[llvm-commits] [dragonegg] r164837 - in /dragonegg/trunk: src/Convert.cpp test/validator/BitfieldRefAlignment.cpp

[Duncan Sands]

Author: baldrick
Date: Fri Sep 28 14:31:18 2012
New Revision: 164837

URL: http://llvm.org/viewvc/llvm-project?rev=164837&view=rev
Log:
Correct alignment computation when loading from a BIT_FIELD_REF.

Added:
    dragonegg/trunk/test/validator/BitfieldRefAlignment.cpp
Modified:
    dragonegg/trunk/src/Convert.cpp

Modified: dragonegg/trunk/src/Convert.cpp
URL: http://llvm.org/viewvc/llvm-project/dragonegg/trunk/src/Convert.cpp?rev=164837&r1=164836&r2=164837&view=diff
==============================================================================
--- dragonegg/trunk/src/Convert.cpp (original)
+++ dragonegg/trunk/src/Convert.cpp Fri Sep 28 14:31:18 2012
@@ -6063,6 +6063,8 @@
     // than this.  e.g. check out when compiling unwind-dw2-fde-darwin.c.
     Ptr.Ptr = Builder.CreateBitCast(Ptr.Ptr, ValTy->getPointerTo());
     Ptr.Ptr = Builder.CreateGEP(Ptr.Ptr, Builder.getInt32(UnitOffset));
+    unsigned OctetOffset = (UnitOffset * ValueSizeInBits) / 8;
+    Ptr.setAlignment(MinAlign(Ptr.getAlignment(), OctetOffset));
     BitStart -= UnitOffset*ValueSizeInBits;
   }
 

Added: dragonegg/trunk/test/validator/BitfieldRefAlignment.cpp
URL: http://llvm.org/viewvc/llvm-project/dragonegg/trunk/test/validator/BitfieldRefAlignment.cpp?rev=164837&view=auto
==============================================================================
--- dragonegg/trunk/test/validator/BitfieldRefAlignment.cpp (added)
+++ dragonegg/trunk/test/validator/BitfieldRefAlignment.cpp Fri Sep 28 14:31:18 2012
@@ -0,0 +1,15 @@
+// RUN: %dragonegg -S %s -o - | FileCheck %s
+// Overaligned load of field bf.
+
+struct S {
+  char s;
+  char bf : 3;                                     
+};
+
+void bar(S &);
+
+void foo(S &rhs) {
+  if (rhs.bf == 0)
+    bar(rhs);
+// CHECK: load i8* {{.*}}, align 1
+}