[llvm] [X86] Fix 32-bit immediate assertion and convert into backend error (PR #123872)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,17 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc < %s -mtriple=x86_64 -O=0 | FileCheck %s
+ at G = global i8 0
+
+; Regression test for #113856 - incorrect FastISel assert
+
+define dso_local i32 @main() #0 {
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RKSimon wrote:

remove `dso_local` and `#0` noise?

https://github.com/llvm/llvm-project/pull/123872