[X86][mingw] Modify the alignment of __m128/__m256/__m512 vector type…

… for mingw

This is a follow up patch after D78564 and D108887.

Martin helped to confirm the alignment in GCC mingw is the same as the
size of vector. https://reviews.llvm.org/D108887#inline-1040893

Reviewed By: mstorsjo

Differential Revision: https://reviews.llvm.org/D109265

clang/lib/CodeGen/TargetInfo.cpp

@@ -1170,7 +1170,8 @@ class X86_32ABIInfo : public SwiftABIInfo {
       IsRetSmallStructInRegABI(RetSmallStructInRegABI),
       IsWin32StructABI(Win32StructABI), IsSoftFloatABI(SoftFloatABI),
       IsMCUABI(CGT.getTarget().getTriple().isOSIAMCU()),
-      IsLinuxABI(CGT.getTarget().getTriple().isOSLinux()),
+      IsLinuxABI(CGT.getTarget().getTriple().isOSLinux() ||
+                 CGT.getTarget().getTriple().isOSCygMing()),
       DefaultNumRegisterParameters(NumRegisterParameters) {}
 
   bool shouldPassIndirectlyForSwift(ArrayRef<llvm::Type*> scalars,

clang/test/CodeGen/x86_32-align-linux.c

@@ -1,6 +1,9 @@
 // RUN: %clang_cc1 -w -fblocks -ffreestanding -triple i386-pc-linux-gnu -emit-llvm -o - %s | FileCheck %s
 // RUN: %clang_cc1 -w -fblocks -ffreestanding -triple i386-pc-linux-gnu -target-feature +avx -emit-llvm -o - %s | FileCheck %s
 // RUN: %clang_cc1 -w -fblocks -ffreestanding -triple i386-pc-linux-gnu -target-feature +avx512f -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -w -fblocks -ffreestanding -triple i386-pc-linux-mingw -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -w -fblocks -ffreestanding -triple i386-pc-linux-mingw -target-feature +avx -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -w -fblocks -ffreestanding -triple i386-pc-linux-mingw -target-feature +avx512f -emit-llvm -o - %s | FileCheck %s
 
 #include <immintrin.h>