[PATCH] [AArch64] Enable post-RA MI scheduler

[Chad Rosier]

Is anyone opposed to this being pushed. Jiangning confirmed the performance findings on A57.  Internally, we saw good numbers on an A53 devices.  No serious compile time regressions were reported.  I'd like to get this in before our weekend performance run, so please let me know.

 Chad

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Comment at: test/CodeGen/AArch64/arm64-postra-mi-sched.ll:1
@@ +1,2 @@
+; RUN: llc < %s -O3 -march=arm64 -mcpu=cortex-a53 | FileCheck %s
+; With cortex-a53, each of fmul and fcvt have latency of 6 cycles.  After the
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I'll update the -march to use aarch64 before pushing.

http://reviews.llvm.org/D5278