf(stderr, 
 | 
						|
            "We are in ourPersonality(...):actions is <%d>.\n",
 | 
						|
            actions);
 | 
						|
 | 
						|
    if (actions & _UA_SEARCH_PHASE) {
 | 
						|
        fprintf(stderr, "ourPersonality(...):In search phase.\n");
 | 
						|
    }
 | 
						|
    else {
 | 
						|
        fprintf(stderr, "ourPersonality(...):In non-search phase.\n");
 | 
						|
    }
 | 
						|
#endif
 | 
						|
 | 
						|
    const uint8_t* lsda = _Unwind_GetLanguageSpecificData(context);
 | 
						|
 | 
						|
#ifdef DEBUG
 | 
						|
    fprintf(stderr, 
 | 
						|
            "ourPersonality(...):lsda = <%p>.\n",
 | 
						|
            lsda);
 | 
						|
#endif
 | 
						|
 | 
						|
    // The real work of the personality function is captured here
 | 
						|
    return(handleLsda(version,
 | 
						|
                      lsda,
 | 
						|
                      actions,
 | 
						|
                      exceptionClass,
 | 
						|
                      exceptionObject,
 | 
						|
                      context));
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Generates our _Unwind_Exception class from a given character array.
 | 
						|
/// thereby handling arbitrary lengths (not in standard), and handling
 | 
						|
/// embedded \0s.
 | 
						|
/// See @link http://refspecs.freestandards.org/abi-eh-1.21.html @unlink
 | 
						|
/// @param classChars char array to encode. NULL values not checkedf
 | 
						|
/// @param classCharsSize number of chars in classChars. Value is not checked.
 | 
						|
/// @returns class value
 | 
						|
uint64_t genClass(const unsigned char classChars[], size_t classCharsSize)
 | 
						|
{
 | 
						|
    uint64_t ret = classChars[0];
 | 
						|
 | 
						|
    for (unsigned i = 1; i < classCharsSize; ++i) {
 | 
						|
        ret <<= 8;
 | 
						|
        ret += classChars[i];
 | 
						|
    }
 | 
						|
 | 
						|
    return(ret);
 | 
						|
}
 | 
						|
 | 
						|
} // extern "C"
 | 
						|
 | 
						|
//
 | 
						|
// Runtime C Library functions End
 | 
						|
//
 | 
						|
 | 
						|
//
 | 
						|
// Code generation functions
 | 
						|
//
 | 
						|
 | 
						|
/// Generates code to print given constant string
 | 
						|
/// @param context llvm context
 | 
						|
/// @param module code for module instance
 | 
						|
/// @param builder builder instance
 | 
						|
/// @param toPrint string to print
 | 
						|
/// @param useGlobal A value of true (default) indicates a GlobalValue is 
 | 
						|
///        generated, and is used to hold the constant string. A value of 
 | 
						|
///        false indicates that the constant string will be stored on the 
 | 
						|
///        stack.
 | 
						|
void generateStringPrint(llvm::LLVMContext& context, 
 | 
						|
                         llvm::Module& module,
 | 
						|
                         llvm::IRBuilder<>& builder, 
 | 
						|
                         std::string toPrint,
 | 
						|
                         bool useGlobal = true) {
 | 
						|
    llvm::Function *printFunct = module.getFunction("printStr");
 | 
						|
 | 
						|
    llvm::Value *stringVar;
 | 
						|
    llvm::Constant* stringConstant = 
 | 
						|
        llvm::ConstantArray::get(context, toPrint);
 | 
						|
 | 
						|
    if (useGlobal) {
 | 
						|
        // Note: Does not work without allocation
 | 
						|
        stringVar = 
 | 
						|
            new llvm::GlobalVariable(module, 
 | 
						|
                                     stringConstant->getType(),
 | 
						|
                                     true, 
 | 
						|
                                     llvm::GlobalValue::LinkerPrivateLinkage, 
 | 
						|
                                     stringConstant, 
 | 
						|
                                     "");
 | 
						|
    }
 | 
						|
    else {
 | 
						|
        stringVar = builder.CreateAlloca(stringConstant->getType());
 | 
						|
        builder.CreateStore(stringConstant, stringVar);
 | 
						|
    }
 | 
						|
 | 
						|
    llvm::Value* cast = 
 | 
						|
        builder.CreatePointerCast(stringVar, 
 | 
						|
                                  builder.getInt8Ty()->getPointerTo());
 | 
						|
    builder.CreateCall(printFunct, cast);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Generates code to print given runtime integer according to constant
 | 
						|
/// string format, and a given print function.
 | 
						|
/// @param context llvm context
 | 
						|
/// @param module code for module instance
 | 
						|
/// @param builder builder instance
 | 
						|
/// @param printFunct function used to "print" integer
 | 
						|
/// @param toPrint string to print
 | 
						|
/// @param format printf like formating string for print
 | 
						|
/// @param useGlobal A value of true (default) indicates a GlobalValue is 
 | 
						|
///        generated, and is used to hold the constant string. A value of 
 | 
						|
///        false indicates that the constant string will be stored on the 
 | 
						|
///        stack.
 | 
						|
void generateIntegerPrint(llvm::LLVMContext& context, 
 | 
						|
                          llvm::Module& module,
 | 
						|
                          llvm::IRBuilder<>& builder, 
 | 
						|
                          llvm::Function& printFunct,
 | 
						|
                          llvm::Value& toPrint,
 | 
						|
                          std::string format, 
 | 
						|
                          bool useGlobal = true) {
 | 
						|
    llvm::Constant *stringConstant = llvm::ConstantArray::get(context, format);
 | 
						|
    llvm::Value *stringVar;
 | 
						|
 | 
						|
    if (useGlobal) {
 | 
						|
        // Note: Does not seem to work without allocation
 | 
						|
        stringVar = 
 | 
						|
            new llvm::GlobalVariable(module, 
 | 
						|
                                     stringConstant->getType(),
 | 
						|
                                    true, 
 | 
						|
                                     llvm::GlobalValue::LinkerPrivateLinkage, 
 | 
						|
                                     stringConstant, 
 | 
						|
                                     "");
 | 
						|
    }
 | 
						|
    else {
 | 
						|
        stringVar = builder.CreateAlloca(stringConstant->getType());
 | 
						|
        builder.CreateStore(stringConstant, stringVar);
 | 
						|
    }
 | 
						|
 | 
						|
    llvm::Value* cast = 
 | 
						|
        builder.CreateBitCast(stringVar, 
 | 
						|
                              builder.getInt8Ty()->getPointerTo());
 | 
						|
    builder.CreateCall2(&printFunct, &toPrint, cast);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Generates code to handle finally block type semantics: always runs 
 | 
						|
/// regardless of whether a thrown exception is passing through or the 
 | 
						|
/// parent function is simply exiting. In addition to printing some state 
 | 
						|
/// to stderr, this code will resume the exception handling--runs the 
 | 
						|
/// unwind resume block, if the exception has not been previously caught 
 | 
						|
/// by a catch clause, and will otherwise execute the end block (terminator 
 | 
						|
/// block). In addition this function creates the corresponding function's 
 | 
						|
/// stack storage for the exception pointer and catch flag status.
 | 
						|
/// @param context llvm context
 | 
						|
/// @param module code for module instance
 | 
						|
/// @param builder builder instance
 | 
						|
/// @param toAddTo parent function to add block to
 | 
						|
/// @param blockName block name of new "finally" block.
 | 
						|
/// @param functionId output id used for printing
 | 
						|
/// @param terminatorBlock terminator "end" block
 | 
						|
/// @param unwindResumeBlock unwind resume block
 | 
						|
/// @param exceptionCaughtFlag reference exception caught/thrown status storage
 | 
						|
/// @param exceptionStorage reference to exception pointer storage
 | 
						|
/// @returns newly created block
 | 
						|
static llvm::BasicBlock* createFinallyBlock(llvm::LLVMContext& context, 
 | 
						|
                             llvm::Module& module, 
 | 
						|
                             llvm::IRBuilder<>& builder, 
 | 
						|
                             llvm::Function& toAddTo,
 | 
						|
                             std::string& blockName,
 | 
						|
                             std::string& functionId,
 | 
						|
                             llvm::BasicBlock& terminatorBlock,
 | 
						|
                             llvm::BasicBlock& unwindResumeBlock,
 | 
						|
                             llvm::Value** exceptionCaughtFlag,
 | 
						|
                             llvm::Value** exceptionStorage) {
 | 
						|
    assert(exceptionCaughtFlag && 
 | 
						|
           "ExceptionDemo::createFinallyBlock(...):exceptionCaughtFlag "
 | 
						|
               "is NULL");
 | 
						|
    assert(exceptionStorage && 
 | 
						|
           "ExceptionDemo::createFinallyBlock(...):exceptionStorage "
 | 
						|
               "is NULL");
 | 
						|
 | 
						|
    *exceptionCaughtFlag = 
 | 
						|
        createEntryBlockAlloca(toAddTo,
 | 
						|
                               "exceptionCaught",
 | 
						|
                               ourExceptionNotThrownState->getType(),
 | 
						|
                               ourExceptionNotThrownState);
 | 
						|
 | 
						|
    const llvm::PointerType* exceptionStorageType = 
 | 
						|
                                builder.getInt8Ty()->getPointerTo();
 | 
						|
    *exceptionStorage = 
 | 
						|
        createEntryBlockAlloca(toAddTo,
 | 
						|
                               "exceptionStorage",
 | 
						|
                               exceptionStorageType,
 | 
						|
                               llvm::ConstantPointerNull::get(
 | 
						|
                                   exceptionStorageType));
 | 
						|
 | 
						|
    llvm::BasicBlock *ret = llvm::BasicBlock::Create(context,
 | 
						|
                                                     blockName,
 | 
						|
                                                     &toAddTo);
 | 
						|
 | 
						|
    builder.SetInsertPoint(ret);
 | 
						|
   
 | 
						|
    std::ostringstream bufferToPrint;
 | 
						|
    bufferToPrint << "Gen: Executing finally block "
 | 
						|
                  << blockName
 | 
						|
                  << " in "
 | 
						|
                  << functionId
 | 
						|
                  << std::endl;
 | 
						|
    generateStringPrint(context, 
 | 
						|
                        module, 
 | 
						|
                        builder, 
 | 
						|
                        bufferToPrint.str(),
 | 
						|
                        USE_GLOBAL_STR_CONSTS);
 | 
						|
 | 
						|
    llvm::SwitchInst* theSwitch = 
 | 
						|
        builder.CreateSwitch(builder.CreateLoad(*exceptionCaughtFlag), 
 | 
						|
                             &terminatorBlock,
 | 
						|
                             2);
 | 
						|
    theSwitch->addCase(ourExceptionCaughtState, &terminatorBlock);
 | 
						|
    theSwitch->addCase(ourExceptionThrownState, &unwindResumeBlock);
 | 
						|
 | 
						|
    return(ret);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Generates catch block semantics which print a string to indicate type of
 | 
						|
/// catch executed, sets an exception caught flag, and executes passed in 
 | 
						|
/// end block (terminator block).
 | 
						|
/// @param context llvm context
 | 
						|
/// @param module code for module instance
 | 
						|
/// @param builder builder instance
 | 
						|
/// @param toAddTo parent function to add block to
 | 
						|
/// @param blockName block name of new "catch" block.
 | 
						|
/// @param functionId output id used for printing
 | 
						|
/// @param terminatorBlock terminator "end" block
 | 
						|
/// @param exceptionCaughtFlag exception caught/thrown status
 | 
						|
/// @returns newly created block
 | 
						|
static llvm::BasicBlock* createCatchBlock(llvm::LLVMContext& context, 
 | 
						|
                                          llvm::Module& module, 
 | 
						|
                                          llvm::IRBuilder<>& builder, 
 | 
						|
                                          llvm::Function& toAddTo,
 | 
						|
                                          std::string& blockName,
 | 
						|
                                          std::string& functionId,
 | 
						|
                                          llvm::BasicBlock& terminatorBlock,
 | 
						|
                                          llvm::Value& exceptionCaughtFlag) {
 | 
						|
 | 
						|
    llvm::BasicBlock *ret = llvm::BasicBlock::Create(context,
 | 
						|
                                                     blockName,
 | 
						|
                                                     &toAddTo);
 | 
						|
 | 
						|
    builder.SetInsertPoint(ret);
 | 
						|
 | 
						|
    std::ostringstream bufferToPrint;
 | 
						|
    bufferToPrint << "Gen: Executing catch block "
 | 
						|
                  << blockName
 | 
						|
                  << " in "
 | 
						|
                  << functionId
 | 
						|
                  << std::endl;
 | 
						|
    generateStringPrint(context, 
 | 
						|
                        module, 
 | 
						|
                        builder, 
 | 
						|
                        bufferToPrint.str(),
 | 
						|
                        USE_GLOBAL_STR_CONSTS);
 | 
						|
    builder.CreateStore(ourExceptionCaughtState, &exceptionCaughtFlag);
 | 
						|
    builder.CreateBr(&terminatorBlock);
 | 
						|
 | 
						|
    return(ret);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Generates a function which invokes a function (toInvoke) and, whose 
 | 
						|
/// unwind block will "catch" the type info types correspondingly held in the 
 | 
						|
/// exceptionTypesToCatch argument. If the toInvoke function throws an 
 | 
						|
/// exception which does not match any type info types contained in 
 | 
						|
/// exceptionTypesToCatch, the generated code will call _Unwind_Resume 
 | 
						|
/// with the raised exception. On the other hand the generated code will 
 | 
						|
/// normally exit if the toInvoke function does not throw an exception.
 | 
						|
/// The generated "finally" block is always run regardless of the cause of 
 | 
						|
/// the generated function exit.
 | 
						|
/// The generated function is returned after being verified.
 | 
						|
/// @param module code for module instance
 | 
						|
/// @param builder builder instance
 | 
						|
/// @param fpm a function pass manager holding optional IR to IR 
 | 
						|
///        transformations
 | 
						|
/// @param toInvoke inner function to invoke
 | 
						|
/// @param ourId id used to printing purposes
 | 
						|
/// @param numExceptionsToCatch length of exceptionTypesToCatch array
 | 
						|
/// @param exceptionTypesToCatch array of type info types to "catch"
 | 
						|
/// @returns generated function
 | 
						|
static
 | 
						|
llvm::Function* createCatchWrappedInvokeFunction(llvm::Module& module, 
 | 
						|
                    llvm::IRBuilder<>& builder, 
 | 
						|
                    llvm::FunctionPassManager& fpm,
 | 
						|
                    llvm::Function& toInvoke,
 | 
						|
                    std::string ourId,
 | 
						|
                    unsigned numExceptionsToCatch,
 | 
						|
                    unsigned exceptionTypesToCatch[]) {
 | 
						|
 | 
						|
    llvm::LLVMContext& context = module.getContext();
 | 
						|
    llvm::Function *toPrint32Int = module.getFunction("print32Int");
 | 
						|
 | 
						|
    ArgTypes argTypes;
 | 
						|
    argTypes.push_back(builder.getInt32Ty());
 | 
						|
 | 
						|
    ArgNames argNames;
 | 
						|
    argNames.push_back("exceptTypeToThrow");
 | 
						|
 | 
						|
    llvm::Function* ret = createFunction(module, 
 | 
						|
                                         builder.getVoidTy(),
 | 
						|
                                         argTypes, 
 | 
						|
                                         argNames, 
 | 
						|
                                         ourId,
 | 
						|
                                         llvm::Function::ExternalLinkage, 
 | 
						|
                                         false, 
 | 
						|
                                         false);
 | 
						|
 | 
						|
    // Block which calls invoke
 | 
						|
    llvm::BasicBlock *entryBlock = llvm::BasicBlock::Create(context,
 | 
						|
                                                            "entry", 
 | 
						|
                                                            ret);
 | 
						|
    // Normal block for invoke
 | 
						|
    llvm::BasicBlock *normalBlock = llvm::BasicBlock::Create(context, 
 | 
						|
                                                             "normal", 
 | 
						|
                                                             ret);
 | 
						|
    // Unwind block for invoke
 | 
						|
    llvm::BasicBlock *exceptionBlock = 
 | 
						|
        llvm::BasicBlock::Create(context, "exception", ret);
 | 
						|
 | 
						|
    // Block which routes exception to correct catch handler block
 | 
						|
    llvm::BasicBlock *exceptionRouteBlock = 
 | 
						|
        llvm::BasicBlock::Create(context, "exceptionRoute", ret);
 | 
						|
 | 
						|
    // Foreign exception handler
 | 
						|
    llvm::BasicBlock *externalExceptionBlock = 
 | 
						|
        llvm::BasicBlock::Create(context, "externalException", ret);
 | 
						|
 | 
						|
    // Block which calls _Unwind_Resume
 | 
						|
    llvm::BasicBlock *unwindResumeBlock = 
 | 
						|
        llvm::BasicBlock::Create(context, "unwindResume", ret);
 | 
						|
 | 
						|
    // Clean up block which delete exception if needed
 | 
						|
    llvm::BasicBlock *endBlock = 
 | 
						|
        llvm::BasicBlock::Create(context, "end", ret);
 | 
						|
 | 
						|
    std::string nextName;
 | 
						|
    std::vector<llvm::BasicBlock*> catchBlocks(numExceptionsToCatch);
 | 
						|
    llvm::Value* exceptionCaughtFlag = NULL;
 | 
						|
    llvm::Value* exceptionStorage = NULL;
 | 
						|
 | 
						|
    // Finally block which will branch to unwindResumeBlock if 
 | 
						|
    // exception is not caught. Initializes/allocates stack locations.
 | 
						|
    llvm::BasicBlock* finallyBlock = createFinallyBlock(context, 
 | 
						|
                                                        module, 
 | 
						|
                                                        builder, 
 | 
						|
                                                        *ret, 
 | 
						|
                                                        nextName = "finally", 
 | 
						|
                                                        ourId,
 | 
						|
                                                        *endBlock,
 | 
						|
                                                        *unwindResumeBlock,
 | 
						|
                                                        &exceptionCaughtFlag,
 | 
						|
                                                        &exceptionStorage);
 | 
						|
 | 
						|
    for (unsigned i = 0; i < numExceptionsToCatch; ++i) {
 | 
						|
        nextName = ourTypeInfoNames[exceptionTypesToCatch[i]];
 | 
						|
 | 
						|
        // One catch block per type info to be caught
 | 
						|
        catchBlocks[i] = createCatchBlock(context, 
 | 
						|
                                          module, 
 | 
						|
                                          builder, 
 | 
						|
                                          *ret,
 | 
						|
                                          nextName, 
 | 
						|
                                          ourId,
 | 
						|
                                          *finallyBlock,
 | 
						|
                                          *exceptionCaughtFlag);
 | 
						|
    }
 | 
						|
 | 
						|
    // Entry Block
 | 
						|
 | 
						|
    builder.SetInsertPoint(entryBlock);
 | 
						|
 | 
						|
    std::vector<llvm::Value*> args;
 | 
						|
    args.push_back(namedValues["exceptTypeToThrow"]);
 | 
						|
    builder.CreateInvoke(&toInvoke, 
 | 
						|
                         normalBlock, 
 | 
						|
                         exceptionBlock, 
 | 
						|
                         args.begin(), 
 | 
						|
                         args.end());
 | 
						|
 | 
						|
    // End Block
 | 
						|
 | 
						|
    builder.SetInsertPoint(endBlock);
 | 
						|
 | 
						|
    generateStringPrint(context, 
 | 
						|
                        module,
 | 
						|
                        builder, 
 | 
						|
                        "Gen: In end block: exiting in " + ourId + ".\n",
 | 
						|
                        USE_GLOBAL_STR_CONSTS);
 | 
						|
    llvm::Function *deleteOurException = 
 | 
						|
                                    module.getFunction("deleteOurException");
 | 
						|
 | 
						|
    // Note: function handles NULL exceptions
 | 
						|
    builder.CreateCall(deleteOurException, 
 | 
						|
                       builder.CreateLoad(exceptionStorage));
 | 
						|
    builder.CreateRetVoid();
 | 
						|
 | 
						|
    // Normal Block
 | 
						|
 | 
						|
    builder.SetInsertPoint(normalBlock);
 | 
						|
 | 
						|
    generateStringPrint(context, 
 | 
						|
                        module,
 | 
						|
                        builder, 
 | 
						|
                        "Gen: No exception in " + ourId + "!\n",
 | 
						|
                        USE_GLOBAL_STR_CONSTS);
 | 
						|
 | 
						|
    // Finally block is always called
 | 
						|
    builder.CreateBr(finallyBlock);
 | 
						|
 | 
						|
    // Unwind Resume Block
 | 
						|
 | 
						|
    builder.SetInsertPoint(unwindResumeBlock);
 | 
						|
 | 
						|
    llvm::Function *resumeOurException = 
 | 
						|
                module.getFunction("_Unwind_Resume");
 | 
						|
    builder.CreateCall(resumeOurException, 
 | 
						|
                       builder.CreateLoad(exceptionStorage));
 | 
						|
    builder.CreateUnreachable();
 | 
						|
 | 
						|
    // Exception Block
 | 
						|
 | 
						|
    builder.SetInsertPoint(exceptionBlock);
 | 
						|
 | 
						|
    llvm::Function *ehException = module.getFunction("llvm.eh.exception");
 | 
						|
 | 
						|
    // Retrieve thrown exception
 | 
						|
    llvm::Value* unwindException = builder.CreateCall(ehException);
 | 
						|
 | 
						|
    // Store exception and flag
 | 
						|
    builder.CreateStore(unwindException, exceptionStorage);
 | 
						|
    builder.CreateStore(ourExceptionThrownState, exceptionCaughtFlag);
 | 
						|
    llvm::Function *personality = module.getFunction("ourPersonality");
 | 
						|
    llvm::Value* functPtr = 
 | 
						|
        builder.CreatePointerCast(personality, 
 | 
						|
                              builder.getInt8Ty()->getPointerTo());
 | 
						|
 | 
						|
    args.clear();
 | 
						|
    args.push_back(unwindException);
 | 
						|
    args.push_back(functPtr);
 | 
						|
 | 
						|
    // Note: Skipping index 0
 | 
						|
    for (unsigned i = 0; i < numExceptionsToCatch; ++i) {
 | 
						|
        // Set up type infos to be caught
 | 
						|
        args.push_back(
 | 
						|
            module.getGlobalVariable(
 | 
						|
                ourTypeInfoNames[exceptionTypesToCatch[i]]));
 | 
						|
    }
 | 
						|
 | 
						|
    args.push_back(llvm::ConstantInt::get(builder.getInt32Ty(), 0));
 | 
						|
 | 
						|
    llvm::Function *ehSelector = module.getFunction("llvm.eh.selector");
 | 
						|
 | 
						|
    // Set up this exeption block as the landing pad which will handle
 | 
						|
    // given type infos. See case Intrinsic::eh_selector in 
 | 
						|
    // SelectionDAGBuilder::visitIntrinsicCall(...) and AddCatchInfo(...)
 | 
						|
    // implemented in FunctionLoweringInfo.cpp to see how the implementation
 | 
						|
    // handles this call. This landing pad (this exception block), will be 
 | 
						|
    // called either because it nees to cleanup (call finally) or a type 
 | 
						|
    // info was found which matched the thrown exception.
 | 
						|
    llvm::Value* retTypeInfoIndex = builder.CreateCall(ehSelector, 
 | 
						|
                                                       args.begin(), 
 | 
						|
                                                       args.end());
 | 
						|
 | 
						|
    // Retrieve exception_class member from thrown exception 
 | 
						|
    // (_Unwind_Exception instance). This member tells us whether or not
 | 
						|
    // the exception is foreign.
 | 
						|
    llvm::Value* unwindExceptionClass = 
 | 
						|
        builder.CreateLoad(
 | 
						|
            builder.CreateStructGEP(
 | 
						|
                builder.CreatePointerCast(
 | 
						|
                    unwindException, 
 | 
						|
                    ourUnwindExceptionType->getPointerTo()), 
 | 
						|
                0));
 | 
						|
 | 
						|
    // Branch to the externalExceptionBlock if the exception is foreign or
 | 
						|
    // to a catch router if not. Either way the finally block will be run.
 | 
						|
    builder.CreateCondBr(
 | 
						|
        builder.CreateICmpEQ(unwindExceptionClass,
 | 
						|
                             llvm::ConstantInt::get(builder.getInt64Ty(), 
 | 
						|
                                                    ourBaseExceptionClass)),
 | 
						|
        exceptionRouteBlock,
 | 
						|
        externalExceptionBlock);
 | 
						|
 | 
						|
    // External Exception Block
 | 
						|
 | 
						|
    builder.SetInsertPoint(externalExceptionBlock);
 | 
						|
 | 
						|
    generateStringPrint(context, 
 | 
						|
                        module,
 | 
						|
                        builder, 
 | 
						|
                        "Gen: Foreign exception received.\n",
 | 
						|
                        USE_GLOBAL_STR_CONSTS);
 | 
						|
 | 
						|
    // Branch to the finally block
 | 
						|
    builder.CreateBr(finallyBlock);
 | 
						|
 | 
						|
    // Exception Route Block
 | 
						|
 | 
						|
    builder.SetInsertPoint(exceptionRouteBlock);
 | 
						|
 | 
						|
    // Casts exception pointer (_Unwind_Exception instance) to parent 
 | 
						|
    // (OurException instance).
 | 
						|
    //
 | 
						|
    // Note: ourBaseFromUnwindOffset is usually negative
 | 
						|
    llvm::Value* typeInfoThrown = 
 | 
						|
        builder.CreatePointerCast(
 | 
						|
            builder.CreateConstGEP1_64(unwindException,
 | 
						|
                                       ourBaseFromUnwindOffset),
 | 
						|
            ourExceptionType->getPointerTo());
 | 
						|
 | 
						|
    // Retrieve thrown exception type info type
 | 
						|
    //
 | 
						|
    // Note: Index is not relative to pointer but instead to structure
 | 
						|
    //       unlike a true getelementptr (GEP) instruction
 | 
						|
    typeInfoThrown = builder.CreateStructGEP(typeInfoThrown, 0);
 | 
						|
 | 
						|
    llvm::Value* typeInfoThrownType = 
 | 
						|
                     builder.CreateStructGEP(typeInfoThrown, 0);
 | 
						|
 | 
						|
    generateIntegerPrint(context, 
 | 
						|
                         module,
 | 
						|
                         builder, 
 | 
						|
                         *toPrint32Int, 
 | 
						|
                         *(builder.CreateLoad(typeInfoThrownType)),
 | 
						|
                         "Gen: Exception type <%d> received (stack unwound) " 
 | 
						|
                                 " in " + 
 | 
						|
                             ourId + 
 | 
						|
                             ".\n",
 | 
						|
                         USE_GLOBAL_STR_CONSTS);
 | 
						|
 | 
						|
    // Route to matched type info catch block or run cleanup finally block
 | 
						|
    llvm::SwitchInst* switchToCatchBlock = 
 | 
						|
        builder.CreateSwitch(retTypeInfoIndex, 
 | 
						|
                             finallyBlock, 
 | 
						|
                             numExceptionsToCatch);
 | 
						|
 | 
						|
    unsigned nextTypeToCatch;
 | 
						|
 | 
						|
    for (unsigned i = 1; i <= numExceptionsToCatch; ++i) {
 | 
						|
        nextTypeToCatch = i - 1;
 | 
						|
        switchToCatchBlock->addCase(llvm::ConstantInt::get(
 | 
						|
                                        llvm::Type::getInt32Ty(context), 
 | 
						|
                                        i),
 | 
						|
                                    catchBlocks[nextTypeToCatch]);
 | 
						|
    }
 | 
						|
 | 
						|
    llvm::verifyFunction(*ret);
 | 
						|
    fpm.run(*ret);
 | 
						|
 | 
						|
    return(ret);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Generates function which throws either an exception matched to a runtime
 | 
						|
/// determined type info type (argument to generated function), or if this 
 | 
						|
/// runtime value matches nativeThrowType, throws a foreign exception by 
 | 
						|
/// calling nativeThrowFunct.
 | 
						|
/// @param module code for module instance
 | 
						|
/// @param builder builder instance
 | 
						|
/// @param fpm a function pass manager holding optional IR to IR 
 | 
						|
///        transformations
 | 
						|
/// @param ourId id used to printing purposes
 | 
						|
/// @param nativeThrowType a runtime argument of this value results in
 | 
						|
///        nativeThrowFunct being called to generate/throw exception.
 | 
						|
/// @param nativeThrowFunct function which will throw a foreign exception
 | 
						|
///        if the above nativeThrowType matches generated function's arg.
 | 
						|
/// @returns generated function
 | 
						|
static
 | 
						|
llvm::Function* createThrowExceptionFunction(llvm::Module& module, 
 | 
						|
                                         llvm::IRBuilder<>& builder, 
 | 
						|
                                         llvm::FunctionPassManager& fpm,
 | 
						|
                                         std::string ourId,
 | 
						|
                                         int32_t nativeThrowType,
 | 
						|
                                         llvm::Function& nativeThrowFunct) {
 | 
						|
    llvm::LLVMContext& context = module.getContext();
 | 
						|
    namedValues.clear();
 | 
						|
    ArgTypes unwindArgTypes;
 | 
						|
    unwindArgTypes.push_back(builder.getInt32Ty());
 | 
						|
    ArgNames unwindArgNames;
 | 
						|
    unwindArgNames.push_back("exceptTypeToThrow");
 | 
						|
 | 
						|
    llvm::Function *ret = createFunction(module,
 | 
						|
                                         builder.getVoidTy(),
 | 
						|
                                         unwindArgTypes,
 | 
						|
                                         unwindArgNames,
 | 
						|
                                         ourId,
 | 
						|
                                         llvm::Function::ExternalLinkage,
 | 
						|
                                         false,
 | 
						|
                                         false);
 | 
						|
 | 
						|
    // Throws either one of our exception or a native C++ exception depending
 | 
						|
    // on a runtime argument value containing a type info type.
 | 
						|
    llvm::BasicBlock *entryBlock = llvm::BasicBlock::Create(context,
 | 
						|
                                                            "entry", 
 | 
						|
                                                            ret);
 | 
						|
    // Throws a foreign exception
 | 
						|
    llvm::BasicBlock *nativeThrowBlock = 
 | 
						|
                                llvm::BasicBlock::Create(context,
 | 
						|
                                                         "nativeThrow", 
 | 
						|
                                                         ret);
 | 
						|
    // Throws one of our Exceptions
 | 
						|
    llvm::BasicBlock *generatedThrowBlock = 
 | 
						|
                                llvm::BasicBlock::Create(context,
 | 
						|
                                                         "generatedThrow", 
 | 
						|
                                                         ret);
 | 
						|
    // Retrieved runtime type info type to throw
 | 
						|
    llvm::Value* exceptionType = namedValues["exceptTypeToThrow"];
 | 
						|
 | 
						|
    // nativeThrowBlock block
 | 
						|
 | 
						|
    builder.SetInsertPoint(nativeThrowBlock);
 | 
						|
 | 
						|
    // Throws foreign exception
 | 
						|
    builder.CreateCall(&nativeThrowFunct, exceptionType);
 | 
						|
    builder.CreateUnreachable();
 | 
						|
 | 
						|
    // entry block
 | 
						|
 | 
						|
    builder.SetInsertPoint(entryBlock);
 | 
						|
 | 
						|
    llvm::Function *toPrint32Int = module.getFunction("print32Int");
 | 
						|
    generateIntegerPrint(context, 
 | 
						|
                         module,
 | 
						|
                         builder, 
 | 
						|
                         *toPrint32Int, 
 | 
						|
                         *exceptionType, 
 | 
						|
                         "\nGen: About to throw exception type <%d> in " + 
 | 
						|
                             ourId + 
 | 
						|
                             ".\n",
 | 
						|
                         USE_GLOBAL_STR_CONSTS);
 | 
						|
 | 
						|
    // Switches on runtime type info type value to determine whether or not
 | 
						|
    // a foreign exception is thrown. Defaults to throwing one of our 
 | 
						|
    // generated exceptions.
 | 
						|
    llvm::SwitchInst* theSwitch = builder.CreateSwitch(exceptionType,
 | 
						|
                                                       generatedThrowBlock,
 | 
						|
                                                       1);
 | 
						|
 | 
						|
    theSwitch->addCase(llvm::ConstantInt::get(llvm::Type::getInt32Ty(context), 
 | 
						|
                                              nativeThrowType),
 | 
						|
                       nativeThrowBlock);
 | 
						|
 | 
						|
    // generatedThrow block
 | 
						|
 | 
						|
    builder.SetInsertPoint(generatedThrowBlock);
 | 
						|
 | 
						|
    llvm::Function *createOurException = 
 | 
						|
                module.getFunction("createOurException");
 | 
						|
    llvm::Function *raiseOurException = 
 | 
						|
                module.getFunction("_Unwind_RaiseException");
 | 
						|
 | 
						|
    // Creates exception to throw with runtime type info type.
 | 
						|
    llvm::Value* exception = 
 | 
						|
        builder.CreateCall(createOurException, 
 | 
						|
                           namedValues["exceptTypeToThrow"]);
 | 
						|
 | 
						|
    // Throw generated Exception
 | 
						|
    builder.CreateCall(raiseOurException, exception);
 | 
						|
    builder.CreateUnreachable();
 | 
						|
 | 
						|
    llvm::verifyFunction(*ret);
 | 
						|
    fpm.run(*ret);
 | 
						|
 | 
						|
    return(ret);
 | 
						|
}
 | 
						|
 | 
						|
static void createStandardUtilityFunctions(unsigned numTypeInfos,
 | 
						|
                                           llvm::Module& module, 
 | 
						|
                                           llvm::IRBuilder<>& builder);
 | 
						|
 | 
						|
/// Creates test code by generating and organizing these functions into the 
 | 
						|
/// test case. The test case consists of an outer function setup to invoke
 | 
						|
/// an inner function within an environment having multiple catch and single 
 | 
						|
/// finally blocks. This inner function is also setup to invoke a throw
 | 
						|
/// function within an evironment similar in nature to the outer function's 
 | 
						|
/// catch and finally blocks. Each of these two functions catch mutually
 | 
						|
/// exclusive subsets (even or odd) of the type info types configured
 | 
						|
/// for this this. All generated functions have a runtime argument which
 | 
						|
/// holds a type info type to throw that each function takes and passes it
 | 
						|
/// to the inner one if such a inner function exists. This type info type is
 | 
						|
/// looked at by the generated throw function to see whether or not it should
 | 
						|
/// throw a generated exception with the same type info type, or instead call
 | 
						|
/// a supplied a function which in turn will throw a foreign exception.
 | 
						|
/// @param module code for module instance
 | 
						|
/// @param builder builder instance
 | 
						|
/// @param fpm a function pass manager holding optional IR to IR 
 | 
						|
///        transformations
 | 
						|
/// @param nativeThrowFunctName name of external function which will throw
 | 
						|
///        a foreign exception
 | 
						|
/// @returns outermost generated test function.
 | 
						|
llvm::Function* createUnwindExceptionTest(llvm::Module& module, 
 | 
						|
                                          llvm::IRBuilder<>& builder, 
 | 
						|
                                          llvm::FunctionPassManager& fpm,
 | 
						|
                                          std::string nativeThrowFunctName) {
 | 
						|
    // Number of type infos to generate
 | 
						|
    unsigned numTypeInfos = 6;
 | 
						|
 | 
						|
    // Initialze intrisics and external functions to use along with exception
 | 
						|
    // and type info globals.
 | 
						|
    createStandardUtilityFunctions(numTypeInfos,
 | 
						|
                                   module,
 | 
						|
                                   builder);
 | 
						|
    llvm::Function *nativeThrowFunct = 
 | 
						|
        module.getFunction(nativeThrowFunctName);
 | 
						|
 | 
						|
    // Create exception throw function using the value ~0 to cause 
 | 
						|
    // foreign exceptions to be thrown.
 | 
						|
    llvm::Function* throwFunct = 
 | 
						|
                            createThrowExceptionFunction(module,
 | 
						|
                                                         builder,
 | 
						|
                                                         fpm,
 | 
						|
                                                         "throwFunct",
 | 
						|
                                                         ~0,
 | 
						|
                                                         *nativeThrowFunct);
 | 
						|
    // Inner function will catch even type infos
 | 
						|
    unsigned innerExceptionTypesToCatch[] = {6, 2, 4};
 | 
						|
    size_t numExceptionTypesToCatch = sizeof(innerExceptionTypesToCatch) / 
 | 
						|
                                          sizeof(unsigned);
 | 
						|
 | 
						|
    // Generate inner function.
 | 
						|
    llvm::Function* innerCatchFunct = 
 | 
						|
        createCatchWrappedInvokeFunction(module,
 | 
						|
                                         builder,
 | 
						|
                                         fpm,
 | 
						|
                                         *throwFunct,
 | 
						|
                                         "innerCatchFunct",
 | 
						|
                                         numExceptionTypesToCatch,
 | 
						|
                                         innerExceptionTypesToCatch);
 | 
						|
 | 
						|
    // Outer function will catch odd type infos
 | 
						|
    unsigned outerExceptionTypesToCatch[] = {3, 1, 5};
 | 
						|
    numExceptionTypesToCatch = sizeof(outerExceptionTypesToCatch) / 
 | 
						|
                                   sizeof(unsigned);
 | 
						|
 | 
						|
    // Generate outer function
 | 
						|
    llvm::Function* outerCatchFunct = 
 | 
						|
        createCatchWrappedInvokeFunction(module,
 | 
						|
                                         builder,
 | 
						|
                                         fpm,
 | 
						|
                                         *innerCatchFunct,
 | 
						|
                                         "outerCatchFunct",
 | 
						|
                                         numExceptionTypesToCatch,
 | 
						|
                                         outerExceptionTypesToCatch);
 | 
						|
 | 
						|
    // Return outer function to run
 | 
						|
    return(outerCatchFunct);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Represents our foreign exceptions
 | 
						|
class OurCppRunException : public std::runtime_error {
 | 
						|
public:
 | 
						|
    OurCppRunException(const std::string reason) :
 | 
						|
        std::runtime_error(reason) {}
 | 
						|
 | 
						|
    OurCppRunException (const OurCppRunException& toCopy) :
 | 
						|
        std::runtime_error(toCopy) {}
 | 
						|
 | 
						|
    OurCppRunException& operator = (const OurCppRunException& toCopy) {
 | 
						|
        return(reinterpret_cast<OurCppRunException&>(
 | 
						|
                   std::runtime_error::operator = (toCopy)
 | 
						|
               ));
 | 
						|
    }
 | 
						|
 | 
						|
    ~OurCppRunException (void) throw () {}
 | 
						|
};
 | 
						|
 | 
						|
 | 
						|
/// Throws foreign C++ exception.
 | 
						|
/// @param ignoreIt unused parameter that allows function to match implied
 | 
						|
///        generated function contract.
 | 
						|
extern "C"
 | 
						|
void throwCppException (int32_t ignoreIt) {
 | 
						|
    throw(OurCppRunException("thrown by throwCppException(...)"));
 | 
						|
}
 | 
						|
 | 
						|
typedef void (*OurExceptionThrowFunctType) (int32_t typeToThrow);
 | 
						|
 | 
						|
/// This is a test harness which runs test by executing generated 
 | 
						|
/// function with a type info type to throw. Harness wraps the excecution 
 | 
						|
/// of generated function in a C++ try catch clause.
 | 
						|
/// @param engine execution engine to use for executing generated function.
 | 
						|
///        This demo program expects this to be a JIT instance for demo
 | 
						|
///        purposes.
 | 
						|
/// @param function generated test function to run
 | 
						|
/// @param typeToThrow type info type of generated exception to throw, or
 | 
						|
///        indicator to cause foreign exception to be thrown.
 | 
						|
static
 | 
						|
void runExceptionThrow(llvm::ExecutionEngine* engine, 
 | 
						|
                       llvm::Function* function, 
 | 
						|
                       int32_t typeToThrow) {
 | 
						|
 | 
						|
    // Find test's function pointer
 | 
						|
    OurExceptionThrowFunctType functPtr = 
 | 
						|
          reinterpret_cast<OurExceptionThrowFunctType>(
 | 
						|
              reinterpret_cast<intptr_t>(
 | 
						|
                  engine->getPointerToFunction(function)
 | 
						|
              )
 | 
						|
          );
 | 
						|
 | 
						|
    try {
 | 
						|
        // Run test
 | 
						|
        (*functPtr)(typeToThrow);
 | 
						|
    }
 | 
						|
    catch (OurCppRunException exc) {
 | 
						|
        // Catch foreign C++ exception
 | 
						|
        fprintf(stderr,
 | 
						|
                "\nrunExceptionThrow(...):In C++ catch OurCppRunException "
 | 
						|
                    "with reason: %s.\n", 
 | 
						|
                exc.what());
 | 
						|
    }
 | 
						|
    catch (...) {
 | 
						|
        // Catch all exceptions including our generated ones. I'm not sure
 | 
						|
        // why this latter functionality should work, as it seems that
 | 
						|
        // our exceptions should be foreign to C++ (the _Unwind_Exception::
 | 
						|
        // exception_class should be different from the one used by C++), and
 | 
						|
        // therefore C++ should ignore the generated exceptions. 
 | 
						|
 | 
						|
        fprintf(stderr,
 | 
						|
                "\nrunExceptionThrow(...):In C++ catch all.\n");
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
//
 | 
						|
// End test functions
 | 
						|
//
 | 
						|
 | 
						|
/// This initialization routine creates type info globals and 
 | 
						|
/// adds external function declarations to module.
 | 
						|
/// @param numTypeInfos number of linear type info associated type info types
 | 
						|
///        to create as GlobalVariable instances, starting with the value 1.
 | 
						|
/// @param module code for module instance
 | 
						|
/// @param builder builder instance
 | 
						|
static void createStandardUtilityFunctions(unsigned numTypeInfos,
 | 
						|
                                           llvm::Module& module, 
 | 
						|
                                           llvm::IRBuilder<>& builder) {
 | 
						|
 | 
						|
    llvm::LLVMContext& context = module.getContext();
 | 
						|
 | 
						|
    // Exception initializations
 | 
						|
 | 
						|
    // Setup exception catch state
 | 
						|
    ourExceptionNotThrownState = 
 | 
						|
                    llvm::ConstantInt::get(llvm::Type::getInt8Ty(context), 0),
 | 
						|
    ourExceptionThrownState = 
 | 
						|
                    llvm::ConstantInt::get(llvm::Type::getInt8Ty(context), 1),
 | 
						|
    ourExceptionCaughtState = 
 | 
						|
                    llvm::ConstantInt::get(llvm::Type::getInt8Ty(context), 2),
 | 
						|
 | 
						|
 | 
						|
    // Create our type info type
 | 
						|
    ourTypeInfoType = llvm::StructType::get(context, 
 | 
						|
                                            builder.getInt32Ty(), 
 | 
						|
                                            NULL);
 | 
						|
 | 
						|
    // Create OurException type
 | 
						|
    ourExceptionType = llvm::StructType::get(context, 
 | 
						|
                                             ourTypeInfoType,
 | 
						|
                                             NULL);
 | 
						|
 | 
						|
    // Create portion of _Unwind_Exception type
 | 
						|
    //
 | 
						|
    // Note: Declaring only a portion of the _Unwind_Exception struct.
 | 
						|
    //       Does this cause problems?
 | 
						|
    ourUnwindExceptionType = llvm::StructType::get(context, 
 | 
						|
                                                   builder.getInt64Ty(),
 | 
						|
                                                   NULL);
 | 
						|
    struct OurBaseException_t dummyException;
 | 
						|
 | 
						|
    // Calculate offset of OurException::unwindException member.
 | 
						|
    ourBaseFromUnwindOffset = ((uintptr_t) &dummyException) - 
 | 
						|
                           ((uintptr_t) &(dummyException.unwindException));
 | 
						|
 | 
						|
#ifdef DEBUG
 | 
						|
    fprintf(stderr,
 | 
						|
            "createStandardUtilityFunctions(...):ourBaseFromUnwindOffset "
 | 
						|
                "= %lld, sizeof(struct OurBaseException_t) - "
 | 
						|
                "sizeof(struct _Unwind_Exception) = %lu.\n",
 | 
						|
            ourBaseFromUnwindOffset,
 | 
						|
            sizeof(struct OurBaseException_t) - 
 | 
						|
                sizeof(struct _Unwind_Exception));
 | 
						|
#endif
 | 
						|
 | 
						|
    size_t numChars = sizeof(ourBaseExcpClassChars) / sizeof(char);
 | 
						|
 | 
						|
    // Create our _Unwind_Exception::exception_class value
 | 
						|
    ourBaseExceptionClass = genClass(ourBaseExcpClassChars, numChars);
 | 
						|
 | 
						|
    // Type infos
 | 
						|
 | 
						|
    std::string baseStr = "typeInfo", typeInfoName;
 | 
						|
    std::ostringstream typeInfoNameBuilder;
 | 
						|
    std::vector<llvm::Constant*> structVals;
 | 
						|
    
 | 
						|
    llvm::Constant *nextStruct;
 | 
						|
    llvm::GlobalVariable* nextGlobal = NULL;
 | 
						|
 | 
						|
    // Generate each type info
 | 
						|
    //
 | 
						|
    // Note: First type info is not used.
 | 
						|
    for (unsigned i = 0; i <= numTypeInfos; ++i) {
 | 
						|
        structVals.clear();
 | 
						|
        structVals.push_back(llvm::ConstantInt::get(builder.getInt32Ty(), i));
 | 
						|
        nextStruct = llvm::ConstantStruct::get(ourTypeInfoType, structVals);
 | 
						|
 | 
						|
        typeInfoNameBuilder.str("");
 | 
						|
        typeInfoNameBuilder << baseStr << i;
 | 
						|
        typeInfoName = typeInfoNameBuilder.str();
 | 
						|
 | 
						|
        // Note: Does not seem to work without allocation
 | 
						|
        nextGlobal = 
 | 
						|
            new llvm::GlobalVariable(module, 
 | 
						|
                                     ourTypeInfoType, 
 | 
						|
                                     true, 
 | 
						|
                                     llvm::GlobalValue::ExternalLinkage, 
 | 
						|
                                     nextStruct, 
 | 
						|
                                     typeInfoName);
 | 
						|
 | 
						|
        ourTypeInfoNames.push_back(typeInfoName);
 | 
						|
        ourTypeInfoNamesIndex[i] = typeInfoName;
 | 
						|
    }
 | 
						|
 | 
						|
    ArgNames argNames;
 | 
						|
    ArgTypes argTypes;
 | 
						|
    llvm::Function* funct = NULL;
 | 
						|
 | 
						|
    // print32Int
 | 
						|
 | 
						|
    const llvm::Type* retType = builder.getVoidTy();
 | 
						|
 | 
						|
    argTypes.clear();
 | 
						|
    argTypes.push_back(builder.getInt32Ty());
 | 
						|
    argTypes.push_back(builder.getInt8Ty()->getPointerTo());
 | 
						|
 | 
						|
    argNames.clear();
 | 
						|
 | 
						|
    createFunction(module, 
 | 
						|
                   retType, 
 | 
						|
                   argTypes, 
 | 
						|
                   argNames, 
 | 
						|
                   "print32Int", 
 | 
						|
                   llvm::Function::ExternalLinkage, 
 | 
						|
                   true, 
 | 
						|
                   false);
 | 
						|
 | 
						|
    // print64Int
 | 
						|
 | 
						|
    retType = builder.getVoidTy();
 | 
						|
 | 
						|
    argTypes.clear();
 | 
						|
    argTypes.push_back(builder.getInt64Ty());
 | 
						|
    argTypes.push_back(builder.getInt8Ty()->getPointerTo());
 | 
						|
 | 
						|
    argNames.clear();
 | 
						|
 | 
						|
    createFunction(module, 
 | 
						|
                   retType, 
 | 
						|
                   argTypes, 
 | 
						|
                   argNames, 
 | 
						|
                   "print64Int", 
 | 
						|
                   llvm::Function::ExternalLinkage, 
 | 
						|
                   true, 
 | 
						|
                   false);
 | 
						|
 | 
						|
    // printStr
 | 
						|
 | 
						|
    retType = builder.getVoidTy();
 | 
						|
 | 
						|
    argTypes.clear();
 | 
						|
    argTypes.push_back(builder.getInt8Ty()->getPointerTo());
 | 
						|
 | 
						|
    argNames.clear();
 | 
						|
 | 
						|
    createFunction(module, 
 | 
						|
                   retType, 
 | 
						|
                   argTypes, 
 | 
						|
                   argNames, 
 | 
						|
                   "printStr", 
 | 
						|
                   llvm::Function::ExternalLinkage, 
 | 
						|
                   true, 
 | 
						|
                   false);
 | 
						|
 | 
						|
    // throwCppException
 | 
						|
 | 
						|
    retType = builder.getVoidTy();
 | 
						|
 | 
						|
    argTypes.clear();
 | 
						|
    argTypes.push_back(builder.getInt32Ty());
 | 
						|
 | 
						|
    argNames.clear();
 | 
						|
 | 
						|
    createFunction(module, 
 | 
						|
                   retType, 
 | 
						|
                   argTypes, 
 | 
						|
                   argNames, 
 | 
						|
                   "throwCppException", 
 | 
						|
                   llvm::Function::ExternalLinkage, 
 | 
						|
                   true, 
 | 
						|
                   false);
 | 
						|
 | 
						|
    // deleteOurException
 | 
						|
 | 
						|
    retType = builder.getVoidTy();
 | 
						|
 | 
						|
    argTypes.clear();
 | 
						|
    argTypes.push_back(builder.getInt8Ty()->getPointerTo());
 | 
						|
 | 
						|
    argNames.clear();
 | 
						|
 | 
						|
    createFunction(module, 
 | 
						|
                   retType, 
 | 
						|
                   argTypes, 
 | 
						|
                   argNames, 
 | 
						|
                   "deleteOurException", 
 | 
						|
                   llvm::Function::ExternalLinkage, 
 | 
						|
                   true, 
 | 
						|
                   false);
 | 
						|
 | 
						|
    // createOurException
 | 
						|
 | 
						|
    retType = builder.getInt8Ty()->getPointerTo();
 | 
						|
 | 
						|
    argTypes.clear();
 | 
						|
    argTypes.push_back(builder.getInt32Ty());
 | 
						|
 | 
						|
    argNames.clear();
 | 
						|
 | 
						|
    createFunction(module, 
 | 
						|
                   retType, 
 | 
						|
                   argTypes, 
 | 
						|
                   argNames, 
 | 
						|
                   "createOurException", 
 | 
						|
                   llvm::Function::ExternalLinkage, 
 | 
						|
                   true, 
 | 
						|
                   false);
 | 
						|
 | 
						|
    // _Unwind_RaiseException
 | 
						|
 | 
						|
    retType = builder.getInt32Ty();
 | 
						|
 | 
						|
    argTypes.clear();
 | 
						|
    argTypes.push_back(builder.getInt8Ty()->getPointerTo());
 | 
						|
 | 
						|
    argNames.clear();
 | 
						|
 | 
						|
    funct = createFunction(module, 
 | 
						|
                           retType, 
 | 
						|
                           argTypes, 
 | 
						|
                           argNames, 
 | 
						|
                           "_Unwind_RaiseException", 
 | 
						|
                           llvm::Function::ExternalLinkage, 
 | 
						|
                           true, 
 | 
						|
                           false);
 | 
						|
 | 
						|
    funct->addFnAttr(llvm::Attribute::NoReturn);
 | 
						|
 | 
						|
    // _Unwind_Resume
 | 
						|
 | 
						|
    retType = builder.getInt32Ty();
 | 
						|
 | 
						|
    argTypes.clear();
 | 
						|
    argTypes.push_back(builder.getInt8Ty()->getPointerTo());
 | 
						|
 | 
						|
    argNames.clear();
 | 
						|
 | 
						|
    funct = createFunction(module, 
 | 
						|
                           retType, 
 | 
						|
                           argTypes, 
 | 
						|
                           argNames, 
 | 
						|
                           "_Unwind_Resume", 
 | 
						|
                           llvm::Function::ExternalLinkage, 
 | 
						|
                           true, 
 | 
						|
                           false);
 | 
						|
 | 
						|
    funct->addFnAttr(llvm::Attribute::NoReturn);
 | 
						|
 | 
						|
    // ourPersonality
 | 
						|
 | 
						|
    retType = builder.getInt32Ty();
 | 
						|
 | 
						|
    argTypes.clear();
 | 
						|
    argTypes.push_back(builder.getInt32Ty());
 | 
						|
    argTypes.push_back(builder.getInt32Ty());
 | 
						|
    argTypes.push_back(builder.getInt64Ty());
 | 
						|
    argTypes.push_back(builder.getInt8Ty()->getPointerTo());
 | 
						|
    argTypes.push_back(builder.getInt8Ty()->getPointerTo());
 | 
						|
 | 
						|
    argNames.clear();
 | 
						|
 | 
						|
    createFunction(module, 
 | 
						|
                   retType, 
 | 
						|
                   argTypes, 
 | 
						|
                   argNames, 
 | 
						|
                   "ourPersonality", 
 | 
						|
                   llvm::Function::ExternalLinkage, 
 | 
						|
                   true, 
 | 
						|
                   false);
 | 
						|
 | 
						|
    // llvm.eh.selector intrinsic
 | 
						|
 | 
						|
    getDeclaration(&module, llvm::Intrinsic::eh_selector);
 | 
						|
 | 
						|
    // llvm.eh.exception intrinsic
 | 
						|
 | 
						|
    getDeclaration(&module, llvm::Intrinsic::eh_exception);
 | 
						|
 | 
						|
    // llvm.eh.typeid.for intrinsic
 | 
						|
 | 
						|
    getDeclaration(&module, llvm::Intrinsic::eh_typeid_for);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
//===---------------------------------------------------------------------===//
 | 
						|
// Main test driver code.
 | 
						|
//===---------------------------------------------------------------------===//
 | 
						|
 | 
						|
/// Demo main routine which takes the type info types to throw. A test will
 | 
						|
/// be run for each given type info type. While type info types with the value 
 | 
						|
/// of -1 will trigger a foreign C++ exception to be thrown; type info types
 | 
						|
/// <= 6 and >= 1 will be caught by test functions; and type info types > 6
 | 
						|
/// will result in exceptions which pass through to the test harness. All other
 | 
						|
/// type info types are not supported and could cause a crash.
 | 
						|
int main(int argc, char* argv[]) {
 | 
						|
    if (argc == 1) {
 | 
						|
        fprintf(stderr,
 | 
						|
                "\nUsage: ExceptionDemo <exception type to throw> "
 | 
						|
                    "[<type 2>...<type n>].\n"
 | 
						|
                    "   Each type must have the value of 1 - 6 for "
 | 
						|
                    "generated exceptions to be caught;\n"
 | 
						|
                    "   the value -1 for foreign C++ exceptions to be "
 | 
						|
                    "generated and thrown;\n"
 | 
						|
                    "   or the values > 6 for exceptions to be ignored.\n"
 | 
						|
                    "\nTry: ExceptionDemo 2 3 7 -1\n"
 | 
						|
                    "   for a full test.\n\n");
 | 
						|
        return(0);
 | 
						|
    }
 | 
						|
 | 
						|
    // If not set, exception handling will not be turned on
 | 
						|
    llvm::JITExceptionHandling = true;
 | 
						|
 | 
						|
    llvm::InitializeNativeTarget();
 | 
						|
    llvm::LLVMContext& context = llvm::getGlobalContext();
 | 
						|
    llvm::IRBuilder<> theBuilder(context);
 | 
						|
 | 
						|
    // Make the module, which holds all the code.
 | 
						|
    llvm::Module* module = new llvm::Module("my cool jit", context);
 | 
						|
 | 
						|
    // Build engine with JIT
 | 
						|
    llvm::EngineBuilder factory(module);
 | 
						|
    factory.setEngineKind(llvm::EngineKind::JIT);
 | 
						|
    factory.setAllocateGVsWithCode(false);
 | 
						|
    llvm::ExecutionEngine* executionEngine = factory.create();
 | 
						|
 | 
						|
    {
 | 
						|
        llvm::FunctionPassManager fpm(module);
 | 
						|
 | 
						|
        // Set up the optimizer pipeline.  
 | 
						|
        // Start with registering info about how the
 | 
						|
        // target lays out data structures.
 | 
						|
        fpm.add(new llvm::TargetData(*executionEngine->getTargetData()));
 | 
						|
 | 
						|
        // Optimizations turned on
 | 
						|
#ifdef ADD_OPT_PASSES
 | 
						|
 | 
						|
        // Basic AliasAnslysis support for GVN.
 | 
						|
        fpm.add(llvm::createBasicAliasAnalysisPass());
 | 
						|
 | 
						|
        // Promote allocas to registers.
 | 
						|
        fpm.add(llvm::createPromoteMemoryToRegisterPass());
 | 
						|
 | 
						|
        // Do simple "peephole" optimizations and bit-twiddling optzns.
 | 
						|
        fpm.add(llvm::createInstructionCombiningPass());
 | 
						|
 | 
						|
        // Reassociate expressions.
 | 
						|
        fpm.add(llvm::createReassociatePass());
 | 
						|
 | 
						|
        // Eliminate Common SubExpressions.
 | 
						|
        fpm.add(llvm::createGVNPass());
 | 
						|
 | 
						|
        // Simplify the control flow graph (deleting unreachable 
 | 
						|
        // blocks, etc).
 | 
						|
        fpm.add(llvm::createCFGSimplificationPass());
 | 
						|
#endif  // ADD_OPT_PASSES
 | 
						|
 | 
						|
        fpm.doInitialization();
 | 
						|
 | 
						|
        // Generate test code using function throwCppException(...) as
 | 
						|
        // the function which throws foreign exceptions.
 | 
						|
        llvm::Function* toRun = 
 | 
						|
                          createUnwindExceptionTest(*module, 
 | 
						|
                                                    theBuilder, 
 | 
						|
                                                    fpm,
 | 
						|
                                                    "throwCppException");
 | 
						|
 | 
						|
        fprintf(stderr, "\nBegin module dump:\n\n");
 | 
						|
 | 
						|
        module->dump();
 | 
						|
 | 
						|
        fprintf(stderr, "\nEnd module dump:\n");
 | 
						|
 | 
						|
        fprintf(stderr, "\n\nBegin Test:\n");
 | 
						|
 | 
						|
        for (int i = 1; i < argc; ++i) {
 | 
						|
            // Run test for each argument whose value is the exception
 | 
						|
            // type to throw.
 | 
						|
            runExceptionThrow(executionEngine, 
 | 
						|
                              toRun, 
 | 
						|
                              (unsigned) strtoul(argv[i], NULL, 10));
 | 
						|
        }
 | 
						|
 | 
						|
        fprintf(stderr, "\nEnd Test:\n\n");
 | 
						|
    } 
 | 
						|
 | 
						|
    delete executionEngine;
 | 
						|
  
 | 
						|
    return 0;
 | 
						|
}
 | 
						|
 |