diff --git a/include/llvm/IR/Operator.h b/include/llvm/IR/Operator.h index 5b9bee7fc60..119156a50e0 100644 --- a/include/llvm/IR/Operator.h +++ b/include/llvm/IR/Operator.h @@ -473,6 +473,36 @@ public: }; +class PtrToIntOperator + : public ConcreteOperator { + friend class PtrToInt; + friend class ConstantExpr; + +public: + Value *getPointerOperand() { + return getOperand(0); + } + const Value *getPointerOperand() const { + return getOperand(0); + } + static unsigned getPointerOperandIndex() { + return 0U; // get index for modifying correct operand + } + + /// getPointerOperandType - Method to return the pointer operand as a + /// PointerType. + Type *getPointerOperandType() const { + return getPointerOperand()->getType(); + } + + /// getPointerAddressSpace - Method to return the address space of the + /// pointer operand. + unsigned getPointerAddressSpace() const { + return cast(getPointerOperandType())->getAddressSpace(); + } +}; + + } // End llvm namespace #endif diff --git a/include/llvm/Target/TargetLoweringObjectFile.h b/include/llvm/Target/TargetLoweringObjectFile.h index f389e1966c0..4aedd3aa31d 100644 --- a/include/llvm/Target/TargetLoweringObjectFile.h +++ b/include/llvm/Target/TargetLoweringObjectFile.h @@ -29,6 +29,7 @@ namespace llvm { class MCSymbol; class MCSymbolRefExpr; class MCStreamer; + class ConstantExpr; class GlobalValue; class TargetMachine; @@ -152,6 +153,11 @@ public: /// emitting the address in debug info. virtual const MCExpr *getDebugThreadLocalSymbol(const MCSymbol *Sym) const; + virtual const MCExpr * + getExecutableRelativeSymbol(const ConstantExpr *CE, Mangler *Mang) const { + return 0; + } + protected: virtual const MCSection * SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind, diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp index cf950f8cc75..365a73d9753 100644 --- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp +++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp @@ -1512,6 +1512,10 @@ static const MCExpr *lowerConstant(const Constant *CV, AsmPrinter &AP) { llvm_unreachable("Unknown constant value to lower!"); } + if (const MCExpr *RelocExpr = + AP.getObjFileLowering().getExecutableRelativeSymbol(CE, AP.Mang)) + return RelocExpr; + switch (CE->getOpcode()) { default: // If the code isn't optimized, there may be outstanding folding diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp index 85999a21818..431101b6eb7 100644 --- a/lib/Target/X86/X86ISelLowering.cpp +++ b/lib/Target/X86/X86ISelLowering.cpp @@ -189,6 +189,8 @@ static TargetLoweringObjectFile *createTLOF(X86TargetMachine &TM) { return new X86LinuxTargetObjectFile(); if (Subtarget->isTargetELF()) return new TargetLoweringObjectFileELF(); + if (Subtarget->isTargetWindows()) + return new X86WindowsTargetObjectFile(); if (Subtarget->isTargetCOFF()) return new TargetLoweringObjectFileCOFF(); llvm_unreachable("unknown subtarget type"); diff --git a/lib/Target/X86/X86TargetObjectFile.cpp b/lib/Target/X86/X86TargetObjectFile.cpp index 709fc972560..bc1064e17f4 100644 --- a/lib/Target/X86/X86TargetObjectFile.cpp +++ b/lib/Target/X86/X86TargetObjectFile.cpp @@ -9,6 +9,7 @@ #include "X86TargetObjectFile.h" #include "llvm/IR/Mangler.h" +#include "llvm/IR/Operator.h" #include "llvm/MC/MCContext.h" #include "llvm/MC/MCExpr.h" #include "llvm/MC/MCSectionELF.h" @@ -53,3 +54,54 @@ X86LinuxTargetObjectFile::getDebugThreadLocalSymbol( const MCSymbol *Sym) const { return MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_DTPOFF, getContext()); } + +const MCExpr * +X86WindowsTargetObjectFile::getExecutableRelativeSymbol(const ConstantExpr *CE, + Mangler *Mang) const { + // We are looking for the difference of two symbols, need a subtraction + // operation. + const SubOperator *Sub = dyn_cast(CE); + if (!Sub) + return 0; + + // Symbols must first be numbers before we can subtract them, we need to see a + // ptrtoint on both subtraction operands. + const PtrToIntOperator *SubLHS = + dyn_cast(Sub->getOperand(0)); + const PtrToIntOperator *SubRHS = + dyn_cast(Sub->getOperand(1)); + if (!SubLHS || !SubRHS) + return 0; + + // Our symbols should exist in address space zero, cowardly no-op if + // otherwise. + if (SubLHS->getPointerAddressSpace() != 0 || + SubRHS->getPointerAddressSpace() != 0) + return 0; + + // Both ptrtoint instructions must wrap global variables: + // - Only global variables are eligible for image relative relocations. + // - The subtrahend refers to the special symbol __ImageBase, a global. + const GlobalVariable *GVLHS = + dyn_cast(SubLHS->getPointerOperand()); + const GlobalVariable *GVRHS = + dyn_cast(SubRHS->getPointerOperand()); + if (!GVLHS || !GVRHS) + return 0; + + // We expect __ImageBase to be a global variable without a section, externally + // defined. + // + // It should look something like this: @__ImageBase = external constant i8 + if (GVRHS->isThreadLocal() || GVRHS->getName() != "__ImageBase" || + !GVRHS->hasExternalLinkage() || GVRHS->hasInitializer() || + GVRHS->hasSection()) + return 0; + + // An image-relative, thread-local, symbol makes no sense. + if (GVLHS->isThreadLocal()) + return 0; + + return MCSymbolRefExpr::Create( + getSymbol(*Mang, GVLHS), MCSymbolRefExpr::VK_COFF_IMGREL32, getContext()); +} diff --git a/lib/Target/X86/X86TargetObjectFile.h b/lib/Target/X86/X86TargetObjectFile.h index 79c861d2e12..5fcd0dfba67 100644 --- a/lib/Target/X86/X86TargetObjectFile.h +++ b/lib/Target/X86/X86TargetObjectFile.h @@ -41,6 +41,12 @@ namespace llvm { virtual const MCExpr *getDebugThreadLocalSymbol(const MCSymbol *Sym) const; }; + /// \brief This implementation is used for Windows targets on x86 and x86-64. + class X86WindowsTargetObjectFile : public TargetLoweringObjectFileCOFF { + virtual const MCExpr *getExecutableRelativeSymbol(const ConstantExpr *CE, + Mangler *Mang) const; + }; + } // end namespace llvm #endif diff --git a/test/MC/COFF/ir-to-imgrel.ll b/test/MC/COFF/ir-to-imgrel.ll new file mode 100644 index 00000000000..39884d2a15e --- /dev/null +++ b/test/MC/COFF/ir-to-imgrel.ll @@ -0,0 +1,6 @@ +; RUN: llc -mtriple=x86_64-pc-win32 %s -o - | FileCheck %s --check-prefix=X64 + +@__ImageBase = external global i8 + +; X64: .quad "?x@@3HA"@IMGREL32 +@"\01?x@@3HA" = global i64 sub nsw (i64 ptrtoint (i64* @"\01?x@@3HA" to i64), i64 ptrtoint (i8* @__ImageBase to i64)), align 8