[ARM] Convert some tests to opaque pointers (NFC)

[ARM] Simplify address calculation for NEON load/store

The patch attempts to optimize a sequence of SIMD loads from the same
base pointer:

%0 = gep float*, float* base, i32 4
%1 = bitcast f

[ARM] Simplify address calculation for NEON load/store

The patch attempts to optimize a sequence of SIMD loads from the same
base pointer:

%0 = gep float*, float* base, i32 4
%1 = bitcast float* %0 to <4 x float>*
%2 = load <4 x float>, <4 x float>* %1
...
%n1 = gep float*, float* base, i32 N
%n2 = bitcast float* %n1 to <4 x float>*
%n3 = load <4 x float>, <4 x float>* %n2

For AArch64 the compiler generates a sequence of LDR Qt, [Xn, #16].
However, 32-bit NEON VLD1/VST1 lack the [Wn, #imm] addressing mode, so
the address is computed before every ld/st instruction:

add r2, r0, #32
add r0, r0, #16
vld1.32 {d18, d19}, [r2]
vld1.32 {d22, d23}, [r0]

This can be improved by computing address for the first load, and then
using a post-indexed form of VLD1/VST1 to load the rest:

add r0, r0, #16
vld1.32 {d18, d19}, [r0]!
vld1.32 {d22, d23}, [r0]

In order to do that, the patch adds more patterns to DAGCombine:

- (load (add ptr inc1)) and (add ptr inc2) are now folded if inc1
and inc2 are constants.

- (or ptr inc) is now recognized as a pointer increment if ptr is
sufficiently aligned.

In addition to that, we now search for all possible base updates and
then pick the best one.

Differential Revision: https://reviews.llvm.org/D108988

show more ...

OpaquePtr: Bulk update tests to use typed sret

[SelectionDAG] Don't promote the alignment of allocas beyond the stack alignment.

allocas in LLVM IR have a specified alignment. When that alignment is
specified, the alloca has at least that alignm

[SelectionDAG] Don't promote the alignment of allocas beyond the stack alignment.

allocas in LLVM IR have a specified alignment. When that alignment is
specified, the alloca has at least that alignment at runtime.

If the specified type of the alloca has a higher preferred alignment,
SelectionDAG currently ignores that specified alignment, and increases
the alignment. It does this even if it would trigger stack realignment.
I don't think this makes sense, so this patch changes that.

I was looking into this for SVE in particular: for SVE, overaligning
vscale'ed types is extra expensive because it requires realigning the
stack multiple times, or using dynamic allocation. (This currently isn't
implemented.)

I updated the expected assembly for a couple tests; in particular, for
arg-copy-elide.ll, the optimization in question does not increase the
alignment the way SelectionDAG normally would. For the rest, I just
increased the specified alignment on the allocas to match what
SelectionDAG was inferring.

Differential Revision: https://reviews.llvm.org/D79532

show more ...

[DAGCombine] Disable finding better chains for stores at O0

Unoptimized IR can have linear sequences of stores to an array, where the
initial GEP for the first store is formed from the pointer to th

[DAGCombine] Disable finding better chains for stores at O0

Unoptimized IR can have linear sequences of stores to an array, where the
initial GEP for the first store is formed from the pointer to the array, and the
GEP for each store after the first is formed from the previous GEP with some
offset in an inductive fashion.

The (large) resulting DAG when analyzed by DAGCombine undergoes an excessive
number of combines as each store node is examined every time its' offset node
is combined with any child of the offset. One of the transformations is
findBetterNeighborChains which assists MergeConsecutiveStores. The former
relies on repeated chain walking to do its' work, however MergeConsecutiveStores
is disabled at O0 which makes the transformation redundant.

Any optimization level other than O0 would invoke InstCombine which would
resolve the chain of GEPs into flat base + offset GEP for each store which
does not exhibit the repeated examination of each store to the array.

Disabling this optimization fixes an excessive compile time issue (30~ minutes
for the test case provided) at O0.

Reviewers: niravd, craig.topper, t.p.northover

Differential Revision: https://reviews.llvm.org/D40193

llvm-svn: 319142

show more ...

ARM: handle post-indexed NEON ops where the offset isn't the access width.

Before, we assumed that any ConstantInt offset was precisely the access width,
so we could use the "[rN]!" form. ISelLoweri

ARM: handle post-indexed NEON ops where the offset isn't the access width.

Before, we assumed that any ConstantInt offset was precisely the access width,
so we could use the "[rN]!" form. ISelLowering only ever created that kind, but
further simplification during combining could lead to unexpected constants and
incorrect codegen.

Should fix PR32658.

llvm-svn: 300878

show more ...

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

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

show more ...

[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
severa

[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

show more ...

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 St

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

show more ...

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: 296

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

show more ...

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 St

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

show more ...

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:

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

show more ...

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

N

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

show more ...

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

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, p

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

show more ...

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

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 o

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

show more ...

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

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 Candi

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

show more ...

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

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 alia

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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[DAGCombiner] Do not remove the load of stored values when optimizations are disabled

This combiner breaks debug experience and should not be run when optimizations are disabled.

For example:
int

[DAGCombiner] Do not remove the load of stored values when optimizations are disabled

This combiner breaks debug experience and should not be run when optimizations are disabled.

For example:
int main() {
int j = 0;
j += 2;
if (j == 2)
return 0;
return 5;
}
When debugging this code compiled in /O0, it should be valid to break at line "j+=2;" and edit the value of j. It should change the return value of the function.

Differential Revision: https://reviews.llvm.org/D19268

llvm-svn: 284014

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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

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 th

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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[opaque pointer type] Add textual IR support for explicit type parameter to load instruction

Essentially the same as the GEP change in r230786.

A similar migration script can be used to update test

[opaque pointer type] Add textual IR support for explicit type parameter to load instruction

Essentially the same as the GEP change in r230786.

A similar migration script can be used to update test cases, though a few more
test case improvements/changes were required this time around: (r229269-r229278)

import fileinput
import sys
import re

pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)")

for line in sys.stdin:
sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line))

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7649

llvm-svn: 230794

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