[llvm] [SDAG] Intersect poison-generating flags after CSE (PR #97434)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,25 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc < %s -mtriple=aarch64 | FileCheck %s
+
+declare void @mumble(i32)
+
+define i32 @f(i32 %0) nounwind {
+; CHECK-LABEL: f:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    stp x30, x19, [sp, #-16]! // 16-byte Folded Spill
+; CHECK-NEXT:    mov w19, w0
+; CHECK-NEXT:    neg w0, w0
+; CHECK-NEXT:    bl mumble
+; CHECK-NEXT:    mov w8, #4 // =0x4
+; CHECK-NEXT:    sub w0, w8, w19
+; CHECK-NEXT:    ldp x30, x19, [sp], #16 // 16-byte Folded Reload
+; CHECK-NEXT:    ret
+  %2 = sub nuw i32 0, %0
+  call void @mumble(i32 %2)
+  %3 = sub i32 1, %0
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arsenm wrote:

Use named values in tests 

https://github.com/llvm/llvm-project/pull/97434