Lower a = b * C where C = (2^n + 1) * 2^m to
add w0, w0, w0, lsl n
lsl w0, w0, m
Differential Revision: https://reviews.llvm.org/D229245
llvm-svn: 287019
Implement the Newton series for square root, its reciprocal and reciprocal
natively using the specialized instructions in AArch64 to perform each
series iteration.
Differential revision: https://reviews.llvm.org/D26518
llvm-svn: 286907
Summary:
Replace a splat of zeros to a vector store by scalar stores of WZR/XZR.
The load store optimizer pass will merge them to store pair stores.
This should be better than a movi to create the vector zero followed by
a vector store if the zero constant is not re-used, since one
instructions and one register live range will be removed.
For example, the final generated code should be:
stp xzr, xzr, [x0]
instead of:
movi v0.2d, #0
str q0, [x0]
Reviewers: t.p.northover, mcrosier, MatzeB, jmolloy
Subscribers: aemerson, rengolin, llvm-commits
Differential Revision: https://reviews.llvm.org/D26561
llvm-svn: 286875
Summary:
Fix off-by-one indexing error in loop checking that inserted value was a
splat vector.
Add code to check that INSERT_VECTOR_ELT nodes constructing the splat
vector have the expected constant index values.
Reviewers: t.p.northover, jmolloy, mcrosier
Subscribers: aemerson, llvm-commits, rengolin
Differential Revision: https://reviews.llvm.org/D26409
llvm-svn: 286616
This is a partial revert of r244615 (http://reviews.llvm.org/D11942),
which caused a major regression in debug info quality.
Turning the artificial __MergedGlobal symbols into private symbols
(l__MergedGlobal) means that the linker will not include them in the
symbol table of the final executable. Without a symbol table entry
dsymutil is not be able to process the debug info for any of the
merged globals and thus drops the debug info for all of them.
This patch is enabling the old behavior for all MachO targets while
leaving all other targets unaffected.
rdar://problem/29160481
https://reviews.llvm.org/D26531
llvm-svn: 286607
addSchedBarrierDeps() is supposed to add use operands to the ExitSU
node. The current implementation adds uses for calls/barrier instruction
and the MBB live-outs in all other cases. The use
operands of conditional jump instructions were missed.
Also added code to macrofusion to set the latencies between nodes to
zero to avoid problems with the fusing nodes lingering around in the
pending list now.
Differential Revision: https://reviews.llvm.org/D25140
llvm-svn: 286544
There is no need to track dependencies for constant physregs, as they
don't change their value no matter in what order you read/write to them.
Differential Revision: https://reviews.llvm.org/D26221
llvm-svn: 286526
When copying to/from a constant register interferences can be ignored.
Also update the documentation for isConstantPhysReg() to make it more
obvious that this transformation is valid.
Differential Revision: https://reviews.llvm.org/D26106
llvm-svn: 286503
Under -enable-unsafe-fp-math, SELECT_CC lowering in AArch64
transforms floating point comparisons of the form "a == 0.0 ? 0.0 : x" to
"a == 0.0 ? a : x". But it incorrectly assumes that 'x' and 'a' have
the same type which can lead to a wrong CSEL node that crashes later
due to nonsensical copies.
Differential Revision: https://reviews.llvm.org/D26394
llvm-svn: 286231
Self-referencing PHI nodes need their destination operands to be constrained
because nothing else is likely to do so. For now we just pick a register class
naively.
Patch mostly by Ahmed again.
llvm-svn: 286183
Summary:
Some vector loads and stores generated from AArch64 intrinsics alias each other
unnecessarily, preventing better scheduling. We just need to transfer memory
operands during lowering.
Reviewers: mcrosier, t.p.northover, jmolloy
Subscribers: aemerson, rengolin, llvm-commits
Differential Revision: https://reviews.llvm.org/D26313
llvm-svn: 286168
Add an option to allow easier experimentation by target maintainers with the
minimum number of entries to create jump tables. Also clarify the name of
the other existing option governing the creation of jump tables.
Differential revision: https://reviews.llvm.org/D25883
llvm-svn: 285104
When there's a tie between partitionings of jump tables, consider also cases
that result in no jump tables, but in one or a few cases. The motivation is
that many contemporary processors typically perform case switches fairly
quickly.
Differential revision: https://reviews.llvm.org/D25212
llvm-svn: 285099
Add support for estimating the square root or its reciprocal and division or
reciprocal using the combiner generic Newton series.
Differential revision: https://reviews.llvm.org/D25291
llvm-svn: 284986
Transform `a == 0.0 ? 0.0 : x` to `a == 0.0 ? a : x` and `a != 0.0 ? x : 0.0`
to `a != 0.0 ? x : a` to avoid materializing 0.0 for FCSEL, since it does not
have to be materialized beforehand for FCMP, as it has a form that has 0.0
as an implicit operand.
Differential Revision: https://reviews.llvm.org/D24808
llvm-svn: 284531
AArch64 actually supports many 8-bit operations under the definition used by
GlobalISel: the designated information-carrying bits of a GPR32 get the right
value if you just use the normal 32-bit instruction.
llvm-svn: 284526
The previous names were both misleading (the MachineLegalizer actually
contained the info tables) and inconsistent with the selector & translator (in
having a "Machine") prefix. This should make everything sensible again.
The only functional change is the name of a couple of command-line options.
llvm-svn: 284287
Mostly this just means changing the triple from aarch64-apple-ios to the generic
aarch64--. Only one test needs more significant changes, but GlobalISel already
does the right thing so it's ok to just change the checks.
Differential Revision: https://reviews.llvm.org/D25532
llvm-svn: 284223
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
This allows RegBankSelect in greedy mode to get rid some of the cross
register bank copies when loads are involved in the chain of
computation.
llvm-svn: 284097
Chad Rosier