From b87bc95db075dae3033a3c541b55b4cb711c332c Mon Sep 17 00:00:00 2001 From: David Greene Date: Thu, 12 Nov 2009 20:55:29 +0000 Subject: [PATCH] Add hasLoadFromStackSlot and hasStoreToStackSlot to return whether a machine instruction loads or stores from/to a stack slot. Unlike isLoadFromStackSlot and isStoreFromStackSlot, the instruction may be something other than a pure load/store (e.g. it may be an arithmetic operation with a memory operand). This helps AsmPrinter determine when to print a spill/reload comment. This is only a hint since we may not be able to figure this out in all cases. As such, it should not be relied upon for correctness. Implement for X86. Return false by default for other architectures. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@87026 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/Target/TargetInstrInfo.h | 22 +++++++++++ lib/Target/X86/X86InstrInfo.cpp | 69 +++++++++++++++++++++++++++++------ lib/Target/X86/X86InstrInfo.h | 22 +++++++++++ 3 files changed, 101 insertions(+), 12 deletions(-) diff --git a/include/llvm/Target/TargetInstrInfo.h b/include/llvm/Target/TargetInstrInfo.h index b16df5c2dae..42621fe6f9f 100644 --- a/include/llvm/Target/TargetInstrInfo.h +++ b/include/llvm/Target/TargetInstrInfo.h @@ -170,6 +170,17 @@ public: int &FrameIndex) const { return 0; } + + /// hasLoadFromStackSlot - If the specified machine instruction has + /// a load from a stack slot, return true along with the FrameIndex + /// of the loaded stack slot. If not, return false. Unlike + /// isLoadFromStackSlot, this returns true for any instructions that + /// loads from the stack. This is just a hint, as some cases may be + /// missed. + virtual bool hasLoadFromStackSlot(const MachineInstr *MI, + int &FrameIndex) const { + return 0; + } /// isStoreToStackSlot - If the specified machine instruction is a direct /// store to a stack slot, return the virtual or physical register number of @@ -181,6 +192,17 @@ public: return 0; } + /// hasStoreToStackSlot - If the specified machine instruction has a + /// store to a stack slot, return true along with the FrameIndex of + /// the loaded stack slot. If not, return false. Unlike + /// isStoreToStackSlot, this returns true for any instructions that + /// loads from the stack. This is just a hint, as some cases may be + /// missed. + virtual bool hasStoreToStackSlot(const MachineInstr *MI, + int &FrameIndex) const { + return 0; + } + /// reMaterialize - Re-issue the specified 'original' instruction at the /// specific location targeting a new destination register. virtual void reMaterialize(MachineBasicBlock &MBB, diff --git a/lib/Target/X86/X86InstrInfo.cpp b/lib/Target/X86/X86InstrInfo.cpp index c7d9aaa9d54..83d1db53c97 100644 --- a/lib/Target/X86/X86InstrInfo.cpp +++ b/lib/Target/X86/X86InstrInfo.cpp @@ -26,11 +26,15 @@ #include "llvm/CodeGen/MachineInstrBuilder.h" #include "llvm/CodeGen/MachineRegisterInfo.h" #include "llvm/CodeGen/LiveVariables.h" +#include "llvm/CodeGen/PseudoSourceValue.h" #include "llvm/Support/CommandLine.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/raw_ostream.h" #include "llvm/Target/TargetOptions.h" #include "llvm/MC/MCAsmInfo.h" + +#include + using namespace llvm; static cl::opt @@ -707,6 +711,21 @@ bool X86InstrInfo::isMoveInstr(const MachineInstr& MI, } } +/// isFrameOperand - Return true and the FrameIndex if the specified +/// operand and follow operands form a reference to the stack frame. +bool X86InstrInfo::isFrameOperand(const MachineInstr *MI, unsigned int Op, + int &FrameIndex) const { + if (MI->getOperand(Op).isFI() && MI->getOperand(Op+1).isImm() && + MI->getOperand(Op+2).isReg() && MI->getOperand(Op+3).isImm() && + MI->getOperand(Op+1).getImm() == 1 && + MI->getOperand(Op+2).getReg() == 0 && + MI->getOperand(Op+3).getImm() == 0) { + FrameIndex = MI->getOperand(Op).getIndex(); + return true; + } + return false; +} + unsigned X86InstrInfo::isLoadFromStackSlot(const MachineInstr *MI, int &FrameIndex) const { switch (MI->getOpcode()) { @@ -723,19 +742,32 @@ unsigned X86InstrInfo::isLoadFromStackSlot(const MachineInstr *MI, case X86::MOVDQArm: case X86::MMX_MOVD64rm: case X86::MMX_MOVQ64rm: - if (MI->getOperand(1).isFI() && MI->getOperand(2).isImm() && - MI->getOperand(3).isReg() && MI->getOperand(4).isImm() && - MI->getOperand(2).getImm() == 1 && - MI->getOperand(3).getReg() == 0 && - MI->getOperand(4).getImm() == 0) { - FrameIndex = MI->getOperand(1).getIndex(); + if (isFrameOperand(MI, 1, FrameIndex)) { return MI->getOperand(0).getReg(); } + // Check for post-frame index elimination operations + return hasLoadFromStackSlot(MI, FrameIndex); break; } return 0; } +bool X86InstrInfo::hasLoadFromStackSlot(const MachineInstr *MI, + int &FrameIndex) const { + for (MachineInstr::mmo_iterator o = MI->memoperands_begin(), + oe = MI->memoperands_end(); + o != oe; + ++o) { + if ((*o)->isLoad() && (*o)->getValue()) + if (const FixedStackPseudoSourceValue *Value = + dyn_cast((*o)->getValue())) { + FrameIndex = Value->getFrameIndex(); + return true; + } + } + return false; +} + unsigned X86InstrInfo::isStoreToStackSlot(const MachineInstr *MI, int &FrameIndex) const { switch (MI->getOpcode()) { @@ -753,19 +785,32 @@ unsigned X86InstrInfo::isStoreToStackSlot(const MachineInstr *MI, case X86::MMX_MOVD64mr: case X86::MMX_MOVQ64mr: case X86::MMX_MOVNTQmr: - if (MI->getOperand(0).isFI() && MI->getOperand(1).isImm() && - MI->getOperand(2).isReg() && MI->getOperand(3).isImm() && - MI->getOperand(1).getImm() == 1 && - MI->getOperand(2).getReg() == 0 && - MI->getOperand(3).getImm() == 0) { - FrameIndex = MI->getOperand(0).getIndex(); + if (isFrameOperand(MI, 0, FrameIndex)) { return MI->getOperand(X86AddrNumOperands).getReg(); } + // Check for post-frame index elimination operations + return hasStoreToStackSlot(MI, FrameIndex); break; } return 0; } +bool X86InstrInfo::hasStoreToStackSlot(const MachineInstr *MI, + int &FrameIndex) const { + for (MachineInstr::mmo_iterator o = MI->memoperands_begin(), + oe = MI->memoperands_end(); + o != oe; + ++o) { + if ((*o)->isStore() && (*o)->getValue()) + if (const FixedStackPseudoSourceValue *Value = + dyn_cast((*o)->getValue())) { + FrameIndex = Value->getFrameIndex(); + return true; + } + } + return false; +} + /// regIsPICBase - Return true if register is PIC base (i.e.g defined by /// X86::MOVPC32r. static bool regIsPICBase(unsigned BaseReg, const MachineRegisterInfo &MRI) { diff --git a/lib/Target/X86/X86InstrInfo.h b/lib/Target/X86/X86InstrInfo.h index 6eb07d55eb3..c5809c9638f 100644 --- a/lib/Target/X86/X86InstrInfo.h +++ b/lib/Target/X86/X86InstrInfo.h @@ -449,8 +449,25 @@ public: unsigned &SrcSubIdx, unsigned &DstSubIdx) const; unsigned isLoadFromStackSlot(const MachineInstr *MI, int &FrameIndex) const; + + /// hasLoadFromStackSlot - If the specified machine instruction has + /// a load from a stack slot, return true along with the FrameIndex + /// of the loaded stack slot. If not, return false. Unlike + /// isLoadFromStackSlot, this returns true for any instructions that + /// loads from the stack. This is a hint only and may not catch all + /// cases. + bool hasLoadFromStackSlot(const MachineInstr *MI, int &FrameIndex) const; + unsigned isStoreToStackSlot(const MachineInstr *MI, int &FrameIndex) const; + /// hasStoreToStackSlot - If the specified machine instruction has a + /// store to a stack slot, return true along with the FrameIndex of + /// the loaded stack slot. If not, return false. Unlike + /// isStoreToStackSlot, this returns true for any instructions that + /// loads from the stack. This is a hint only and may not catch all + /// cases. + bool hasStoreToStackSlot(const MachineInstr *MI, int &FrameIndex) const; + bool isReallyTriviallyReMaterializable(const MachineInstr *MI, AliasAnalysis *AA) const; void reMaterialize(MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, @@ -610,6 +627,11 @@ private: unsigned OpNum, const SmallVectorImpl &MOs, unsigned Size, unsigned Alignment) const; + + /// isFrameOperand - Return true and the FrameIndex if the specified + /// operand and follow operands form a reference to the stack frame. + bool isFrameOperand(const MachineInstr *MI, unsigned int Op, + int &FrameIndex) const; }; } // End llvm namespace -- 2.11.0