[GlobalISel] Make the InstructionSelector instance non-const, allowing state to be maintained.

Currently we can't keep any state in the selector object that we get from
subtarget. As a result we have to plumb through all our variables through
multiple functions. This change makes it non-const and adds a virtual init()
method to allow further state to be captured for each target.

AArch64 makes use of this in this patch to cache a call to hasFnAttribute()
which is expensive to call, and is used on each selection of G_BRCOND.

Differential Revision: https://reviews.llvm.org/D65984

llvm-svn: 368652

3 files changed, 5 insertions, 6 deletions

diff --git a/llvm/lib/Target/Mips/MipsInstructionSelector.cpp b/llvm/lib/Target/Mips/MipsInstructionSelector.cpp
index 2ac8b0fd1da..8426579720c 100644
--- a/llvm/lib/Target/Mips/MipsInstructionSelector.cpp
+++ b/llvm/lib/Target/Mips/MipsInstructionSelector.cpp
@@ -34,7 +34,7 @@ public:
   MipsInstructionSelector(const MipsTargetMachine &TM, const MipsSubtarget &STI,
                           const MipsRegisterBankInfo &RBI);
 
-  bool select(MachineInstr &I, CodeGenCoverage &CoverageInfo) const override;
+  bool select(MachineInstr &I) override;
   static const char *getName() { return DEBUG_TYPE; }
 
 private:
@@ -204,8 +204,7 @@ static unsigned selectLoadStoreOpCode(unsigned Opc, unsigned MemSizeInBytes,
   return Opc;
 }
 
-bool MipsInstructionSelector::select(MachineInstr &I,
-                                     CodeGenCoverage &CoverageInfo) const {
+bool MipsInstructionSelector::select(MachineInstr &I) {
 
   MachineBasicBlock &MBB = *I.getParent();
   MachineFunction &MF = *MBB.getParent();
@@ -232,7 +231,7 @@ bool MipsInstructionSelector::select(MachineInstr &I,
     return true;
   }
 
-  if (selectImpl(I, CoverageInfo))
+  if (selectImpl(I, *CoverageInfo))
     return true;
 
   MachineInstr *MI = nullptr;
diff --git a/llvm/lib/Target/Mips/MipsSubtarget.cpp b/llvm/lib/Target/Mips/MipsSubtarget.cpp
index d021b3d021b..137ba2129a4 100644
--- a/llvm/lib/Target/Mips/MipsSubtarget.cpp
+++ b/llvm/lib/Target/Mips/MipsSubtarget.cpp
@@ -286,6 +286,6 @@ const RegisterBankInfo *MipsSubtarget::getRegBankInfo() const {
   return RegBankInfo.get();
 }
 
-const InstructionSelector *MipsSubtarget::getInstructionSelector() const {
+InstructionSelector *MipsSubtarget::getInstructionSelector() const {
   return InstSelector.get();
 }
diff --git a/llvm/lib/Target/Mips/MipsSubtarget.h b/llvm/lib/Target/Mips/MipsSubtarget.h
index aa1200579fc..412103433a6 100644
--- a/llvm/lib/Target/Mips/MipsSubtarget.h
+++ b/llvm/lib/Target/Mips/MipsSubtarget.h
@@ -391,7 +391,7 @@ public:
   const CallLowering *getCallLowering() const override;
   const LegalizerInfo *getLegalizerInfo() const override;
   const RegisterBankInfo *getRegBankInfo() const override;
-  const InstructionSelector *getInstructionSelector() const override;
+  InstructionSelector *getInstructionSelector() const override;
 };
 } // End llvm namespace