[llvm] r267660 - [ppc64] fix bug in prologue that mfocrf's cr operand should be explict state instead of implicit

[Chuang-Yu Cheng via llvm-commits]

Author: cycheng
Date: Tue Apr 26 21:59:28 2016
New Revision: 267660

URL: http://llvm.org/viewvc/llvm-project?rev=267660&view=rev
Log:
[ppc64] fix bug in prologue that mfocrf's cr operand should be explict state instead of implicit

This fixes PR27414

Reviewers: kbarton mgrang tjablin

http://reviews.llvm.org/D19255

Modified:
    llvm/trunk/lib/Target/PowerPC/PPCFrameLowering.cpp
    llvm/trunk/test/CodeGen/PowerPC/crsave.ll

Modified: llvm/trunk/lib/Target/PowerPC/PPCFrameLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/PPCFrameLowering.cpp?rev=267660&r1=267659&r2=267660&view=diff
==============================================================================
--- llvm/trunk/lib/Target/PowerPC/PPCFrameLowering.cpp (original)
+++ llvm/trunk/lib/Target/PowerPC/PPCFrameLowering.cpp Tue Apr 26 21:59:28 2016
@@ -843,12 +843,15 @@ void PPCFrameLowering::emitPrologue(Mach
     // mfocrf to selectively save just those fields, because mfocrf has short
     // latency compares to mfcr.
     unsigned MfcrOpcode = PPC::MFCR8;
-    if (isELFv2ABI && MustSaveCRs.size() == 1)
+    unsigned CrState = RegState::ImplicitKill;
+    if (isELFv2ABI && MustSaveCRs.size() == 1) {
       MfcrOpcode = PPC::MFOCRF8;
+      CrState = RegState::Kill;
+    }
     MachineInstrBuilder MIB =
       BuildMI(MBB, MBBI, dl, TII.get(MfcrOpcode), TempReg);
     for (unsigned i = 0, e = MustSaveCRs.size(); i != e; ++i)
-      MIB.addReg(MustSaveCRs[i], RegState::ImplicitKill);
+      MIB.addReg(MustSaveCRs[i], CrState);
     BuildMI(MBB, MBBI, dl, TII.get(PPC::STW8))
       .addReg(TempReg, getKillRegState(true))
       .addImm(8)
@@ -865,12 +868,15 @@ void PPCFrameLowering::emitPrologue(Mach
     // mfocrf to selectively save just those fields, because mfocrf has short
     // latency compares to mfcr.
     unsigned MfcrOpcode = PPC::MFCR8;
-    if (isELFv2ABI && MustSaveCRs.size() == 1)
+    unsigned CrState = RegState::ImplicitKill;
+    if (isELFv2ABI && MustSaveCRs.size() == 1) {
       MfcrOpcode = PPC::MFOCRF8;
+      CrState = RegState::Kill;
+    }
     MachineInstrBuilder MIB =
       BuildMI(MBB, MBBI, dl, TII.get(MfcrOpcode), TempReg);
     for (unsigned i = 0, e = MustSaveCRs.size(); i != e; ++i)
-      MIB.addReg(MustSaveCRs[i], RegState::ImplicitKill);
+      MIB.addReg(MustSaveCRs[i], CrState);
   }
 
   if (HasFP)

Modified: llvm/trunk/test/CodeGen/PowerPC/crsave.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/PowerPC/crsave.ll?rev=267660&r1=267659&r2=267660&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/PowerPC/crsave.ll (original)
+++ llvm/trunk/test/CodeGen/PowerPC/crsave.ll Tue Apr 26 21:59:28 2016
@@ -1,6 +1,6 @@
 ; RUN: llc -O0 -disable-fp-elim -mtriple=powerpc-unknown-linux-gnu -mcpu=g5 < %s | FileCheck %s -check-prefix=PPC32
 ; RUN: llc -O0 -mtriple=powerpc64-unknown-linux-gnu -mcpu=g5 < %s | FileCheck %s -check-prefix=PPC64
-; RUN: llc -O0 -mtriple=powerpc64le-unknown-linux-gnu < %s | FileCheck %s -check-prefix=PPC64-ELFv2
+; RUN: llc -O0 -mtriple=powerpc64le-unknown-linux-gnu -verify-machineinstrs < %s | FileCheck %s -check-prefix=PPC64-ELFv2
 
 declare void @foo()