[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 +1,81 @@
+; RUN: not llc < %s -mtriple=i686 -filetype=null 2>&1 | FileCheck %s -check-prefix=ERR-i686
+; RUN: llc < %s -mtriple=x86_64 | FileCheck %s -check-prefix=x86_64
+
+; Regression test for #121932, #113856, #106352, #69365, #25051 which are caused by
+; an incorrectly written assertion for 64-bit offsets when compiling for 32-bit X86.
+
+define i32 @main() #0 {
+; ERR-i686: error: <unknown>:0:0: Requesting 64-bit offset in 32-bit immediate
+;
+; x86_64-LABEL: main:
+; x86_64:       # %bb.0: # %entry
+; x86_64-NEXT:    movl $4294967192, %eax # imm = 0xFFFFFF98
+; x86_64-NEXT:    subq %rax, %rsp
+; x86_64-NEXT:    .cfi_def_cfa_offset 4294967200
+; x86_64-NEXT:    movabsq $3221225318, %rax # imm = 0xBFFFFF66
+; x86_64-NEXT:    movb $32, (%rsp,%rax)
+; x86_64-NEXT:    movb $33, 2147483494(%rsp)
+; x86_64-NEXT:    movb $34, 1073741670(%rsp)
+; x86_64-NEXT:    movb $35, -154(%rsp)
+; x86_64-NEXT:    xorl %eax, %eax
+; x86_64-NEXT:    movl $4294967192, %ecx # imm = 0xFFFFFF98
+; 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
+}
+
+define i32 @0() #0 {
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RKSimon wrote:

Add a comment explaining we're repeating the same test for an anonymous function

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