[PowerPC] fix lowering of SPILL_CRBIT on pwr9 and pwr10 (llvm#146424)

If a copy exists between creation of a crbit and a spill, machine-cp
may delete the copy since it seems unaware of the relation between a cr
and crbit. A fix was previously made for the generic ppc64 lowering. It
should be applied to the pwr9 and pwr10 variants too.

Likewise, relax and extend the pwr8 test to verify pwr9 and pwr10
codegen too.

This fixes llvm#143989.

(cherry picked from commit 5f86456)

Author: pmur

llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp

@@ -1102,13 +1102,20 @@ void PPCRegisterInfo::lowerCRBitSpilling(MachineBasicBlock::iterator II,
     SpillsKnownBit = true;
     break;
   default:
+    // When spilling a CR bit, the super register may not be explicitly defined
+    // (i.e. it can be defined by a CR-logical that only defines the subreg) so
+    // we state that the CR field is undef. Also, in order to preserve the kill
+    // flag on the CR bit, we add it as an implicit use.
+
     // On Power10, we can use SETNBC to spill all CR bits. SETNBC will set all
     // bits (specifically, it produces a -1 if the CR bit is set). Ultimately,
     // the bit that is of importance to us is bit 32 (bit 0 of a 32-bit
     // register), and SETNBC will set this.
     if (Subtarget.isISA3_1()) {
       BuildMI(MBB, II, dl, TII.get(LP64 ? PPC::SETNBC8 : PPC::SETNBC), Reg)
-          .addReg(SrcReg, RegState::Undef);
+          .addReg(SrcReg, RegState::Undef)
+          .addReg(SrcReg, RegState::Implicit |
+                              getKillRegState(MI.getOperand(0).isKill()));
       break;
     }
 
@@ -1122,16 +1129,14 @@ void PPCRegisterInfo::lowerCRBitSpilling(MachineBasicBlock::iterator II,
           SrcReg == PPC::CR4LT || SrcReg == PPC::CR5LT ||
           SrcReg == PPC::CR6LT || SrcReg == PPC::CR7LT) {
         BuildMI(MBB, II, dl, TII.get(LP64 ? PPC::SETB8 : PPC::SETB), Reg)
-          .addReg(getCRFromCRBit(SrcReg), RegState::Undef);
+            .addReg(getCRFromCRBit(SrcReg), RegState::Undef)
+            .addReg(SrcReg, RegState::Implicit |
+                                getKillRegState(MI.getOperand(0).isKill()));
         break;
       }
     }
 
     // We need to move the CR field that contains the CR bit we are spilling.
-    // The super register may not be explicitly defined (i.e. it can be defined
-    // by a CR-logical that only defines the subreg) so we state that the CR
-    // field is undef. Also, in order to preserve the kill flag on the CR bit,
-    // we add it as an implicit use.
     BuildMI(MBB, II, dl, TII.get(LP64 ? PPC::MFOCRF8 : PPC::MFOCRF), Reg)
       .addReg(getCRFromCRBit(SrcReg), RegState::Undef)
       .addReg(SrcReg,

llvm/test/CodeGen/PowerPC/NoCRFieldRedefWhenSpillingCRBIT.mir

@@ -1,6 +1,12 @@
 # RUN: llc -mcpu=pwr8 -mtriple=powerpc64le-unknown-linux-gnu -start-after \
 # RUN:   virtregrewriter -ppc-asm-full-reg-names -verify-machineinstrs %s \
 # RUN:   -o - | FileCheck %s
+# RUN: llc -mcpu=pwr9 -mtriple=powerpc64le-unknown-linux-gnu -start-after \
+# RUN:   virtregrewriter -ppc-asm-full-reg-names -verify-machineinstrs %s \
+# RUN:   -o - | FileCheck %s
+# RUN: llc -mcpu=pwr10 -mtriple=powerpc64le-unknown-linux-gnu -start-after \
+# RUN:   virtregrewriter -ppc-asm-full-reg-names -verify-machineinstrs %s \
+# RUN:   -o - | FileCheck %s
 
 --- |
   ; ModuleID = 'a.ll'
@@ -30,7 +36,7 @@
   ; Function Attrs: nounwind
   declare void @llvm.stackprotector(ptr, ptr) #1
 
-  attributes #0 = { nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "frame-pointer"="none" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="ppc64le" "target-features"="+altivec,+bpermd,+crypto,+direct-move,+extdiv,+htm,+power8-vector,+vsx,-power9-vector" "unsafe-fp-math"="false" "use-soft-float"="false" }
+  attributes #0 = { nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "frame-pointer"="none" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
   attributes #1 = { nounwind }
 
   !llvm.ident = !{!0}