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

[Matt Arsenault via llvm-commits]

================
@@ -965,11 +965,11 @@ X86RegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
   }
 
   if (MI.getOperand(FIOperandNum+3).isImm()) {
-    // Offset is a 32-bit integer.
-    int Imm = (int)(MI.getOperand(FIOperandNum + 3).getImm());
-    int Offset = FIOffset + Imm;
-    assert((!Is64Bit || isInt<32>((long long)FIOffset + Imm)) &&
-           "Requesting 64-bit offset in 32-bit immediate!");
+    int64_t Imm = MI.getOperand(FIOperandNum + 3).getImm();
+    int Offset = FIOffset + (int)Imm;
+    if (!Is64Bit && !isInt<32>((int64_t)FIOffset + Imm))
+      MI.emitGenericError("requesting 64-bit offset in 32-bit immediate: " +
----------------
arsenm wrote:

Avoid using the function name in the message. It should be implied and printed from the debug location of the instruction, and this won't handle anonymous functions correctly 

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