-//===-- X86AsmPrinter.h - Convert X86 LLVM code to Intel assembly ---------===//
+//===-- X86AsmPrinter.h - X86 implementation of AsmPrinter ------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file the shared super class printer that converts from our internal
-// representation of machine-dependent LLVM code to Intel and AT&T format
-// assembly language. This printer is the output mechanism used by `llc'.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
-#ifndef X86ASMPRINTER_H
-#define X86ASMPRINTER_H
+#ifndef LLVM_LIB_TARGET_X86_X86ASMPRINTER_H
+#define LLVM_LIB_TARGET_X86_X86ASMPRINTER_H
-#include "X86.h"
+#include "X86Subtarget.h"
#include "llvm/CodeGen/AsmPrinter.h"
-#include "llvm/ADT/Statistic.h"
+#include "llvm/CodeGen/StackMaps.h"
+#include "llvm/Target/TargetMachine.h"
+
+// Implemented in X86MCInstLower.cpp
+namespace {
+ class X86MCInstLower;
+}
namespace llvm {
-namespace x86 {
+class MCStreamer;
+class MCSymbol;
+
+class LLVM_LIBRARY_VISIBILITY X86AsmPrinter : public AsmPrinter {
+ const X86Subtarget *Subtarget;
+ StackMaps SM;
+
+ void GenerateExportDirective(const MCSymbol *Sym, bool IsData);
+
+ // This utility class tracks the length of a stackmap instruction's 'shadow'.
+ // It is used by the X86AsmPrinter to ensure that the stackmap shadow
+ // invariants (i.e. no other stackmaps, patchpoints, or control flow within
+ // the shadow) are met, while outputting a minimal number of NOPs for padding.
+ //
+ // To minimise the number of NOPs used, the shadow tracker counts the number
+ // of instruction bytes output since the last stackmap. Only if there are too
+ // few instruction bytes to cover the shadow are NOPs used for padding.
+ class StackMapShadowTracker {
+ public:
+ StackMapShadowTracker(TargetMachine &TM);
+ ~StackMapShadowTracker();
+ void startFunction(MachineFunction &MF);
+ void count(MCInst &Inst, const MCSubtargetInfo &STI);
+
+ // Called to signal the start of a shadow of RequiredSize bytes.
+ void reset(unsigned RequiredSize) {
+ RequiredShadowSize = RequiredSize;
+ CurrentShadowSize = 0;
+ InShadow = true;
+ }
+
+ // Called before every stackmap/patchpoint, and at the end of basic blocks,
+ // to emit any necessary padding-NOPs.
+ void emitShadowPadding(MCStreamer &OutStreamer, const MCSubtargetInfo &STI);
+ private:
+ TargetMachine &TM;
+ std::unique_ptr<MCCodeEmitter> CodeEmitter;
+ bool InShadow;
+
+ // RequiredShadowSize holds the length of the shadow specified in the most
+ // recently encountered STACKMAP instruction.
+ // CurrentShadowSize counts the number of bytes encoded since the most
+ // recently encountered STACKMAP, stopping when that number is greater than
+ // or equal to RequiredShadowSize.
+ unsigned RequiredShadowSize, CurrentShadowSize;
+ };
-extern Statistic<> EmittedInsts;
+ StackMapShadowTracker SMShadowTracker;
-struct X86SharedAsmPrinter : public AsmPrinter {
- X86SharedAsmPrinter(std::ostream &O, TargetMachine &TM)
- : AsmPrinter(O, TM), forCygwin(false), forDarwin(false) { }
+ // All instructions emitted by the X86AsmPrinter should use this helper
+ // method.
+ //
+ // This helper function invokes the SMShadowTracker on each instruction before
+ // outputting it to the OutStream. This allows the shadow tracker to minimise
+ // the number of NOPs used for stackmap padding.
+ void EmitAndCountInstruction(MCInst &Inst);
- bool doInitialization(Module &M);
- void printConstantPool(MachineConstantPool *MCP);
- bool doFinalization(Module &M);
+ void InsertStackMapShadows(MachineFunction &MF);
+ void LowerSTACKMAP(const MachineInstr &MI);
+ void LowerPATCHPOINT(const MachineInstr &MI);
- bool forCygwin;
- bool forDarwin;
+ void LowerTlsAddr(X86MCInstLower &MCInstLowering, const MachineInstr &MI);
- inline static bool isScale(const MachineOperand &MO) {
- return MO.isImmediate() &&
- (MO.getImmedValue() == 1 || MO.getImmedValue() == 2 ||
- MO.getImmedValue() == 4 || MO.getImmedValue() == 8);
+ public:
+ explicit X86AsmPrinter(TargetMachine &TM, MCStreamer &Streamer)
+ : AsmPrinter(TM, Streamer), SM(*this), SMShadowTracker(TM) {
+ Subtarget = &TM.getSubtarget<X86Subtarget>();
}
- inline static bool isMem(const MachineInstr *MI, unsigned Op) {
- if (MI->getOperand(Op).isFrameIndex()) return true;
- if (MI->getOperand(Op).isConstantPoolIndex()) return true;
- return Op+4 <= MI->getNumOperands() &&
- MI->getOperand(Op ).isRegister() && isScale(MI->getOperand(Op+1)) &&
- MI->getOperand(Op+2).isRegister() && (MI->getOperand(Op+3).isImmediate()||
- MI->getOperand(Op+3).isGlobalAddress());
+ const char *getPassName() const override {
+ return "X86 Assembly / Object Emitter";
}
- // SwitchSection - Switch to the specified section of the executable if we are
- // not already in it!
- inline static void SwitchSection(std::ostream &OS, std::string &CurSection,
- const char *NewSection) {
- if (CurSection != NewSection) {
- CurSection = NewSection;
- if (!CurSection.empty())
- OS << "\t" << NewSection << "\n";
- }
+ const X86Subtarget &getSubtarget() const { return *Subtarget; }
+
+ void EmitStartOfAsmFile(Module &M) override;
+
+ void EmitEndOfAsmFile(Module &M) override;
+
+ void EmitInstruction(const MachineInstr *MI) override;
+
+ void EmitBasicBlockEnd(const MachineBasicBlock &MBB) override {
+ SMShadowTracker.emitShadowPadding(OutStreamer, getSubtargetInfo());
}
+
+ bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
+ unsigned AsmVariant, const char *ExtraCode,
+ raw_ostream &OS) override;
+ bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
+ unsigned AsmVariant, const char *ExtraCode,
+ raw_ostream &OS) override;
+
+ /// \brief Return the symbol for the specified constant pool entry.
+ MCSymbol *GetCPISymbol(unsigned CPID) const override;
+
+ bool doInitialization(Module &M) override {
+ SMShadowTracker.reset(0);
+ SM.reset();
+ return AsmPrinter::doInitialization(M);
+ }
+
+ bool runOnMachineFunction(MachineFunction &F) override;
};
-} // end namespace x86
} // end namespace llvm
#endif