[llvm] r227763 - [PowerPC] Add implicit ops to conditional returns in PPCEarlyReturn

[Hal Finkel]

Author: hfinkel
Date: Sun Feb  1 14:16:10 2015
New Revision: 227763

URL: http://llvm.org/viewvc/llvm-project?rev=227763&view=rev
Log:
[PowerPC] Add implicit ops to conditional returns in PPCEarlyReturn

When PPCEarlyReturn, it should really copy implicit ops from the old return
instruction to the new one. This currently does not matter much, because we run
PPCEarlyReturn very late in the pipeline (there is nothing to do DCE on
definitions of those registers). However, for completeness, we should do it
anyway.

Noticed by inspection (and there should be no functional change); thus, no
test case.

Modified:
    llvm/trunk/lib/Target/PowerPC/PPCInstrInfo.cpp

Modified: llvm/trunk/lib/Target/PowerPC/PPCInstrInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/PPCInstrInfo.cpp?rev=227763&r1=227762&r2=227763&view=diff
==============================================================================
--- llvm/trunk/lib/Target/PowerPC/PPCInstrInfo.cpp (original)
+++ llvm/trunk/lib/Target/PowerPC/PPCInstrInfo.cpp Sun Feb  1 14:16:10 2015
@@ -2150,11 +2150,14 @@ protected:
            PIE = ReturnMBB.pred_end(); PI != PIE; ++PI) {
         bool OtherReference = false, BlockChanged = false;
         for (MachineBasicBlock::iterator J = (*PI)->getLastNonDebugInstr();;) {
+          MachineInstrBuilder MIB;
           if (J->getOpcode() == PPC::B) {
             if (J->getOperand(0).getMBB() == &ReturnMBB) {
               // This is an unconditional branch to the return. Replace the
               // branch with a blr.
-              BuildMI(**PI, J, J->getDebugLoc(), TII->get(I->getOpcode()));
+              MIB =
+                BuildMI(**PI, J, J->getDebugLoc(), TII->get(I->getOpcode()));
+              MIB.copyImplicitOps(I);
               MachineBasicBlock::iterator K = J--;
               K->eraseFromParent();
               BlockChanged = true;
@@ -2165,9 +2168,10 @@ protected:
             if (J->getOperand(2).getMBB() == &ReturnMBB) {
               // This is a conditional branch to the return. Replace the branch
               // with a bclr.
-              BuildMI(**PI, J, J->getDebugLoc(), TII->get(PPC::BCCLR))
-                .addImm(J->getOperand(0).getImm())
-                .addReg(J->getOperand(1).getReg());
+              MIB = BuildMI(**PI, J, J->getDebugLoc(), TII->get(PPC::BCCLR))
+                      .addImm(J->getOperand(0).getImm())
+                      .addReg(J->getOperand(1).getReg());
+              MIB.copyImplicitOps(I);
               MachineBasicBlock::iterator K = J--;
               K->eraseFromParent();
               BlockChanged = true;
@@ -2178,10 +2182,11 @@ protected:
             if (J->getOperand(1).getMBB() == &ReturnMBB) {
               // This is a conditional branch to the return. Replace the branch
               // with a bclr.
-              BuildMI(**PI, J, J->getDebugLoc(),
-                      TII->get(J->getOpcode() == PPC::BC ?
-                               PPC::BCLR : PPC::BCLRn))
-                .addReg(J->getOperand(0).getReg());
+              MIB = BuildMI(**PI, J, J->getDebugLoc(),
+                            TII->get(J->getOpcode() == PPC::BC ?
+                                     PPC::BCLR : PPC::BCLRn))
+                      .addReg(J->getOperand(0).getReg());
+              MIB.copyImplicitOps(I);
               MachineBasicBlock::iterator K = J--;
               K->eraseFromParent();
               BlockChanged = true;