[clang] [X86] [iamcu] Fix wrong alignment value for attr (aligned) with -miamcu (PR #80401)

[via cfe-commits]

https://github.com/joyhou-hw updated https://github.com/llvm/llvm-project/pull/80401

>From 834e55dbf7ac54ad7d006866ae4da3190f2197aa Mon Sep 17 00:00:00 2001
From: houzhenyu <houzhenyu at huawei.com>
Date: Fri, 2 Feb 2024 11:21:50 +0800
Subject: [PATCH] [X86] [iamcu] Fix wrong alignment value for attr (aligned)
 with -miamcu

attribute ((aligned)) should be 4 for -miamcu.
---
 clang/lib/Basic/Targets/X86.h  | 1 +
 clang/test/Sema/attr-aligned.c | 5 +++++
 2 files changed, 6 insertions(+)

diff --git a/clang/lib/Basic/Targets/X86.h b/clang/lib/Basic/Targets/X86.h
index 1845f5a747af4..0026d8781c8fa 100644
--- a/clang/lib/Basic/Targets/X86.h
+++ b/clang/lib/Basic/Targets/X86.h
@@ -672,6 +672,7 @@ class LLVM_LIBRARY_VISIBILITY MCUX86_32TargetInfo : public X86_32TargetInfo {
   MCUX86_32TargetInfo(const llvm::Triple &Triple, const TargetOptions &Opts)
       : X86_32TargetInfo(Triple, Opts) {
     LongDoubleWidth = 64;
+    DefaultAlignForAttributeAligned = 32;
     LongDoubleFormat = &llvm::APFloat::IEEEdouble();
     resetDataLayout("e-m:e-p:32:32-p270:32:32-p271:32:32-p272:64:64-i64:32-"
                     "f64:32-f128:32-n8:16:32-a:0:32-S32");
diff --git a/clang/test/Sema/attr-aligned.c b/clang/test/Sema/attr-aligned.c
index 130840d46650d..bdd48e7268285 100644
--- a/clang/test/Sema/attr-aligned.c
+++ b/clang/test/Sema/attr-aligned.c
@@ -1,4 +1,5 @@
 // RUN: %clang_cc1 -triple x86_64-apple-darwin9 -fsyntax-only -verify %s
+// RUN: %clang_cc1 -triple i586-intel-elfiamcu -fsyntax-only -verify %s
 
 int x __attribute__((aligned(3))); // expected-error {{requested alignment is not a power of 2}}
 int y __attribute__((aligned(1ull << 33))); // expected-error {{requested alignment must be 4294967296 bytes or smaller}}
@@ -12,7 +13,11 @@ int y __attribute__((aligned(1 << 28)));
 
 // PR3254
 short g0[3] __attribute__((aligned));
+#ifdef __iamcu
+short g0_chk[__alignof__(g0) == 4 ? 1 : -1];
+#else
 short g0_chk[__alignof__(g0) == 16 ? 1 : -1];
+#endif
 
 typedef char ueber_aligned_char __attribute__((aligned(8)));