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| author | Michael Forney <mforney@mforney.org> | 2020-04-19 16:31:55 -0700 |
|---|---|---|
| committer | Quentin Carbonneaux <quentin@c9x.me> | 2020-08-06 10:09:28 +0200 |
| commit | 84f1e2950b3ab41523f25d205c99e9d8afd7ebba (patch) | |
| tree | 1f5fa855fc58f26dd7ba75ea36dc3d157a4db606 /arm64/emit.c | |
| parent | 706d6beca6218caf76f0107d15e79a8f3af1646a (diff) | |
| download | roux-84f1e2950b3ab41523f25d205c99e9d8afd7ebba.tar.gz | |
arm64: Make sure SP stays aligned by 16
According to the ARMv8 overview document However if SP is used as the base register then the value of the stack pointer prior to adding any offset must be quadword (16 byte) aligned, or else a stack alignment exception will be generated. This manifests as a bus error on my system. To resolve this, just save registers two at a time with stp.
Diffstat (limited to 'arm64/emit.c')
| -rw-r--r-- | arm64/emit.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arm64/emit.c b/arm64/emit.c index 59e1aae..892d027 100644 --- a/arm64/emit.c +++ b/arm64/emit.c @@ -378,8 +378,8 @@ arm64_emitfn(Fn *fn, FILE *out) if (e->fn->vararg) { for (n=7; n>=0; n--) fprintf(e->f, "\tstr\tq%d, [sp, -16]!\n", n); - for (n=7; n>=0; n--) - fprintf(e->f, "\tstr\tx%d, [sp, -8]!\n", n); + for (n=7; n>=0; n-=2) + fprintf(e->f, "\tstp\tx%d, x%d, [sp, -16]!\n", n-1, n); } if (e->frame + 16 <= 512) |