X86: Add alloca probing to dynamic alloca on Windows. Fixes PR8424.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116984 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 8 insertions, 8 deletions

diff --git a/lib/Target/X86/X86InstrCompiler.td b/lib/Target/X86/X86InstrCompiler.td
index dda8e4f..64a7354 100644
--- a/lib/Target/X86/X86InstrCompiler.td
+++ b/lib/Target/X86/X86InstrCompiler.td
@@ -94,18 +94,18 @@ def VAARG_64 : I<0, Pseudo,
                     (X86vaarg64 addr:$ap, imm:$size, imm:$mode, imm:$align)),
                   (implicit EFLAGS)]>;
 
-// Dynamic stack allocation yields _alloca call for Cygwin/Mingw targets.  Calls
-// to _alloca is needed to probe the stack when allocating more than 4k bytes in
-// one go. Touching the stack at 4K increments is necessary to ensure that the
-// guard pages used by the OS virtual memory manager are allocated in correct
-// sequence.
+// Dynamic stack allocation yields a _chkstk or _alloca call for all Windows
+// targets.  These calls are needed to probe the stack when allocating more than
+// 4k bytes in one go. Touching the stack at 4K increments is necessary to
+// ensure that the guard pages used by the OS virtual memory manager are
+// allocated in correct sequence.
 // The main point of having separate instruction are extra unmodelled effects
 // (compared to ordinary calls) like stack pointer change.
 
 let Defs = [EAX, ESP, EFLAGS], Uses = [ESP] in
-  def MINGW_ALLOCA : I<0, Pseudo, (outs), (ins),
-                       "# dynamic stack allocation",
-                       [(X86MingwAlloca)]>;
+  def WIN_ALLOCA : I<0, Pseudo, (outs), (ins),
+                     "# dynamic stack allocation",
+                     [(X86WinAlloca)]>;
 }