[PATCH] Add a "probe-stack" attribute

[John Kåre Alsaker]

This is originally 4 commits: https://github.com/Zoxc/llvm/compare/llvm-mirror:master...stprobe

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Comment at: lib/Target/X86/X86FrameLowering.cpp:752
@@ +751,3 @@
+      if (isRegAccAlive) {
+          // Restore RegAcc
+          auto MIB = BuildMI(MF, DL,
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Reid Kleckner wrote:
> Should be 2 space indentation
The original code has 4 space indentation here. Don't blame me.

http://reviews.llvm.org/D4717