[VE] Correct stack alignment

[kaz7]

Summary

Change stack alignment from 64 bits to 128 bits to follow ABI correctly.
And add a regression test for datalayout.

clang/lib/Basic/Targets/VE.h

VETargetInfo(const llvm::Triple &Triple, const TargetOptions &)
     IntMaxType = SignedLong;
     Int64Type = SignedLong;
     RegParmMax = 8;
     MaxAtomicPromoteWidth = MaxAtomicInlineWidth = 64;
 
     WCharType = UnsignedInt;
     WIntType = UnsignedInt;
     UseZeroLengthBitfieldAlignment = true;
-    resetDataLayout("e-m:e-i64:64-n32:64-S64");
+    resetDataLayout("e-m:e-i64:64-n32:64-S128");
   }
 
   void getTargetDefines(const LangOptions &Opts,
                         MacroBuilder &Builder) const override;
 
   bool hasSjLjLowering() const override {
     // TODO
     return false;

clang/test/CodeGen/target-data.c

 
 // RUN: %clang_cc1 -triple bpfel -o - -emit-llvm %s | \
 // RUN: FileCheck %s -check-prefix=BPFEL
 // BPFEL: target datalayout = "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128"
 
 // RUN: %clang_cc1 -triple bpfeb -o - -emit-llvm %s | \
 // RUN: FileCheck %s -check-prefix=BPFEB
 // BPFEB: target datalayout = "E-m:e-p:64:64-i64:64-i128:128-n32:64-S128"
+
+// RUN: %clang_cc1 -triple ve -o - -emit-llvm %s | \
+// RUN: FileCheck %s -check-prefix=VE
+// VE: target datalayout = "e-m:e-i64:64-n32:64-S128"

llvm/lib/Target/VE/VETargetMachine.cpp

static std::string computeDataLayout(const Triple &T) {
   Ret += "-m:e";
 
   // Alignments for 64 bit integers.
   Ret += "-i64:64";
 
   // VE supports 32 bit and 64 bits integer on registers
   Ret += "-n32:64";
 
-  // Stack alignment is 64 bits
-  Ret += "-S64";
+  // Stack alignment is 128 bits
+  Ret += "-S128";
 
   return Ret;
 }
 
 static Reloc::Model getEffectiveRelocModel(Optional<Reloc::Model> RM) {
   if (!RM.hasValue())
     return Reloc::Static;
   return *RM;