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| author | Kaz Kylheku <kaz@kylheku.com> | 2025-06-17 21:09:16 -0700 |
|---|---|---|
| committer | Kaz Kylheku <kaz@kylheku.com> | 2025-06-17 21:09:16 -0700 |
| commit | 3dcd2869946e25041957e312fc3598a4f4639cf3 (patch) | |
| tree | 3b90d86928b455bbb2c77ddfdf7042608d3abadc /stdlib/compiler.tl | |
| parent | e10d748899c821a8ceba411fe24745023dae602b (diff) | |
| download | txr-3dcd2869946e25041957e312fc3598a4f4639cf3.tar.gz txr-3dcd2869946e25041957e312fc3598a4f4639cf3.tar.bz2 txr-3dcd2869946e25041957e312fc3598a4f4639cf3.zip | |
compiler: don't null tregs before closure.
* stdlib/compiler.tl (compiler eliminate-frame): New optional
no-tregs parameter. If true, it disables the generation of
code to null the tregs.
(compiler comp-lambda-impl): Pass t to no-regs parameter of
eliminate-frame to disable the nulling. It is not required
for a lambda which executes which fresh t-registers,
implicitly initialized to nil. The presence of these
instructions prevents the when-match pattern from matching,
which expects the instruction sequence to start with a
close instruction, so that the effect of eliminate-frame
is then lost. This is a latent bug exposed by the previous
commit. We would have seen this previously in a lambda
occurring inside a loop.
Diffstat (limited to 'stdlib/compiler.tl')
| -rw-r--r-- | stdlib/compiler.tl | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/stdlib/compiler.tl b/stdlib/compiler.tl index 002ef24d..fe4db13e 100644 --- a/stdlib/compiler.tl +++ b/stdlib/compiler.tl @@ -954,7 +954,7 @@ (uni tfrag.fvars [reduce-left uni cfrags nil .fvars]) (uni tfrag.ffuns [reduce-left uni cfrags nil .ffuns])))))))) -(defmeth compiler eliminate-frame (me code env) +(defmeth compiler eliminate-frame (me code env : no-tregs) (if (>= me.(unalloc-reg-count) (len env.vb)) (let ((trhash (hash)) (vbhash (hash)) @@ -987,7 +987,9 @@ (let ((vb [vbhash loc])) (set vb.loc treg))) me.(free-tregs tregs) - (append (mapcar (ret ^(mov ,@1 (t 0))) (nreverse tregs)) ncode))) + (if no-tregs + ncode + (append (mapcar (ret ^(mov ,@1 (t 0))) (nreverse tregs)) ncode)))) code)) (defmeth compiler comp-let (me oreg env form) @@ -1216,7 +1218,7 @@ me.(free-treg btreg) (when (and cspy (plusp frsize) (null cspy.cap-vars)) (when-match ((close @reg @frsize @nil . @irest) . @crest) - me.(eliminate-frame code nenv) + me.(eliminate-frame code nenv t) (set code ^((close ,reg 0 ,me.treg-cntr ,*irest) ,*crest)))) nenv.(unused-check form "parameter") |