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#include <inttypes.h>
#include <stdint.h>
#include <string>
#include "LLVMJITPrivate.h"
#include "WAVM/Inline/Assert.h"
#include "WAVM/Inline/BasicTypes.h"
#include "WAVM/Logging/Logging.h"
#include "WAVM/Platform/Defines.h"
PUSH_DISABLE_WARNINGS_FOR_LLVM_HEADERS
#include <llvm/ADT/StringRef.h>
#include <llvm/ADT/iterator_range.h>
#include <llvm/DebugInfo/DIContext.h>
#include <llvm/ExecutionEngine/JITSymbol.h>
#include <llvm/Object/ObjectFile.h>
#include <llvm/Object/SymbolicFile.h>
#include <llvm/Support/Error.h>
POP_DISABLE_WARNINGS_FOR_LLVM_HEADERS
#define PRINT_SEH_TABLES 0
using namespace WAVM;
enum UnwindOpcode
{
UWOP_PUSH_NONVOL = 0,
UWOP_ALLOC_LARGE = 1,
UWOP_ALLOC_SMALL = 2,
UWOP_SET_FPREG = 3,
UWOP_SAVE_NONVOL = 4,
UWOP_SAVE_NONVOL_FAR = 5,
UWOP_SAVE_XMM128 = 6,
UWOP_SAVE_XMM128_FAR = 7,
UWOP_PUSH_MACHFRAME = 8
};
WAVM_PACKED_STRUCT(struct SEHLanguageSpecificDataEntry {
U32 startAddress;
U32 endAddress;
U32 filterOrFinallyAddress;
U32 landingPadAddress;
});
WAVM_PACKED_STRUCT(struct SEHLanguageSpecificData {
U32 numEntries;
SEHLanguageSpecificDataEntry entries[1];
});
WAVM_PACKED_STRUCT(struct UnwindInfoSuffix {
U32 exceptionHandlerAddress;
SEHLanguageSpecificData sehLSDA;
});
WAVM_PACKED_STRUCT(struct UnwindCode {
U8 codeOffset;
UnwindOpcode opcode : 4;
U8 opInfo : 4;
});
namespace UnwindInfoFlags {
enum UnwindInfoFlags : U8
{
UNW_FLAG_EHANDLER = 0x1,
UNW_FLAG_UHANDLER = 0x2,
UNW_FLAG_CHAININFO = 0x4
};
};
WAVM_PACKED_STRUCT(struct UnwindInfoPrefix {
U8 version : 3;
U8 flags : 5;
U8 sizeOfProlog;
U8 countOfCodes;
U8 frameRegister : 4;
U8 frameOffset : 4;
UnwindCode unwindCodes[1];
});
WAVM_PACKED_STRUCT(struct RuntimeFunction {
U32 beginAddress;
U32 endAddress;
union
{
U32 unwindInfoAddress;
U32 unwindData;
};
});
static const char* getUnwindRegisterName(U8 registerIndex)
{
static const char* names[] = {"rax",
"rcx",
"rdx",
"rbx",
"rsp",
"rbp",
"rsi",
"rdi",
"r8",
"r9",
"r10",
"r11",
"r12",
"r13",
"r14",
"r15"};
WAVM_ERROR_UNLESS(registerIndex < (sizeof(names) / sizeof(names[0])));
return names[registerIndex];
}
static void applyImageRelativeRelocations(const llvm::LoadedObjectInfo& loadedObject,
llvm::object::SectionRef section,
const U8* sectionCopy,
Uptr imageBaseAddress,
Uptr sehTrampolineAddress)
{
U8* sectionData = reinterpret_cast<U8*>(Uptr(loadedObject.getSectionLoadAddress(section)));
for(auto relocIt : section.relocations())
{
// Only handle type 3 (IMAGE_REL_AMD64_ADDR32NB).
if(relocIt.getType() == 3)
{
const auto symbol = relocIt.getSymbol();
U64 symbolAddress;
#if LLVM_VERSION_MAJOR >= 11
auto maybeFlags = symbol->getFlags();
if(maybeFlags && *maybeFlags & llvm::object::SymbolRef::SF_Undefined)
#else
if(symbol->getFlags() & llvm::object::SymbolRef::SF_Undefined)
#endif
{
// Resolve __CxxFrameHandler3 to the trampoline previously created in the image's
// 32-bit address space.
const std::string symbolName = cantFail(symbol->getName()).str();
if(symbolName == "__CxxFrameHandler3") { symbolAddress = sehTrampolineAddress; }
else
{
llvm::JITSymbol resolvedSymbol
= LLVMJIT::resolveJITImport(cantFail(symbol->getName()));
symbolAddress = U64(cantFail(resolvedSymbol.getAddress()));
}
}
else
{
const llvm::object::section_iterator symbolSection = cantFail(symbol->getSection());
symbolAddress = (cantFail(symbol->getAddress()) - symbolSection->getAddress())
+ loadedObject.getSectionLoadAddress(*symbolSection);
}
U32* valueToRelocate = (U32*)(sectionData + relocIt.getOffset());
const U32* originalValue = (U32*)(sectionCopy + relocIt.getOffset());
const U64 relocatedValue64 = symbolAddress + *originalValue - imageBaseAddress;
WAVM_ERROR_UNLESS(relocatedValue64 <= UINT32_MAX);
*valueToRelocate = (U32)relocatedValue64;
}
}
}
void printFunctionSEH(U8* imageBase, const RuntimeFunction& function)
{
U8* unwindInfo = reinterpret_cast<U8*>(imageBase + function.unwindInfoAddress);
UnwindInfoPrefix* unwindInfoPrefix = (UnwindInfoPrefix*)unwindInfo;
Log::printf(
Log::debug, " address: 0x%04x-0x%04x\n", function.beginAddress, function.endAddress);
Log::printf(Log::debug, " unwind info:\n");
Log::printf(Log::debug, " version: %u\n", unwindInfoPrefix->version);
Log::printf(Log::debug, " flags: %x\n", unwindInfoPrefix->flags);
Log::printf(Log::debug, " prolog bytes: %u\n", unwindInfoPrefix->sizeOfProlog);
Log::printf(Log::debug,
" frame register: %s\n",
getUnwindRegisterName(unwindInfoPrefix->frameRegister));
Log::printf(Log::debug, " frame offset: 0x%x\n", unwindInfoPrefix->frameOffset * 16);
UnwindCode* const unwindCodes = unwindInfoPrefix->unwindCodes;
UnwindCode* unwindCode = unwindCodes;
if(unwindInfoPrefix->countOfCodes)
{
Log::printf(Log::debug, " prolog unwind codes:\n");
while(unwindCode < unwindCodes + unwindInfoPrefix->countOfCodes)
{
switch(unwindCode->opcode)
{
case UWOP_PUSH_NONVOL:
Log::printf(Log::debug,
" 0x%02x UWOP_PUSH_NONVOL %s\n",
unwindCode->codeOffset,
getUnwindRegisterName(unwindCode->opInfo));
++unwindCode;
break;
case UWOP_ALLOC_LARGE:
if(unwindCode->opInfo == 0)
{
Log::printf(Log::debug,
" 0x%02x UWOP_ALLOC_LARGE 0x%x\n",
unwindCode->codeOffset,
*(U16*)&unwindCode[1] * 8);
unwindCode += 2;
}
else
{
WAVM_ERROR_UNLESS(unwindCode->opInfo == 1);
Log::printf(Log::debug,
" 0x%02x UWOP_ALLOC_LARGE 0x%x\n",
unwindCode->codeOffset,
*(U32*)&unwindCode[1]);
unwindCode += 3;
}
break;
case UWOP_ALLOC_SMALL:
Log::printf(Log::debug,
" 0x%02x UWOP_ALLOC_SMALL 0x%x\n",
unwindCode->codeOffset,
unwindCode->opInfo * 8 + 8);
++unwindCode;
break;
case UWOP_SET_FPREG:
Log::printf(Log::debug, " 0x%02x UWOP_SET_FPREG\n", unwindCode->codeOffset);
++unwindCode;
break;
case UWOP_SAVE_NONVOL:
Log::printf(Log::debug,
" 0x%02x UWOP_SAVE_NONVOL %s 0x%x\n",
unwindCode->codeOffset,
getUnwindRegisterName(unwindCode->opInfo),
*(U16*)&unwindCode[1] * 8);
unwindCode += 2;
break;
case UWOP_SAVE_NONVOL_FAR:
Log::printf(Log::debug,
" 0x%02x UWOP_SAVE_NONVOL_FAR %s 0x%x\n",
unwindCode->codeOffset,
getUnwindRegisterName(unwindCode->opInfo),
*(U32*)&unwindCode[1]);
unwindCode += 3;
break;
case UWOP_SAVE_XMM128:
Log::printf(Log::debug,
" 0x%02x UWOP_SAVE_XMM128 xmm%u 0x%x\n",
unwindCode->codeOffset,
unwindCode->opInfo,
*(U16*)&unwindCode[1] * 8);
unwindCode += 2;
break;
case UWOP_SAVE_XMM128_FAR:
Log::printf(Log::debug,
" 0x%02x UWOP_SAVE_XMM128_FAR xmm%u 0x%x\n",
unwindCode->codeOffset,
unwindCode->opInfo,
*(U32*)&unwindCode[1]);
unwindCode += 3;
break;
case UWOP_PUSH_MACHFRAME:
Log::printf(Log::debug,
" 0x%02x UWOP_PUSH_MACHFRAME %u\n",
unwindCode->codeOffset,
unwindCode->opInfo);
++unwindCode;
break;
default: Errors::fatalf("Unrecognized unwind opcode: %u", unwindCode->opcode);
}
}
}
if(unwindInfoPrefix->countOfCodes & 1) { ++unwindCode; }
if((unwindInfoPrefix->flags & UnwindInfoFlags::UNW_FLAG_EHANDLER)
|| (unwindInfoPrefix->flags & UnwindInfoFlags::UNW_FLAG_UHANDLER))
{
UnwindInfoSuffix* suffix = (UnwindInfoSuffix*)unwindCode;
Log::printf(
Log::debug, " exception handler address: 0x%x\n", suffix->exceptionHandlerAddress);
for(U32 entryIndex = 0; entryIndex < suffix->sehLSDA.numEntries; ++entryIndex)
{
const SEHLanguageSpecificDataEntry& entry = suffix->sehLSDA.entries[entryIndex];
Log::printf(Log::debug, " LSDA entry %u:\n", entryIndex);
Log::printf(
Log::debug, " address: 0x%x-0x%x\n", entry.startAddress, entry.endAddress);
Log::printf(
Log::debug, " filterOrFinally address: 0x%x\n", entry.filterOrFinallyAddress);
Log::printf(Log::debug, " landing pad address: 0x%x\n", entry.landingPadAddress);
}
}
}
void LLVMJIT::processSEHTables(U8* imageBase,
const llvm::LoadedObjectInfo& loadedObject,
const llvm::object::SectionRef& pdataSection,
const U8* pdataCopy,
Uptr pdataNumBytes,
const llvm::object::SectionRef& xdataSection,
const U8* xdataCopy,
Uptr sehTrampolineAddress)
{
WAVM_ASSERT(pdataCopy);
WAVM_ASSERT(xdataCopy);
applyImageRelativeRelocations(loadedObject,
pdataSection,
pdataCopy,
reinterpret_cast<Uptr>(imageBase),
sehTrampolineAddress);
applyImageRelativeRelocations(loadedObject,
xdataSection,
xdataCopy,
reinterpret_cast<Uptr>(imageBase),
sehTrampolineAddress);
if(PRINT_SEH_TABLES)
{
Log::printf(Log::debug, "Win64 SEH function table:\n");
const RuntimeFunction* functionTable = reinterpret_cast<const RuntimeFunction*>(
Uptr(loadedObject.getSectionLoadAddress(pdataSection)));
const Uptr numFunctions = pdataNumBytes / sizeof(RuntimeFunction);
for(Uptr functionIndex = 0; functionIndex < numFunctions; ++functionIndex)
{
Log::printf(Log::debug, " Function %" WAVM_PRIuPTR "\n", functionIndex);
printFunctionSEH(imageBase, functionTable[functionIndex]);
}
}
}
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