[EraVM] Add pre-commit test for Optimize copies when src is used duri…

…ng backward propagation

Signed-off-by: Vladimir Radosavljevic <[email protected]>

llvm/test/CodeGen/EraVM/machine-cp-backward-users.mir

@@ -0,0 +1,28 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 2
+# RUN: llc -x mir -run-pass machine-cp -verify-machineinstrs -compile-twice=false < %s | FileCheck %s
+
+--- |
+
+  target datalayout = "E-p:256:256-i256:256:256-S32-a:256:256"
+  target triple = "eravm"
+
+  define void @test(i256 %a, i256 %b) { ret void }
+
+...
+---
+name:            test
+tracksRegLiveness: true
+body:             |
+  bb.0:
+    liveins: $r1, $r2, $r4
+    ; CHECK-LABEL: name: test
+    ; CHECK: liveins: $r1, $r2, $r4
+    ; CHECK-NEXT: {{  $}}
+    ; CHECK-NEXT: renamable $r3 = ADDirr_s i256 1, killed renamable $r1, i256 0
+    ; CHECK-NEXT: dead $r0 = SUBrrr_v renamable $r3, renamable $r2, i256 0, implicit-def $flags
+    ; CHECK-NEXT: renamable $r1 = COPY killed renamable $r3
+    ; CHECK-NEXT: RET 0, implicit $r1
+    renamable $r3 = ADDirr_s i256 1, killed renamable $r1, i256 0
+    dead $r0 = SUBrrr_v renamable $r3, renamable $r2, i256 0, implicit-def $flags
+    renamable $r1 = COPY killed renamable $r3
+    RET 0, implicit $r1