forked from OSchip/llvm-project
18 Commits
Author | SHA1 | Message | Date |
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Nirav Dave | 54e22f33d9 |
In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
Recommiting with compiler time improvements Recommitting after fixup of 32-bit aliasing sign offset bug in DAGCombiner. * Simplify Consecutive Merge Store Candidate Search Now that address aliasing is much less conservative, push through simplified store merging search and chain alias analysis which only checks for parallel stores through the chain subgraph. This is cleaner as the separation of non-interfering loads/stores from the store-merging logic. When merging stores search up the chain through a single load, and finds all possible stores by looking down from through a load and a TokenFactor to all stores visited. This improves the quality of the output SelectionDAG and the output Codegen (save perhaps for some ARM cases where we correctly constructs wider loads, but then promotes them to float operations which appear but requires more expensive constant generation). Some minor peephole optimizations to deal with improved SubDAG shapes (listed below) Additional Minor Changes: 1. Finishes removing unused AliasLoad code 2. Unifies the chain aggregation in the merged stores across code paths 3. Re-add the Store node to the worklist after calling SimplifyDemandedBits. 4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is arbitrary, but seems sufficient to not cause regressions in tests. 5. Remove Chain dependencies of Memory operations on CopyfromReg nodes as these are captured by data dependence 6. Forward loads-store values through tokenfactors containing {CopyToReg,CopyFromReg} Values. 7. Peephole to convert buildvector of extract_vector_elt to extract_subvector if possible (see CodeGen/AArch64/store-merge.ll) 8. Store merging for the ARM target is restricted to 32-bit as some in some contexts invalid 64-bit operations are being generated. This can be removed once appropriate checks are added. This finishes the change Matt Arsenault started in r246307 and jyknight's original patch. Many tests required some changes as memory operations are now reorderable, improving load-store forwarding. One test in particular is worth noting: CodeGen/PowerPC/ppc64-align-long-double.ll - Improved load-store forwarding converts a load-store pair into a parallel store and a memory-realized bitcast of the same value. However, because we lose the sharing of the explicit and implicit store values we must create another local store. A similar transformation happens before SelectionDAG as well. Reviewers: arsenm, hfinkel, tstellarAMD, jyknight, nhaehnle llvm-svn: 297695 |
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Chandler Carruth | ce52b80744 |
[SDAG] Revert r296476 (and r296486, r296668, r296690).
This patch causes compile times for some patterns to explode. I have a (large, unreduced) test case that slows down by more than 20x and several test cases slow down by 2x. I'm sending some of the test cases directly to Nirav and following up with more details in the review log, but this should unblock anyone else hitting this. llvm-svn: 296862 |
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Nirav Dave | f830dec3f2 |
In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
Recommiting after fixup of 32-bit aliasing sign offset bug in DAGCombiner. * Simplify Consecutive Merge Store Candidate Search Now that address aliasing is much less conservative, push through simplified store merging search and chain alias analysis which only checks for parallel stores through the chain subgraph. This is cleaner as the separation of non-interfering loads/stores from the store-merging logic. When merging stores search up the chain through a single load, and finds all possible stores by looking down from through a load and a TokenFactor to all stores visited. This improves the quality of the output SelectionDAG and the output Codegen (save perhaps for some ARM cases where we correctly constructs wider loads, but then promotes them to float operations which appear but requires more expensive constant generation). Some minor peephole optimizations to deal with improved SubDAG shapes (listed below) Additional Minor Changes: 1. Finishes removing unused AliasLoad code 2. Unifies the chain aggregation in the merged stores across code paths 3. Re-add the Store node to the worklist after calling SimplifyDemandedBits. 4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is arbitrary, but seems sufficient to not cause regressions in tests. 5. Remove Chain dependencies of Memory operations on CopyfromReg nodes as these are captured by data dependence 6. Forward loads-store values through tokenfactors containing {CopyToReg,CopyFromReg} Values. 7. Peephole to convert buildvector of extract_vector_elt to extract_subvector if possible (see CodeGen/AArch64/store-merge.ll) 8. Store merging for the ARM target is restricted to 32-bit as some in some contexts invalid 64-bit operations are being generated. This can be removed once appropriate checks are added. This finishes the change Matt Arsenault started in r246307 and jyknight's original patch. Many tests required some changes as memory operations are now reorderable, improving load-store forwarding. One test in particular is worth noting: CodeGen/PowerPC/ppc64-align-long-double.ll - Improved load-store forwarding converts a load-store pair into a parallel store and a memory-realized bitcast of the same value. However, because we lose the sharing of the explicit and implicit store values we must create another local store. A similar transformation happens before SelectionDAG as well. Reviewers: arsenm, hfinkel, tstellarAMD, jyknight, nhaehnle llvm-svn: 296476 |
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Nirav Dave | 73cd0194cf |
Revert "In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled."
This reverts commit r296252 until 256-bit operations are more efficiently generated in X86. llvm-svn: 296279 |
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Nirav Dave | beabf456df |
In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
Recommiting after fixup of 32-bit aliasing sign offset bug in DAGCombiner. * Simplify Consecutive Merge Store Candidate Search Now that address aliasing is much less conservative, push through simplified store merging search and chain alias analysis which only checks for parallel stores through the chain subgraph. This is cleaner as the separation of non-interfering loads/stores from the store-merging logic. When merging stores search up the chain through a single load, and finds all possible stores by looking down from through a load and a TokenFactor to all stores visited. This improves the quality of the output SelectionDAG and the output Codegen (save perhaps for some ARM cases where we correctly constructs wider loads, but then promotes them to float operations which appear but requires more expensive constant generation). Some minor peephole optimizations to deal with improved SubDAG shapes (listed below) Additional Minor Changes: 1. Finishes removing unused AliasLoad code 2. Unifies the chain aggregation in the merged stores across code paths 3. Re-add the Store node to the worklist after calling SimplifyDemandedBits. 4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is arbitrary, but seems sufficient to not cause regressions in tests. 5. Remove Chain dependencies of Memory operations on CopyfromReg nodes as these are captured by data dependence 6. Forward loads-store values through tokenfactors containing {CopyToReg,CopyFromReg} Values. 7. Peephole to convert buildvector of extract_vector_elt to extract_subvector if possible (see CodeGen/AArch64/store-merge.ll) 8. Store merging for the ARM target is restricted to 32-bit as some in some contexts invalid 64-bit operations are being generated. This can be removed once appropriate checks are added. This finishes the change Matt Arsenault started in r246307 and jyknight's original patch. Many tests required some changes as memory operations are now reorderable, improving load-store forwarding. One test in particular is worth noting: CodeGen/PowerPC/ppc64-align-long-double.ll - Improved load-store forwarding converts a load-store pair into a parallel store and a memory-realized bitcast of the same value. However, because we lose the sharing of the explicit and implicit store values we must create another local store. A similar transformation happens before SelectionDAG as well. Reviewers: arsenm, hfinkel, tstellarAMD, jyknight, nhaehnle llvm-svn: 296252 |
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Nirav Dave | 93f9d5ce04 |
Revert "In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled."
This reverts commit r293893 which is miscompiling lua on ARM and bootstrapping for x86-windows. llvm-svn: 293915 |
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Nirav Dave | 4442667fc5 |
In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
Recommiting after fixing X86 inc/dec chain bug. * Simplify Consecutive Merge Store Candidate Search Now that address aliasing is much less conservative, push through simplified store merging search and chain alias analysis which only checks for parallel stores through the chain subgraph. This is cleaner as the separation of non-interfering loads/stores from the store-merging logic. When merging stores search up the chain through a single load, and finds all possible stores by looking down from through a load and a TokenFactor to all stores visited. This improves the quality of the output SelectionDAG and the output Codegen (save perhaps for some ARM cases where we correctly constructs wider loads, but then promotes them to float operations which appear but requires more expensive constant generation). Some minor peephole optimizations to deal with improved SubDAG shapes (listed below) Additional Minor Changes: 1. Finishes removing unused AliasLoad code 2. Unifies the chain aggregation in the merged stores across code paths 3. Re-add the Store node to the worklist after calling SimplifyDemandedBits. 4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is arbitrary, but seems sufficient to not cause regressions in tests. 5. Remove Chain dependencies of Memory operations on CopyfromReg nodes as these are captured by data dependence 6. Forward loads-store values through tokenfactors containing {CopyToReg,CopyFromReg} Values. 7. Peephole to convert buildvector of extract_vector_elt to extract_subvector if possible (see CodeGen/AArch64/store-merge.ll) 8. Store merging for the ARM target is restricted to 32-bit as some in some contexts invalid 64-bit operations are being generated. This can be removed once appropriate checks are added. This finishes the change Matt Arsenault started in r246307 and jyknight's original patch. Many tests required some changes as memory operations are now reorderable, improving load-store forwarding. One test in particular is worth noting: CodeGen/PowerPC/ppc64-align-long-double.ll - Improved load-store forwarding converts a load-store pair into a parallel store and a memory-realized bitcast of the same value. However, because we lose the sharing of the explicit and implicit store values we must create another local store. A similar transformation happens before SelectionDAG as well. Reviewers: arsenm, hfinkel, tstellarAMD, jyknight, nhaehnle llvm-svn: 293893 |
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Nirav Dave | d32a421f75 |
Revert "In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled."
This reverts commit r293184 which is failing in LTO builds llvm-svn: 293188 |
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Nirav Dave | de6516c466 |
In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
* Simplify Consecutive Merge Store Candidate Search Now that address aliasing is much less conservative, push through simplified store merging search and chain alias analysis which only checks for parallel stores through the chain subgraph. This is cleaner as the separation of non-interfering loads/stores from the store-merging logic. When merging stores search up the chain through a single load, and finds all possible stores by looking down from through a load and a TokenFactor to all stores visited. This improves the quality of the output SelectionDAG and the output Codegen (save perhaps for some ARM cases where we correctly constructs wider loads, but then promotes them to float operations which appear but requires more expensive constant generation). Some minor peephole optimizations to deal with improved SubDAG shapes (listed below) Additional Minor Changes: 1. Finishes removing unused AliasLoad code 2. Unifies the chain aggregation in the merged stores across code paths 3. Re-add the Store node to the worklist after calling SimplifyDemandedBits. 4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is arbitrary, but seems sufficient to not cause regressions in tests. 5. Remove Chain dependencies of Memory operations on CopyfromReg nodes as these are captured by data dependence 6. Forward loads-store values through tokenfactors containing {CopyToReg,CopyFromReg} Values. 7. Peephole to convert buildvector of extract_vector_elt to extract_subvector if possible (see CodeGen/AArch64/store-merge.ll) 8. Store merging for the ARM target is restricted to 32-bit as some in some contexts invalid 64-bit operations are being generated. This can be removed once appropriate checks are added. This finishes the change Matt Arsenault started in r246307 and jyknight's original patch. Many tests required some changes as memory operations are now reorderable, improving load-store forwarding. One test in particular is worth noting: CodeGen/PowerPC/ppc64-align-long-double.ll - Improved load-store forwarding converts a load-store pair into a parallel store and a memory-realized bitcast of the same value. However, because we lose the sharing of the explicit and implicit store values we must create another local store. A similar transformation happens before SelectionDAG as well. Reviewers: arsenm, hfinkel, tstellarAMD, jyknight, nhaehnle llvm-svn: 293184 |
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Nirav Dave | f5bf03c7ef |
Revert "In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled."
Reverting due to ARM MCJIT and MIPS LLD error. This reverts commit r289659. llvm-svn: 289667 |
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Nirav Dave | 8527ab0ad2 |
In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
Retrying after fixing after removing load-store factoring through token factors in favor of improved token factor operand pruning Simplify Consecutive Merge Store Candidate Search Now that address aliasing is much less conservative, push through simplified store merging search which only checks for parallel stores through the chain subgraph. This is cleaner as the separation of non-interfering loads/stores from the store-merging logic. Whem merging stores, search up the chain through a single load, and finds all possible stores by looking down from through a load and a TokenFactor to all stores visited. This improves the quality of the output SelectionDAG and generally the output CodeGen (with some exceptions). Additional Minor Changes: 1. Finishes removing unused AliasLoad code 2. Unifies the the chain aggregation in the merged stores across code paths 3. Re-add the Store node to the worklist after calling SimplifyDemandedBits. 4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is arbitrary, but seemed sufficient to not cause regressions in tests. This finishes the change Matt Arsenault started in r246307 and jyknight's original patch. Many tests required some changes as memory operations are now reorderable. Some tests relying on the order were changed to use volatile memory operations Noteworthy tests: CodeGen/AArch64/argument-blocks.ll - It's not entirely clear what the test_varargs_stackalign test is supposed to be asserting, but the new code looks right. CodeGen/AArch64/arm64-memset-inline.lli - CodeGen/AArch64/arm64-stur.ll - CodeGen/ARM/memset-inline.ll - The backend now generates *worse* code due to store merging succeeding, as we do do a 16-byte constant-zero store efficiently. CodeGen/AArch64/merge-store.ll - Improved, but there still seems to be an extraneous vector insert from an element to itself? CodeGen/PowerPC/ppc64-align-long-double.ll - Worse code emitted in this case, due to the improved store->load forwarding. CodeGen/X86/dag-merge-fast-accesses.ll - CodeGen/X86/MergeConsecutiveStores.ll - CodeGen/X86/stores-merging.ll - CodeGen/Mips/load-store-left-right.ll - Restored correct merging of non-aligned stores CodeGen/AMDGPU/promote-alloca-stored-pointer-value.ll - Improved. Correctly merges buffer_store_dword calls CodeGen/AMDGPU/si-triv-disjoint-mem-access.ll - Improved. Sidesteps loading a stored value and merges two stores CodeGen/X86/pr18023.ll - This test has been removed, as it was asserting incorrect behavior. Non-volatile stores *CAN* be moved past volatile loads, and now are. CodeGen/X86/vector-idiv.ll - CodeGen/X86/vector-lzcnt-128.ll - It's basically impossible to tell what these tests are actually testing. But, looks like the code got better due to the memory operations being recognized as non-aliasing. CodeGen/X86/win32-eh.ll - Both loads of the securitycookie are now merged. Reviewers: arsenm, hfinkel, tstellarAMD, jyknight, nhaehnle Subscribers: wdng, nhaehnle, nemanjai, arsenm, weimingz, niravd, RKSimon, aemerson, qcolombet, dsanders, resistor, tstellarAMD, t.p.northover, spatel Differential Revision: https://reviews.llvm.org/D14834 llvm-svn: 289659 |
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Nirav Dave | bedb5d906c |
Revert "In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled."
This reverts commit r289221 which appears to be triggering an assertion llvm-svn: 289226 |
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Nirav Dave | fd51ff4fd8 |
In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
Retrying after fixing overly aggressive load-store forwarding optimization. Simplify Consecutive Merge Store Candidate Search Now that address aliasing is much less conservative, push through simplified store merging search which only checks for parallel stores through the chain subgraph. This is cleaner as the separation of non-interfering loads/stores from the store-merging logic. Whem merging stores, search up the chain through a single load, and finds all possible stores by looking down from through a load and a TokenFactor to all stores visited. This improves the quality of the output SelectionDAG and generally the output CodeGen (with some exceptions). Additional Minor Changes: 1. Finishes removing unused AliasLoad code 2. Unifies the the chain aggregation in the merged stores across code paths 3. Re-add the Store node to the worklist after calling SimplifyDemandedBits. 4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is arbitrary, but seemed sufficient to not cause regressions in tests. This finishes the change Matt Arsenault started in r246307 and jyknight's original patch. Many tests required some changes as memory operations are now reorderable. Some tests relying on the order were changed to use volatile memory operations Noteworthy tests: CodeGen/AArch64/argument-blocks.ll - It's not entirely clear what the test_varargs_stackalign test is supposed to be asserting, but the new code looks right. CodeGen/AArch64/arm64-memset-inline.lli - CodeGen/AArch64/arm64-stur.ll - CodeGen/ARM/memset-inline.ll - The backend now generates *worse* code due to store merging succeeding, as we do do a 16-byte constant-zero store efficiently. CodeGen/AArch64/merge-store.ll - Improved, but there still seems to be an extraneous vector insert from an element to itself? CodeGen/PowerPC/ppc64-align-long-double.ll - Worse code emitted in this case, due to the improved store->load forwarding. CodeGen/X86/dag-merge-fast-accesses.ll - CodeGen/X86/MergeConsecutiveStores.ll - CodeGen/X86/stores-merging.ll - CodeGen/Mips/load-store-left-right.ll - Restored correct merging of non-aligned stores CodeGen/AMDGPU/promote-alloca-stored-pointer-value.ll - Improved. Correctly merges buffer_store_dword calls CodeGen/AMDGPU/si-triv-disjoint-mem-access.ll - Improved. Sidesteps loading a stored value and merges two stores CodeGen/X86/pr18023.ll - This test has been removed, as it was asserting incorrect behavior. Non-volatile stores *CAN* be moved past volatile loads, and now are. CodeGen/X86/vector-idiv.ll - CodeGen/X86/vector-lzcnt-128.ll - It's basically impossible to tell what these tests are actually testing. But, looks like the code got better due to the memory operations being recognized as non-aliasing. CodeGen/X86/win32-eh.ll - Both loads of the securitycookie are now merged. Reviewers: arsenm, hfinkel, tstellarAMD, jyknight, nhaehnle Subscribers: wdng, nhaehnle, nemanjai, arsenm, weimingz, niravd, RKSimon, aemerson, qcolombet, dsanders, resistor, tstellarAMD, t.p.northover, spatel Differential Revision: https://reviews.llvm.org/D14834 llvm-svn: 289221 |
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Nirav Dave | a81682aad4 |
Revert "In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled."
This reverts commit r284151 which appears to be triggering a LTO failures on Hexagon llvm-svn: 284157 |
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Nirav Dave | 4b36957243 |
In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
Retrying after upstream changes. Simplify Consecutive Merge Store Candidate Search Now that address aliasing is much less conservative, push through simplified store merging search which only checks for parallel stores through the chain subgraph. This is cleaner as the separation of non-interfering loads/stores from the store-merging logic. Whem merging stores, search up the chain through a single load, and finds all possible stores by looking down from through a load and a TokenFactor to all stores visited. This improves the quality of the output SelectionDAG and generally the output CodeGen (with some exceptions). Additional Minor Changes: 1. Finishes removing unused AliasLoad code 2. Unifies the the chain aggregation in the merged stores across code paths 3. Re-add the Store node to the worklist after calling SimplifyDemandedBits. 4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is arbitrary, but seemed sufficient to not cause regressions in tests. This finishes the change Matt Arsenault started in r246307 and jyknight's original patch. Many tests required some changes as memory operations are now reorderable. Some tests relying on the order were changed to use volatile memory operations Noteworthy tests: CodeGen/AArch64/argument-blocks.ll - It's not entirely clear what the test_varargs_stackalign test is supposed to be asserting, but the new code looks right. CodeGen/AArch64/arm64-memset-inline.lli - CodeGen/AArch64/arm64-stur.ll - CodeGen/ARM/memset-inline.ll - The backend now generates *worse* code due to store merging succeeding, as we do do a 16-byte constant-zero store efficiently. CodeGen/AArch64/merge-store.ll - Improved, but there still seems to be an extraneous vector insert from an element to itself? CodeGen/PowerPC/ppc64-align-long-double.ll - Worse code emitted in this case, due to the improved store->load forwarding. CodeGen/X86/dag-merge-fast-accesses.ll - CodeGen/X86/MergeConsecutiveStores.ll - CodeGen/X86/stores-merging.ll - CodeGen/Mips/load-store-left-right.ll - Restored correct merging of non-aligned stores CodeGen/AMDGPU/promote-alloca-stored-pointer-value.ll - Improved. Correctly merges buffer_store_dword calls CodeGen/AMDGPU/si-triv-disjoint-mem-access.ll - Improved. Sidesteps loading a stored value and merges two stores CodeGen/X86/pr18023.ll - This test has been removed, as it was asserting incorrect behavior. Non-volatile stores *CAN* be moved past volatile loads, and now are. CodeGen/X86/vector-idiv.ll - CodeGen/X86/vector-lzcnt-128.ll - It's basically impossible to tell what these tests are actually testing. But, looks like the code got better due to the memory operations being recognized as non-aliasing. CodeGen/X86/win32-eh.ll - Both loads of the securitycookie are now merged. CodeGen/AMDGPU/vgpr-spill-emergency-stack-slot-compute.ll - This test appears to work but no longer exhibits the spill behavior. Reviewers: arsenm, hfinkel, tstellarAMD, jyknight, nhaehnle Subscribers: wdng, nhaehnle, nemanjai, arsenm, weimingz, niravd, RKSimon, aemerson, qcolombet, dsanders, resistor, tstellarAMD, t.p.northover, spatel Differential Revision: https://reviews.llvm.org/D14834 llvm-svn: 284151 |
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Nirav Dave | e524f50882 |
Revert "In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled."
This reverts commit r282600 due to test failues with MCJIT llvm-svn: 282604 |
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Nirav Dave | e17e055b75 |
In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
Simplify Consecutive Merge Store Candidate Search Now that address aliasing is much less conservative, push through simplified store merging search which only checks for parallel stores through the chain subgraph. This is cleaner as the separation of non-interfering loads/stores from the store-merging logic. Whem merging stores, search up the chain through a single load, and finds all possible stores by looking down from through a load and a TokenFactor to all stores visited. This improves the quality of the output SelectionDAG and generally the output CodeGen (with some exceptions). Additional Minor Changes: 1. Finishes removing unused AliasLoad code 2. Unifies the the chain aggregation in the merged stores across code paths 3. Re-add the Store node to the worklist after calling SimplifyDemandedBits. 4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is arbitrary, but seemed sufficient to not cause regressions in tests. This finishes the change Matt Arsenault started in r246307 and jyknight's original patch. Many tests required some changes as memory operations are now reorderable. Some tests relying on the order were changed to use volatile memory operations Noteworthy tests: CodeGen/AArch64/argument-blocks.ll - It's not entirely clear what the test_varargs_stackalign test is supposed to be asserting, but the new code looks right. CodeGen/AArch64/arm64-memset-inline.lli - CodeGen/AArch64/arm64-stur.ll - CodeGen/ARM/memset-inline.ll - The backend now generates *worse* code due to store merging succeeding, as we do do a 16-byte constant-zero store efficiently. CodeGen/AArch64/merge-store.ll - Improved, but there still seems to be an extraneous vector insert from an element to itself? CodeGen/PowerPC/ppc64-align-long-double.ll - Worse code emitted in this case, due to the improved store->load forwarding. CodeGen/X86/dag-merge-fast-accesses.ll - CodeGen/X86/MergeConsecutiveStores.ll - CodeGen/X86/stores-merging.ll - CodeGen/Mips/load-store-left-right.ll - Restored correct merging of non-aligned stores CodeGen/AMDGPU/promote-alloca-stored-pointer-value.ll - Improved. Correctly merges buffer_store_dword calls CodeGen/AMDGPU/si-triv-disjoint-mem-access.ll - Improved. Sidesteps loading a stored value and merges two stores CodeGen/X86/pr18023.ll - This test has been removed, as it was asserting incorrect behavior. Non-volatile stores *CAN* be moved past volatile loads, and now are. CodeGen/X86/vector-idiv.ll - CodeGen/X86/vector-lzcnt-128.ll - It's basically impossible to tell what these tests are actually testing. But, looks like the code got better due to the memory operations being recognized as non-aliasing. CodeGen/X86/win32-eh.ll - Both loads of the securitycookie are now merged. CodeGen/AMDGPU/vgpr-spill-emergency-stack-slot-compute.ll - This test appears to work but no longer exhibits the spill behavior. Reviewers: arsenm, hfinkel, tstellarAMD, nhaehnle, jyknight Subscribers: wdng, nhaehnle, nemanjai, arsenm, weimingz, niravd, RKSimon, aemerson, qcolombet, resistor, tstellarAMD, t.p.northover, spatel Differential Revision: https://reviews.llvm.org/D14834 llvm-svn: 282600 |
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Nirav Dave | fa250cad37 |
Prevent construction of cycle in DAG store merge
When merging stores in DAGCombiner, add check to ensure that no dependenices exist that would cause the construction of a cycle in our DAG. This may happen if one store has a data dependence on another instruction (e.g. a load) which itself has a (chain) dependence on another store being merged. These stores cannot be merged safely and doing so results in a cycle that is discovered in LegalizeDAG. This test is only done in cases where Antialias analysis is used (UseAA) as non-AA store merge candidates will be merged logically after all loads which have been checked to not alias. Reviewers: ahatanak, spatel, niravd, arsenm, hfinkel, tstellarAMD, jyknight Subscribers: llvm-commits, tberghammer, danalbert, srhines Differential Revision: http://reviews.llvm.org/D18336 llvm-svn: 264461 |