[PATCH] Preprocessor: improve ACLE 6.4 support

[Tim Northover]

Hi Saleem,

I think this looks fine, but while you're in the area it looks like there's a bug in how __ARM_ARCH_PROFILE is defined:

================
Comment at: test/Preprocessor/arm-acle-6.4.c:7
@@ +6,3 @@
+// CHECK-CORTEX-M0: __ARM_ARCH_ISA_THUMB 1
+// CHECK-CORTEX-M0: __ARM_ARCH_PROFILE M
+
----------------
Just noticed this one, and I think it might be a misinterpretation of the ACLE. I would expect this to be the character value 'M' rather than some isolated token.

A quick GCC test suggests this is how they do it ("#define __ARM_ARCH_PROFILE 65" for Cortex-A15, which is also dodgy in C++ mode, but less so).

http://reviews.llvm.org/D4146