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Diffstat (limited to 'contrib/llvm/lib/CodeGen/FaultMaps.cpp')
-rw-r--r-- | contrib/llvm/lib/CodeGen/FaultMaps.cpp | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/contrib/llvm/lib/CodeGen/FaultMaps.cpp b/contrib/llvm/lib/CodeGen/FaultMaps.cpp new file mode 100644 index 0000000..0512ff9 --- /dev/null +++ b/contrib/llvm/lib/CodeGen/FaultMaps.cpp @@ -0,0 +1,114 @@ +//===---------------------------- FaultMaps.cpp ---------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "llvm/CodeGen/FaultMaps.h" + +#include "llvm/CodeGen/AsmPrinter.h" +#include "llvm/MC/MCContext.h" +#include "llvm/MC/MCExpr.h" +#include "llvm/MC/MCObjectFileInfo.h" +#include "llvm/MC/MCStreamer.h" +#include "llvm/Support/Debug.h" + +using namespace llvm; + +#define DEBUG_TYPE "faultmaps" + +static const int FaultMapVersion = 1; +const char *FaultMaps::WFMP = "Fault Maps: "; + +FaultMaps::FaultMaps(AsmPrinter &AP) : AP(AP) {} + +void FaultMaps::recordFaultingOp(FaultKind FaultTy, + const MCSymbol *HandlerLabel) { + MCContext &OutContext = AP.OutStreamer->getContext(); + MCSymbol *FaultingLabel = OutContext.createTempSymbol(); + + AP.OutStreamer->EmitLabel(FaultingLabel); + + const MCExpr *FaultingOffset = MCBinaryExpr::createSub( + MCSymbolRefExpr::create(FaultingLabel, OutContext), + MCSymbolRefExpr::create(AP.CurrentFnSymForSize, OutContext), OutContext); + + const MCExpr *HandlerOffset = MCBinaryExpr::createSub( + MCSymbolRefExpr::create(HandlerLabel, OutContext), + MCSymbolRefExpr::create(AP.CurrentFnSymForSize, OutContext), OutContext); + + FunctionInfos[AP.CurrentFnSym].emplace_back(FaultTy, FaultingOffset, + HandlerOffset); +} + +void FaultMaps::serializeToFaultMapSection() { + if (FunctionInfos.empty()) + return; + + MCContext &OutContext = AP.OutStreamer->getContext(); + MCStreamer &OS = *AP.OutStreamer; + + // Create the section. + MCSection *FaultMapSection = + OutContext.getObjectFileInfo()->getFaultMapSection(); + OS.SwitchSection(FaultMapSection); + + // Emit a dummy symbol to force section inclusion. + OS.EmitLabel(OutContext.getOrCreateSymbol(Twine("__LLVM_FaultMaps"))); + + DEBUG(dbgs() << "********** Fault Map Output **********\n"); + + // Header + OS.EmitIntValue(FaultMapVersion, 1); // Version. + OS.EmitIntValue(0, 1); // Reserved. + OS.EmitIntValue(0, 2); // Reserved. + + DEBUG(dbgs() << WFMP << "#functions = " << FunctionInfos.size() << "\n"); + OS.EmitIntValue(FunctionInfos.size(), 4); + + DEBUG(dbgs() << WFMP << "functions:\n"); + + for (const auto &FFI : FunctionInfos) + emitFunctionInfo(FFI.first, FFI.second); +} + +void FaultMaps::emitFunctionInfo(const MCSymbol *FnLabel, + const FunctionFaultInfos &FFI) { + MCStreamer &OS = *AP.OutStreamer; + + DEBUG(dbgs() << WFMP << " function addr: " << *FnLabel << "\n"); + OS.EmitSymbolValue(FnLabel, 8); + + DEBUG(dbgs() << WFMP << " #faulting PCs: " << FFI.size() << "\n"); + OS.EmitIntValue(FFI.size(), 4); + + OS.EmitIntValue(0, 4); // Reserved + + for (auto &Fault : FFI) { + DEBUG(dbgs() << WFMP << " fault type: " + << faultTypeToString(Fault.Kind) << "\n"); + OS.EmitIntValue(Fault.Kind, 4); + + DEBUG(dbgs() << WFMP << " faulting PC offset: " + << *Fault.FaultingOffsetExpr << "\n"); + OS.EmitValue(Fault.FaultingOffsetExpr, 4); + + DEBUG(dbgs() << WFMP << " fault handler PC offset: " + << *Fault.HandlerOffsetExpr << "\n"); + OS.EmitValue(Fault.HandlerOffsetExpr, 4); + } +} + + +const char *FaultMaps::faultTypeToString(FaultMaps::FaultKind FT) { + switch (FT) { + default: + llvm_unreachable("unhandled fault type!"); + + case FaultMaps::FaultingLoad: + return "FaultingLoad"; + } +} |