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| author | Quentin Carbonneaux <quentin@c9x.me> | 2022-11-24 11:08:33 +0100 |
|---|---|---|
| committer | Quentin Carbonneaux <quentin@c9x.me> | 2022-11-27 21:48:21 +0100 |
| commit | 9126afa2da0e1635d78429075cc44ca576f68169 (patch) | |
| tree | 0836f3da0fdfee9af24ca5dabb8244af61e5283e /amd64 | |
| parent | b5da3f3d64c857baf808220e202dc37c5c039eb8 (diff) | |
| download | roux-9126afa2da0e1635d78429075cc44ca576f68169.tar.gz | |
new hlt block terminator
It is handy to express when the end of a block cannot be reached. If a hlt terminator is executed, it traps the program. We don't go the llvm way and specify execution semantics as undefined behavior.
Diffstat (limited to 'amd64')
| -rw-r--r-- | amd64/emit.c | 3 | ||||
| -rw-r--r-- | amd64/isel.c | 4 |
2 files changed, 6 insertions, 1 deletions
diff --git a/amd64/emit.c b/amd64/emit.c index a034a66..9e5996b 100644 --- a/amd64/emit.c +++ b/amd64/emit.c @@ -582,6 +582,9 @@ amd64_emitfn(Fn *fn, FILE *f) emitins(*i, fn, f); lbl = 1; switch (b->jmp.type) { + case Jhlt: + fprintf(f, "\tud2\n"); + break; case Jret0: if (fn->dynalloc) fprintf(f, diff --git a/amd64/isel.c b/amd64/isel.c index 63c304a..6d62275 100644 --- a/amd64/isel.c +++ b/amd64/isel.c @@ -465,7 +465,9 @@ seljmp(Blk *b, Fn *fn) Ins *fi; Tmp *t; - if (b->jmp.type == Jret0 || b->jmp.type == Jjmp) + if (b->jmp.type == Jret0 + || b->jmp.type == Jjmp + || b->jmp.type == Jhlt) return; assert(b->jmp.type == Jjnz); r = b->jmp.arg; |