Align function starts to target-specific bundle alignment.

src/IceTargetLowering.h

Index: src/IceTargetLowering.h
diff --git a/src/IceTargetLowering.h b/src/IceTargetLowering.h
index 6bf142487eb520aaee58570acef2341a84fbf0ed..54cf2f23e024f9f481b80dda6c1a3a3d4e70698b 100644
--- a/src/IceTargetLowering.h
+++ b/src/IceTargetLowering.h
@@ -137,6 +137,8 @@ public:
   virtual bool hasFramePointer() const { return false; }
   virtual SizeT getFrameOrStackReg() const = 0;
   virtual size_t typeWidthInBytesOnStack(Type Ty) const = 0;
+  virtual SizeT getBundleAlignLog2Bytes() const = 0;
+  virtual IceString getNonExecBundlePadding() const = 0;

[jvoung (off chromium), 2014/08/28 21:02:22]

IceString, or const char *?

[Jim Stichnoth, 2014/08/28 21:22:22]

I was actually wondering if it should be uint8_t.  That may be more painful to
render in textual assembly, but much easier for an integrated assembler. 
Regardless, the other issue is that we're constraining padding to single-byte
encoded instructions, but that's probably OK.

[jvoung (off chromium), 2014/08/28 22:38:13]

True, we'll need the raw bytes.  I made this an ArrayRef<uint8_t>, and used
raw_ostream's write_hex().

   bool hasComputedFrame() const { return HasComputedFrame; }
   bool shouldDoNopInsertion() const;
   int32_t getStackAdjustment() const { return StackAdjustment; }