Revert r220153: "CodeGen: ConstStructBuilder must verify packed constraints after padding"

This commit caused two tests in LNT to regress. I'm able to reproduce on
any platform and will send reproduction steps to the original commit
log. This should restore the LNT bots that have been failing.

llvm-svn: 220169

2 files changed, 9 insertions, 21 deletions

diff --git a/clang/lib/CodeGen/CGExprConstant.cpp b/clang/lib/CodeGen/CGExprConstant.cpp
index dd87dd4657e..421e7deccc3 100644
--- a/clang/lib/CodeGen/CGExprConstant.cpp
+++ b/clang/lib/CodeGen/CGExprConstant.cpp
@@ -106,6 +106,15 @@ AppendBytes(CharUnits FieldOffsetInChars, llvm::Constant *InitCst) {
   CharUnits AlignedNextFieldOffsetInChars =
     NextFieldOffsetInChars.RoundUpToAlignment(FieldAlignment);
 
+  if (AlignedNextFieldOffsetInChars > FieldOffsetInChars) {
+    assert(!Packed && "Alignment is wrong even with a packed struct!");
+
+    // Convert the struct to a packed struct.
+    ConvertStructToPacked();
+
+    AlignedNextFieldOffsetInChars = NextFieldOffsetInChars;
+  }
+
   if (AlignedNextFieldOffsetInChars < FieldOffsetInChars) {
     // We need to append padding.
     AppendPadding(FieldOffsetInChars - NextFieldOffsetInChars);
@@ -113,16 +122,6 @@ AppendBytes(CharUnits FieldOffsetInChars, llvm::Constant *InitCst) {
     assert(NextFieldOffsetInChars == FieldOffsetInChars &&
            "Did not add enough padding!");
 
-    AlignedNextFieldOffsetInChars =
-      NextFieldOffsetInChars.RoundUpToAlignment(FieldAlignment);
-  }
-
-  if (AlignedNextFieldOffsetInChars > FieldOffsetInChars) {
-    assert(!Packed && "Alignment is wrong even with a packed struct!");
-
-    // Convert the struct to a packed struct.
-    ConvertStructToPacked();
-
     AlignedNextFieldOffsetInChars = NextFieldOffsetInChars;
   }
 
diff --git a/clang/test/CodeGen/const-init.c b/clang/test/CodeGen/const-init.c
index ccc6604c456..7d7ccae370d 100644
--- a/clang/test/CodeGen/const-init.c
+++ b/clang/test/CodeGen/const-init.c
@@ -159,14 +159,3 @@ void g29() {
   static int b[1] = { "asdf" }; // expected-warning {{incompatible pointer to integer conversion initializing 'int' with an expression of type 'char [5]'}}
   static int c[1] = { L"a" };
 }
-
-// PR21300
-void g30() {
-#pragma pack(1)
-  static struct {
-    int : 1;
-    int x;
-  } a = {};
-  // CHECK: @g30.a = internal global %struct.anon.1 <{ i8 undef, i32 0 }>, align 1
-#pragma pack()
-}