[X86] Elide references to _chkstk for dynamic allocas
The _chkstk function is called by the compiler to probe the stack in an
order consistent with Windows' expectations. However, it is possible to
elide the call to _chkstk and manually adjust the stack pointer if we
can prove that the allocation is fixed size and smaller than the probe
size.
This shrinks chrome.dll, chrome_child.dll and chrome.exe by a
cummulative ~133 KB.
Differential Revision: http://reviews.llvm.org/D17679
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@262370 91177308-0d34-0410-b5e6-96231b3b80d8
8 files changed