Refactor and correct the "is pure" and "can raise" (port upstream PR#10354 and PR#10387) #555
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xclerc
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Mar 2, 2022
gretay-js
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4.12.0-7
xclerc
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Mar 4, 2022
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mshinwell
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Apr 14, 2022
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@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
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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
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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
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May 20, 2022
fe8a98b flambda-backend: Save Mach as Cfg after Selection (oxcaml#624) 2b205d8 flambda-backend: Clean up algorithms (oxcaml#611) 524f0b4 flambda-backend: Initial refactoring of To_cmm (oxcaml#619) 0bf75de flambda-backend: Refactor and correct the "is pure" and "can raise" (port upstream PR#10354 and PR#10387) (oxcaml#555) d234bfd flambda-backend: Cpp mangling is now a configuration option (oxcaml#614) 20fc614 flambda-backend: Check that stack frames are not too large (#10085) (oxcaml#561) 5fc2e95 flambda-backend: Allow CSE of immutable loads across stores (port upstream PR#9562) (oxcaml#562) 2a650de flambda-backend: Backport commit fc95347 from trunk (oxcaml#584) 31651b8 flambda-backend: Improved ARM64 code generation (port upstream PR#9937) (oxcaml#556) f0b6d68 flambda-backend: Simplify processing and remove dead code (error paths) in asmlink (port upstream PR#9943) (oxcaml#557) 90c6746 flambda-backend: Improve code-generation for inlined comparisons (port upstream PR#10228) (oxcaml#563) git-subtree-dir: ocaml git-subtree-split: fe8a98b
mshinwell
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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
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Port ocaml/ocaml#10354 and ocaml/ocaml#10387