[AArch64][SVE] Fix crash for DestructiveBinaryCommWithRev zero merging

[Allen]

Summary

Address more Destructive type according the review on D141471

• DestructiveUnaryPassthru and DestructiveBinaryImm always return true, don't need fix
• DestructiveTernaryCommWithRev may also return false, but now don't define FalseLanesZero in the backend codegen

llvm/lib/Target/AArch64/AArch64ExpandPseudoInsts.cpp

bool AArch64ExpandPseudo::expand_DestructiveOp(
   //
   // Create the destructive operation (if required)
   //
   MachineInstrBuilder PRFX, DOP;
   if (FalseZero) {
     // If we cannot prefix the requested instruction we'll instead emit a
     // prefixed_zeroing_mov for DestructiveBinary.
     assert((DOPRegIsUnique || DType == AArch64::DestructiveBinary ||
-            DType == AArch64::DestructiveBinaryComm) &&
+            DType == AArch64::DestructiveBinaryComm ||
+            DType == AArch64::DestructiveBinaryCommWithRev) &&
            "The destructive operand should be unique");
     assert(ElementSize != AArch64::ElementSizeNone &&
            "This instruction is unpredicated");
 
     // Merge source operand into destination register
     PRFX = BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(MovPrfxZero))
                .addReg(DstReg, RegState::Define)
                .addReg(MI.getOperand(PredIdx).getReg())
                .addReg(MI.getOperand(DOPIdx).getReg());
 
     // After the movprfx, the destructive operand is same as Dst
     DOPIdx = 0;
 
     // Create the additional LSL to zero the lanes when the DstReg is not
     // unique. Zeros the lanes in z0 that aren't active in p0 with sequence
     // movprfx z0.b, p0/z, z0.b; lsl z0.b, p0/m, z0.b, #0;
     if ((DType == AArch64::DestructiveBinary ||
-         DType == AArch64::DestructiveBinaryComm) &&
+         DType == AArch64::DestructiveBinaryComm ||
+         DType == AArch64::DestructiveBinaryCommWithRev) &&
         !DOPRegIsUnique) {
       BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(LSLZero))
           .addReg(DstReg, RegState::Define)
           .add(MI.getOperand(PredIdx))
           .addReg(DstReg)
           .addImm(0);
     }
   } else if (DstReg != MI.getOperand(DOPIdx).getReg()) {

llvm/test/CodeGen/AArch64/sve-intrinsics-int-binaryCommWithRev-merging.mir

+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
+# RUN: llc -mtriple=aarch64 -mattr=+sve -mattr=+use-experimental-zeroing-pseudos -run-pass=aarch64-expand-pseudo %s -o - | FileCheck %s
+
+# Should create an additional LSL to zero the lanes as the DstReg is not unique
+
+--- |
+  define <vscale x 4 x float> @fsub_s_zero(<vscale x 4 x i1> %pg, <vscale x 4 x float> %a){
+    %a_z = select <vscale x 4 x i1> %pg, <vscale x 4 x float> %a, <vscale x 4 x float> zeroinitializer
+    %out = call <vscale x 4 x float> @llvm.aarch64.sve.fsub.nxv4f32(<vscale x 4 x i1> %pg,
+                                                                 <vscale x 4 x float> %a_z,
+                                                                 <vscale x 4 x float> %a_z)
+    ret <vscale x 4 x float> %out
+  }
+
+  declare <vscale x 4 x float> @llvm.aarch64.sve.fsub.nxv4f32(<vscale x 4 x i1>, <vscale x 4 x float>, <vscale x 4 x float>)
+...
+---
+name:            fsub_s_zero
+alignment:       4
+tracksRegLiveness: true
+tracksDebugUserValues: true
+registers:       []
+liveins:
+  - { reg: '$p0', virtual-reg: '' }
+  - { reg: '$z0', virtual-reg: '' }
+body:             |
+  bb.0 (%ir-block.0):
+    liveins: $p0, $z0
+
+    ; CHECK-LABEL: name: fsub_s_zero
+    ; CHECK: liveins: $p0, $z0
+    ; CHECK-NEXT: {{  $}}
+    ; CHECK-NEXT: BUNDLE implicit-def $z0, implicit-def $q0, implicit-def $d0, implicit-def $s0, implicit-def $h0, implicit-def $b0, implicit-def $z0_hi, implicit $p0, implicit $z0 {
+    ; CHECK-NEXT:   $z0 = MOVPRFX_ZPzZ_S $p0, $z0
+    ; CHECK-NEXT:   $z0 = LSL_ZPmI_S renamable $p0, internal $z0, 0
+    ; CHECK-NEXT:   $z0 = FSUBR_ZPmZ_S renamable $p0, internal killed $z0, internal killed renamable $z0
+    ; CHECK-NEXT: }
+    ; CHECK-NEXT: RET undef $lr, implicit $z0
+    renamable $z0 = nnan ninf nsz arcp contract afn reassoc FSUB_ZPZZ_ZERO_S renamable $p0, killed renamable $z0, renamable $z0
+    RET_ReallyLR implicit $z0
+...