Handle ARM "ret void" and function alignment with proper padding.

src/IceCfg.cpp

Index: src/IceCfg.cpp
diff --git a/src/IceCfg.cpp b/src/IceCfg.cpp
index e0f48ab00d0e7e1c8fbbc91a517f071a4db71078..5b5c32b834adcd202452af1dc82162ef2294813a 100644
--- a/src/IceCfg.cpp
+++ b/src/IceCfg.cpp
@@ -464,9 +464,10 @@ void Cfg::emitTextHeader(const IceString &MangledName, GlobalContext *Ctx,
     Str << "\t.section\t.text." << MangledName << ",\"ax\",@progbits\n";
   if (!Asm->getInternal() || Ctx->getFlags().getDisableInternal()) {
     Str << "\t.globl\t" << MangledName << "\n";
-    Str << "\t.type\t" << MangledName << ",@function\n";
+    Str << "\t.type\t" << MangledName << ",%function\n";

[Jim Stichnoth, 2015/05/11 20:12:31]

% instead of @ is also OK for x86-32?

[jvoung (off chromium), 2015/05/11 22:11:50]

I think so.

Apparently there are 5 ways to state the type, because each target has different
comment characters:
https://sourceware.org/binutils/docs/as/Type.html#Type

It looks like "@" is a possible comment character for ARM. Couldn't find the
definitive source for that, but:

lib/Target/ARM/MCTargetDesc/ARMMCAsmInfo.cpp:  CommentString = "@";

http://stackoverflow.com/questions/15663280/gnu-assembler-comments/17168600#1...

Since this isn't "#" this should work for X86 too. Looks like Mips uses "#"
also.

   }
-  Str << "\t.p2align " << Asm->getBundleAlignLog2Bytes() << ",0x";
+  Str << "\t" << Asm->getNonExecPadDirective() << " "
+      << Asm->getBundleAlignLog2Bytes() << ",0x";
   for (uint8_t I : Asm->getNonExecBundlePadding())
     Str.write_hex(I);
   Str << "\n";