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| author | Björn Gustavsson <[email protected]> | 2016-03-31 06:55:31 +0200 |
|---|---|---|
| committer | Björn Gustavsson <[email protected]> | 2016-03-31 10:03:38 +0200 |
| commit | 7d06e5ecd47ef071eb8c4e58ead70e79fa4b02b2 (patch) | |
| tree | 54dffc98449cde17cdd12b73101508afae16b40b /erts/emulator/beam | |
| parent | d166fec5d5c901a93e21a1ea7b3165b6fe68d320 (diff) | |
| download | otp-7d06e5ecd47ef071eb8c4e58ead70e79fa4b02b2.tar.gz otp-7d06e5ecd47ef071eb8c4e58ead70e79fa4b02b2.tar.bz2 otp-7d06e5ecd47ef071eb8c4e58ead70e79fa4b02b2.zip | |
Fix unsafe transformation of apply/3 with fixed arguments
62473daf introduced an unsafe optimization in the loader.
See the comments in the test case for an explanation of
the problem.
Diffstat (limited to 'erts/emulator/beam')
| -rw-r--r-- | erts/emulator/beam/beam_load.c | 7 | ||||
| -rw-r--r-- | erts/emulator/beam/ops.tab | 2 |
2 files changed, 8 insertions, 1 deletions
diff --git a/erts/emulator/beam/beam_load.c b/erts/emulator/beam/beam_load.c index d3d278fb81..16cbdbffea 100644 --- a/erts/emulator/beam/beam_load.c +++ b/erts/emulator/beam/beam_load.c @@ -2735,6 +2735,13 @@ same_label(LoaderState* stp, GenOpArg Target, GenOpArg Label) } static int +is_killed_apply(LoaderState* stp, GenOpArg Reg, GenOpArg Live) +{ + return Reg.type == TAG_x && Live.type == TAG_u && + Live.val+2 <= Reg.val; +} + +static int is_killed(LoaderState* stp, GenOpArg Reg, GenOpArg Live) { return Reg.type == TAG_x && Live.type == TAG_u && diff --git a/erts/emulator/beam/ops.tab b/erts/emulator/beam/ops.tab index 9e53b4bfcc..772460c177 100644 --- a/erts/emulator/beam/ops.tab +++ b/erts/emulator/beam/ops.tab @@ -303,7 +303,7 @@ move_window5 x x x x x y # Swap registers. move R1=x Tmp=x | move R2=xy R1 | move Tmp R2 => swap_temp R1 R2 Tmp -swap_temp R1 R2 Tmp | line Loc | apply Live | is_killed(Tmp, Live) => \ +swap_temp R1 R2 Tmp | line Loc | apply Live | is_killed_apply(Tmp, Live) => \ swap R1 R2 | line Loc | apply Live swap_temp R1 R2 Tmp | line Loc | call Live Addr | is_killed(Tmp, Live) => \ |