Refactor and correct the "is pure" and "can raise" (port upstream PR#10354 and PR#10387) #555
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
xclerc
reviewed
Mar 2, 2022
gretay-js
added
4.12.0-7
xclerc
approved these changes
Mar 4, 2022
8 tasks
mshinwell
approved these changes
Apr 14, 2022
|
@gretay-js Please could you resolve the conflicts, then this should be ready to merge. |
These two predicates test properties of Mach operations. For the standard operations, the results are independent of the target platform. For the platform-specific operations, results vary. The "is pure" predicate was implemented in a platform-specific file, $ARCH/proc.ml. The treatment of standard operations was duplicated. The "can raise" predicate was implemented in a platform-independent file, mach.ml. All specific operations were assumed not to raise, which is incorrect for ARM and ARM64 and their "shiftcheckbound" specific operation. (See #10339.) This commit refactors the two predicates as follows: - `Arch.operation_is_pure` and `Arch.operation_can_raise` predicates are added to each platform description file. They deal with specific operations only. - `Mach.operation_is_pure` was added and `Mach.operation_can_raise` was fixed to implement the test for standard operations and delegate to the Arch functions for specific operations.
The ARM and ARM64 architectures have `Ishiftcheckbound` specific instructions that can raise an Invalid_argument exception. This exception can, in turn, be handled in the same function (see PR#10339 for an example). However, these specific instructions were not taken into account during insertion of spill code in asmcomp/spill.ml. The consequence is a variable that is reloaded from stack in the exception handler, yet has not been spilled to stack before. This commit fixes the issue by using the recently-fixed `Mach.operation_can_raise` predicate to handle operations during spill code insertion, instead of an ad-hoc pattern-matching. Fixes: PR#10339
… analysis (#10387) This is a follow-up to 15e6354 and #10354. Use the `Mach.operation_can_raise` predicate instead of an ad-hoc pattern matching to spot operations where the variables live at entry to the enclosing exception handler must also be live. The ad-hoc pattern matching was missing the `Ishiftcheckbound` specific operations of ARM and ARM64.
lpw25
added a commit
that referenced
this pull request
May 19, 2022
fe8a98b flambda-backend: Save Mach as Cfg after Selection (#624) 2b205d8 flambda-backend: Clean up algorithms (#611) 524f0b4 flambda-backend: Initial refactoring of To_cmm (#619) 0bf75de flambda-backend: Refactor and correct the "is pure" and "can raise" (port upstream PR#10354 and PR#10387) (#555) d234bfd flambda-backend: Cpp mangling is now a configuration option (#614) 20fc614 flambda-backend: Check that stack frames are not too large (#10085) (#561) 5fc2e95 flambda-backend: Allow CSE of immutable loads across stores (port upstream PR#9562) (#562) 2a650de flambda-backend: Backport commit fc95347 from trunk (#584) 31651b8 flambda-backend: Improved ARM64 code generation (port upstream PR#9937) (#556) f0b6d68 flambda-backend: Simplify processing and remove dead code (error paths) in asmlink (port upstream PR#9943) (#557) 90c6746 flambda-backend: Improve code-generation for inlined comparisons (port upstream PR#10228) (#563) git-subtree-dir: ocaml git-subtree-split: fe8a98b
mshinwell
pushed a commit
that referenced
this pull request
May 20, 2022
…10354 and PR#10387) (#555) * Refactor Proc.op_is_pure and fix Mach.operation_can_raise These two predicates test properties of Mach operations. For the standard operations, the results are independent of the target platform. For the platform-specific operations, results vary. The "is pure" predicate was implemented in a platform-specific file, $ARCH/proc.ml. The treatment of standard operations was duplicated. The "can raise" predicate was implemented in a platform-independent file, mach.ml. All specific operations were assumed not to raise, which is incorrect for ARM and ARM64 and their "shiftcheckbound" specific operation. (See #10339.) This commit refactors the two predicates as follows: - `Arch.operation_is_pure` and `Arch.operation_can_raise` predicates are added to each platform description file. They deal with specific operations only. - `Mach.operation_is_pure` was added and `Mach.operation_can_raise` was fixed to implement the test for standard operations and delegate to the Arch functions for specific operations. * Fix handling of exception-raising specific operations during spilling The ARM and ARM64 architectures have `Ishiftcheckbound` specific instructions that can raise an Invalid_argument exception. This exception can, in turn, be handled in the same function (see PR#10339 for an example). However, these specific instructions were not taken into account during insertion of spill code in asmcomp/spill.ml. The consequence is a variable that is reloaded from stack in the exception handler, yet has not been spilled to stack before. This commit fixes the issue by using the recently-fixed `Mach.operation_can_raise` predicate to handle operations during spill code insertion, instead of an ad-hoc pattern-matching. Fixes: PR#10339 * Fix handling of exception-raising specific operations during liveness analysis (#10387) This is a follow-up to 15e6354 and #10354. Use the `Mach.operation_can_raise` predicate instead of an ad-hoc pattern matching to spot operations where the variables live at entry to the enclosing exception handler must also be live. The ad-hoc pattern matching was missing the `Ishiftcheckbound` specific operations of ARM and ARM64. * Handle flambda-backend operations * Update cfg * Iprobe_is_enabled is pure * Exhaustive match * Fix after rebase * Fix arm64 after rebase and cleanup Co-authored-by: Xavier Leroy <xavier.leroy@college-de-france.fr> Co-authored-by: Xavier Leroy <xavierleroy@users.noreply.github.com>
lpw25
added a commit
to lpw25/flambda-backend
that referenced
this pull request
May 20, 2022
fe8a98b flambda-backend: Save Mach as Cfg after Selection (ocaml-flambda#624) 2b205d8 flambda-backend: Clean up algorithms (ocaml-flambda#611) 524f0b4 flambda-backend: Initial refactoring of To_cmm (ocaml-flambda#619) 0bf75de flambda-backend: Refactor and correct the "is pure" and "can raise" (port upstream PR#10354 and PR#10387) (ocaml-flambda#555) d234bfd flambda-backend: Cpp mangling is now a configuration option (ocaml-flambda#614) 20fc614 flambda-backend: Check that stack frames are not too large (#10085) (ocaml-flambda#561) 5fc2e95 flambda-backend: Allow CSE of immutable loads across stores (port upstream PR#9562) (ocaml-flambda#562) 2a650de flambda-backend: Backport commit fc95347 from trunk (ocaml-flambda#584) 31651b8 flambda-backend: Improved ARM64 code generation (port upstream PR#9937) (ocaml-flambda#556) f0b6d68 flambda-backend: Simplify processing and remove dead code (error paths) in asmlink (port upstream PR#9943) (ocaml-flambda#557) 90c6746 flambda-backend: Improve code-generation for inlined comparisons (port upstream PR#10228) (ocaml-flambda#563) git-subtree-dir: ocaml git-subtree-split: fe8a98b
mshinwell
added a commit
that referenced
this pull request
May 24, 2022
454150b flambda-backend: Speed up testsuite (#658) 8362f9e flambda-backend: Speed up builds (#585) a527cab flambda-backend: Update backends for changes from ocaml-jst ce88833 Merge flambda-backend changes b7506bb Revert "Cherry-pick of ocaml/ocaml 1eeb0e7fe595f5f9e1ea1edbdf785ff3b49feeeb (#12)" 183f688 Add config option to enable/disable stack allocation (#22) ee7c849 If both the type and mode of an ident are wrong, complain about the type. (#19) 44bade0 Allow submoding during module inclusion checks (#21) de3bec9 Add subtyping between arrows of related modes (#20) fe8a98b flambda-backend: Save Mach as Cfg after Selection (#624) 2b205d8 flambda-backend: Clean up algorithms (#611) 93d8615 Enable the local keywords even when the local extension is off (#18) 524f0b4 flambda-backend: Initial refactoring of To_cmm (#619) 81dd85e Documentation for local allocations b05519f Fix a GC bug in local stack scanning (#17) 9f879de Fix __FUNCTION__ (#15) 0bf75de flambda-backend: Refactor and correct the "is pure" and "can raise" (port upstream PR#10354 and PR#10387) (#555) d234bfd flambda-backend: Cpp mangling is now a configuration option (#614) 20fc614 flambda-backend: Check that stack frames are not too large (#10085) (#561) 5fc2e95 flambda-backend: Allow CSE of immutable loads across stores (port upstream PR#9562) (#562) 2a650de flambda-backend: Backport commit fc95347 from trunk (#584) a78975e Optimise "include struct ... end" in more cases (ocaml/ocaml#11134) b819c66 Cherry-pick of ocaml/ocaml 1eeb0e7fe595f5f9e1ea1edbdf785ff3b49feeeb (#12) bb363d4 Optimise the allocation of optional arguments (#11) 31651b8 flambda-backend: Improved ARM64 code generation (port upstream PR#9937) (#556) f0b6d68 flambda-backend: Simplify processing and remove dead code (error paths) in asmlink (port upstream PR#9943) (#557) 90c6746 flambda-backend: Improve code-generation for inlined comparisons (port upstream PR#10228) (#563) git-subtree-dir: ocaml git-subtree-split: 454150b
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Port ocaml/ocaml#10354 and ocaml/ocaml#10387