[llvm] [RISCV][VLOPT] Avoid crash when user produces scalar def (PR #120255)

[Luke Lau via llvm-commits]

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@@ -0,0 +1,21 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+# RUN: llc %s -o - -mtriple=riscv32 -mattr=+v -run-pass=riscv-vl-optimizer -verify-machineinstrs | FileCheck %s
+
+---
+name:            vec_instr_with_scalar_def
+tracksRegLiveness: true
+isSSA:           true
+body:             |
+  bb.0:
+    ; CHECK-LABEL: name: vec_instr_with_scalar_def
+    ; CHECK: [[PseudoVMNAND_MM_B8_:%[0-9]+]]:vr = PseudoVMNAND_MM_B8 $noreg, $noreg, -1, 0 /* e8 */
+    ; CHECK-NEXT: [[PseudoVCPOP_M_B1_:%[0-9]+]]:gpr = PseudoVCPOP_M_B1 killed [[PseudoVMNAND_MM_B8_]], -1, 0 /* e8 */
+    ; CHECK-NEXT: [[SLTIU:%[0-9]+]]:gpr = SLTIU killed [[PseudoVCPOP_M_B1_]], 1
+    ; CHECK-NEXT: $x10 = COPY [[SLTIU]]
+    ; CHECK-NEXT: PseudoRET implicit $x10
+    %1:vr = PseudoVMNAND_MM_B8 $noreg, $noreg, -1, 0 /* e8 */
+    %2:gpr = PseudoVCPOP_M_B1 killed %1, -1, 0 /* e8 */
+    %3:gpr = SLTIU killed %2, 1
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lukel97 wrote:

Nit, are the SLTIU and COPY needed?

https://github.com/llvm/llvm-project/pull/120255