| // 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 the register r12, and the condition codes, and uses r5 and r6 |
| // as temporaries by backing them up and restoring them afterwards. |
| // Does not modify any memory or the stack pointer. |
| |
| // movw r4, #256 // Number of bytes of stack, in units of 4 byte |
| // bl __chkstk |
| // sub.w sp, sp, r4 |
| |
| #define PAGE_SIZE 4096 |
| |
| .p2align 2 |
| DEFINE_COMPILERRT_FUNCTION(__chkstk) |
| lsl r4, r4, #2 |
| mov r12, sp |
| push {r5, r6} |
| mov r5, r4 |
| 1: |
| sub r12, r12, #PAGE_SIZE |
| subs r5, r5, #PAGE_SIZE |
| ldr r6, [r12] |
| bgt 1b |
| |
| pop {r5, r6} |
| bx lr |
| END_COMPILERRT_FUNCTION(__chkstk) |
