1; RUN: llc < %s -mtriple=i686-pc-win32 | FileCheck %s -check-prefix=WIN_X32 2; RUN: llc < %s -mtriple=x86_64-pc-win32 | FileCheck %s -check-prefix=WIN_X64 3; RUN: llc < %s -mtriple=i686-pc-mingw32 | FileCheck %s -check-prefix=MINGW_X32 4; RUN: llc < %s -mtriple=x86_64-pc-mingw32 | FileCheck %s -check-prefix=MINGW_X64 5; RUN: llc < %s -mtriple=i386-pc-linux | FileCheck %s -check-prefix=LINUX 6; RUN: llc < %s -mtriple=x86_64-pc-win32-macho | FileCheck %s -check-prefix=LINUX 7 8; Windows and mingw require a prologue helper routine if more than 4096 bytes area 9; allocated on the stack. Windows uses __chkstk and mingw uses __alloca. __alloca 10; and the 32-bit version of __chkstk will probe the stack and adjust the stack pointer. 11; The 64-bit version of __chkstk is only responsible for probing the stack. The 64-bit 12; prologue is responsible for adjusting the stack pointer. 13 14; Stack allocation >= 4096 bytes will require call to __chkstk in the Windows ABI. 15define i32 @main4k() nounwind { 16entry: 17; WIN_X32: calll __chkstk 18; WIN_X64: callq __chkstk 19; MINGW_X32: calll __alloca 20; MINGW_X64: callq ___chkstk 21; LINUX-NOT: call __chkstk 22 %array4096 = alloca [4096 x i8], align 16 ; <[4096 x i8]*> [#uses=0] 23 ret i32 0 24} 25 26; Make sure we don't call __chkstk or __alloca when we have less than a 4096 stack 27; allocation. 28define i32 @main128() nounwind { 29entry: 30; WIN_X32: # BB#0: 31; WIN_X32-NOT: calll __chkstk 32; WIN_X32: ret 33 34; WIN_X64: # BB#0: 35; WIN_X64-NOT: callq __chkstk 36; WIN_X64: ret 37 38; MINGW_X64: # BB#0: 39; MINGW_X64-NOT: callq _alloca 40; MINGW_X64: ret 41 42; LINUX: # BB#0: 43; LINUX-NOT: call __chkstk 44; LINUX: ret 45 %array128 = alloca [128 x i8], align 16 ; <[128 x i8]*> [#uses=0] 46 ret i32 0 47} 48