[llvm-commits] [WinABI patch] Make sure to call __chkstk when appropriate

Anton Korobeynikov asl at math.spbu.ru
Wed Aug 18 02:43:57 PDT 2010

Hello, Cameron

> Windows ABI requires the function prologue to call __chkstk if there is >= 4096 bytes allocated on the stack.
The patch is invalid due to many reasons:
 - It does the stuff in wrong place
 - It clobbers eax which can be incoming arg reg in case of inreg
params / fast CC
 - __chkstk is same as __alloca call in mingw case, which is already implemented

Also, I don't recall offhand, but iirc this call had some special CC,
it clobbers quite alot of regs, etc.

With best regards, Anton Korobeynikov
Faculty of Mathematics and Mechanics, Saint Petersburg State University

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