Fix the alignment on scalar parameter variables so that it matches what the AST thinks it should be. Per report on cfe-dev.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@143645 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/CGDecl.cpp

@@ -1442,7 +1442,10 @@ void CodeGenFunction::EmitParmDecl(const VarDecl &D, llvm::Value *Arg,
     DeclPtr = Arg;
   } else {
     // Otherwise, create a temporary to hold the value.
-    DeclPtr = CreateMemTemp(Ty, D.getName() + ".addr");
+    llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertTypeForMem(Ty),
+                                               D.getName() + ".addr");
+    Alloc->setAlignment(getContext().getDeclAlign(&D).getQuantity());
+    DeclPtr = Alloc;
 
     bool doStore = true;
 

test/CodeGen/align-param.c

@@ -0,0 +1,9 @@
+// RUN: %clang_cc1 -emit-llvm -triple i386-apple-macosx10.7.2 < %s | FileCheck %s
+
+// The preferred alignment for a long long on x86-32 is 8; make sure the
+// alloca for x uses that alignment.
+int test (long long x) {
+  return (int)x;
+}
+// CHECK: define i32 @test
+// CHECK: alloca i64, align 8