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

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,40 @@
+; RUN: not llc < %s -mtriple=i686 2>&1 | FileCheck %s -check-prefix=i686
+; RUN: llc < %s -mtriple=x86_64 | FileCheck %s -check-prefix=x86_64
+
+define dso_local i32 @main() #0 {
+; i686: error: <unknown>:0:0: requesting 64-bit offset in 32-bit immediate: main
+;
+; x86_64-LABEL: main:
+; x86_64:       # %bb.0: # %entry
+; x86_64-NEXT:    movl $4294967176, %eax # imm = 0xFFFFFF88
+; x86_64-NEXT:    subq %rax, %rsp
+; x86_64-NEXT:    .cfi_def_cfa_offset 4294967184
+; x86_64-NEXT:    movb $32, -1073741994(%rsp)
+; x86_64-NEXT:    movb $33, 2147483478(%rsp)
+; x86_64-NEXT:    movb $34, 1073741654(%rsp)
+; x86_64-NEXT:    movb $35, -170(%rsp)
+; x86_64-NEXT:    xorl %eax, %eax
+; x86_64-NEXT:    movl $4294967176, %ecx # imm = 0xFFFFFF88
+; x86_64-NEXT:    addq %rcx, %rsp
+; x86_64-NEXT:    .cfi_def_cfa_offset 8
+; x86_64-NEXT:    retq
+entry:
+  %a = alloca [1073741824 x i8], align 16
+  %b = alloca [1073741824 x i8], align 16
+  %c = alloca [1073741824 x i8], align 16
+  %d = alloca [1073741824 x i8], align 16
+
+  %arrayida = getelementptr inbounds [1073741824 x i8], ptr %a, i64 0, i64 -42
+  %arrayidb = getelementptr inbounds [1073741824 x i8], ptr %b, i64 0, i64 -42
+  %arrayidc = getelementptr inbounds [1073741824 x i8], ptr %c, i64 0, i64 -42
+  %arrayidd = getelementptr inbounds [1073741824 x i8], ptr %d, i64 0, i64 -42
+
+  store i8 32, ptr %arrayida, align 2
+  store i8 33, ptr %arrayidb, align 2
+  store i8 34, ptr %arrayidc, align 2
+  store i8 35, ptr %arrayidd, align 2
+
+  ret i32 0
+}
+
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arsenm wrote:

Functions do not have to have names. e.g. `@0`

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