[PowerPC] fix register class after converting X-FORM instruction to D-FORM instruction

Differential Revision: https://reviews.llvm.org/D55806

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@350111 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/PowerPC/PPCInstrInfo.cpp b/lib/Target/PowerPC/PPCInstrInfo.cpp
index d26af451303b6368e0e513033860d47ffa31b104..1b9d5d2d8e0b3e028c85c08e8d67d7dbf69eff87 100644 (file)
--- a/lib/Target/PowerPC/PPCInstrInfo.cpp
+++ b/lib/Target/PowerPC/PPCInstrInfo.cpp
@@ -3438,15 +3438,20 @@ bool PPCInstrInfo::transformToImmFormFedByLI(MachineInstr &MI,
   if (III.OpNoForForwarding != III.ImmOpNo)
     swapMIOperands(MI, III.OpNoForForwarding, III.ImmOpNo);
 
-  // If the R0/X0 register is special for the original instruction and not for
-  // the new instruction (or vice versa), we need to fix up the register class.
+  // If the special R0/X0 register index are different for original instruction
+  // and new instruction, we need to fix up the register class in new
+  // instruction.
   if (!PostRA && III.ZeroIsSpecialOrig != III.ZeroIsSpecialNew) {
-    if (!III.ZeroIsSpecialOrig) {
+    if (III.ZeroIsSpecialNew) {
+      // If operand at III.ZeroIsSpecialNew is physical reg(eg: ZERO/ZERO8), no
+      // need to fix up register class.
       unsigned RegToModify = MI.getOperand(III.ZeroIsSpecialNew).getReg();
-      const TargetRegisterClass *NewRC =
-        MRI.getRegClass(RegToModify)->hasSuperClassEq(&PPC::GPRCRegClass) ?
-        &PPC::GPRC_and_GPRC_NOR0RegClass : &PPC::G8RC_and_G8RC_NOX0RegClass;
-      MRI.setRegClass(RegToModify, NewRC);
+      if (TargetRegisterInfo::isVirtualRegister(RegToModify)) {
+        const TargetRegisterClass *NewRC =
+          MRI.getRegClass(RegToModify)->hasSuperClassEq(&PPC::GPRCRegClass) ?
+          &PPC::GPRC_and_GPRC_NOR0RegClass : &PPC::G8RC_and_G8RC_NOX0RegClass;
+        MRI.setRegClass(RegToModify, NewRC);
+      }
     }
   }
   return true;

diff --git a/test/CodeGen/PowerPC/convert-rr-to-ri-instrs.mir b/test/CodeGen/PowerPC/convert-rr-to-ri-instrs.mir
index e210ec5c523eb0ecc4e9b09e8f48a33286f66fde..eb058bc9b7d8454d6525cdc47dea7ddaab3ca72d 100644 (file)
--- a/test/CodeGen/PowerPC/convert-rr-to-ri-instrs.mir
+++ b/test/CodeGen/PowerPC/convert-rr-to-ri-instrs.mir
@@ -1,5 +1,5 @@
-# RUN: llc -run-pass ppc-mi-peepholes -ppc-convert-rr-to-ri %s -o - | FileCheck %s
-# RUN: llc -start-after ppc-mi-peepholes -ppc-late-peephole %s -o - | FileCheck %s --check-prefix=CHECK-LATE
+# RUN: llc -run-pass ppc-mi-peepholes -ppc-convert-rr-to-ri %s -o - -verify-machineinstrs | FileCheck %s
+# RUN: llc -start-after ppc-mi-peepholes -ppc-late-peephole %s -o - -verify-machineinstrs | FileCheck %s --check-prefix=CHECK-LATE
 
 --- |
   ; ModuleID = 'convert-rr-to-ri-instrs.ll'