From 396c7a932307337e252f28b2f3b3426a4eeb9385 Mon Sep 17 00:00:00 2001
From: Bruno Cardoso Lopes <bruno.cardoso@gmail.com>
Date: Sat, 14 Oct 2017 19:31:03 +0000
Subject: [PATCH] Revert "[AArch64][RegisterBankInfo] Use the statically
 computed mappings for COPY"

This reverts commit r315781, breaks:
http://green.lab.llvm.org/green/job/Compiler_Verifiers_GlobalISEL/9882

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315823 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/AArch64/AArch64RegisterBankInfo.cpp | 36 +++-----------------------
 1 file changed, 4 insertions(+), 32 deletions(-)

diff --git a/lib/Target/AArch64/AArch64RegisterBankInfo.cpp b/lib/Target/AArch64/AArch64RegisterBankInfo.cpp
index 4406ceeaddd..3c505fcec16 100644
--- a/lib/Target/AArch64/AArch64RegisterBankInfo.cpp
+++ b/lib/Target/AArch64/AArch64RegisterBankInfo.cpp
@@ -415,10 +415,12 @@ AArch64RegisterBankInfo::getSameKindOfOperandsMapping(
 const RegisterBankInfo::InstructionMapping &
 AArch64RegisterBankInfo::getInstrMapping(const MachineInstr &MI) const {
   const unsigned Opc = MI.getOpcode();
+  const MachineFunction &MF = *MI.getParent()->getParent();
+  const MachineRegisterInfo &MRI = MF.getRegInfo();
 
   // Try the default logic for non-generic instructions that are either copies
   // or already have some operands assigned to banks.
-  if ((Opc != TargetOpcode::COPY && !isPreISelGenericOpcode(Opc)) ||
+  if (!isPreISelGenericOpcode(Opc) ||
       Opc == TargetOpcode::G_PHI) {
     const RegisterBankInfo::InstructionMapping &Mapping =
         getInstrMappingImpl(MI);
@@ -426,11 +428,6 @@ AArch64RegisterBankInfo::getInstrMapping(const MachineInstr &MI) const {
       return Mapping;
   }
 
-  const MachineFunction &MF = *MI.getParent()->getParent();
-  const MachineRegisterInfo &MRI = MF.getRegInfo();
-  const TargetSubtargetInfo &STI = MF.getSubtarget();
-  const TargetRegisterInfo &TRI = *STI.getRegisterInfo();
-
   switch (Opc) {
     // G_{F|S|U}REM are not listed because they are not legal.
     // Arithmetic ops.
@@ -454,30 +451,6 @@ AArch64RegisterBankInfo::getInstrMapping(const MachineInstr &MI) const {
   case TargetOpcode::G_FMUL:
   case TargetOpcode::G_FDIV:
     return getSameKindOfOperandsMapping(MI);
-  case TargetOpcode::COPY: {
-    unsigned DstReg = MI.getOperand(0).getReg();
-    unsigned SrcReg = MI.getOperand(1).getReg();
-    if (TargetRegisterInfo::isPhysicalRegister(DstReg) ||
-        TargetRegisterInfo::isPhysicalRegister(SrcReg)) {
-      const RegisterBank *DstRB = getRegBank(DstReg, MRI, TRI);
-      const RegisterBank *SrcRB = getRegBank(SrcReg, MRI, TRI);
-      if (!DstRB)
-        DstRB = SrcRB;
-      else if (!SrcRB)
-        SrcRB = DstRB;
-      // If both RB are null that means both registers are generic.
-      // We shouldn't be here.
-      assert(DstRB && SrcRB && "Both RegBank were nullptr");
-      unsigned Size = getSizeInBits(DstReg, MRI, TRI);
-      return getInstructionMapping(
-          DefaultMappingID, copyCost(*DstRB, *SrcRB, Size),
-          getCopyMapping(DstRB->getID(), SrcRB->getID(), Size),
-          // We only care about the mapping of the destination.
-          /*NumOperands*/ 1);
-    }
-    // Both registers are generic, use G_BITCAST.
-    LLVM_FALLTHROUGH;
-  }
   case TargetOpcode::G_BITCAST: {
     LLT DstTy = MRI.getType(MI.getOperand(0).getReg());
     LLT SrcTy = MRI.getType(MI.getOperand(1).getReg());
@@ -491,8 +464,7 @@ AArch64RegisterBankInfo::getInstrMapping(const MachineInstr &MI) const {
     return getInstructionMapping(
         DefaultMappingID, copyCost(DstRB, SrcRB, Size),
         getCopyMapping(DstRB.getID(), SrcRB.getID(), Size),
-        // We only care about the mapping of the destination for COPY.
-        /*NumOperands*/ Opc == TargetOpcode::G_BITCAST ? 2 : 1);
+        /*NumOperands*/ 2);
   }
   default:
     break;
-- 
2.11.0