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-rw-r--r--contrib/llvm-project/compiler-rt/lib/builtins/aarch64/chkstk.S35
1 files changed, 35 insertions, 0 deletions
diff --git a/contrib/llvm-project/compiler-rt/lib/builtins/aarch64/chkstk.S b/contrib/llvm-project/compiler-rt/lib/builtins/aarch64/chkstk.S
new file mode 100644
index 000000000000..01f90366f030
--- /dev/null
+++ b/contrib/llvm-project/compiler-rt/lib/builtins/aarch64/chkstk.S
@@ -0,0 +1,35 @@
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#include "../assembly.h"
+
+// __chkstk routine
+// This routine is windows specific.
+// http://msdn.microsoft.com/en-us/library/ms648426.aspx
+
+// This clobbers registers x16 and x17.
+// Does not modify any memory or the stack pointer.
+
+// mov x15, #256 // Number of bytes of stack, in units of 16 byte
+// bl __chkstk
+// sub sp, sp, x15, lsl #4
+
+#ifdef __aarch64__
+
+#define PAGE_SIZE 4096
+
+ .p2align 2
+DEFINE_COMPILERRT_FUNCTION(__chkstk)
+ lsl x16, x15, #4
+ mov x17, sp
+1:
+ sub x17, x17, #PAGE_SIZE
+ subs x16, x16, #PAGE_SIZE
+ ldr xzr, [x17]
+ b.gt 1b
+
+ ret
+END_COMPILERRT_FUNCTION(__chkstk)
+
+#endif // __aarch64__