Summary: AArch64 LLVM assembler emits add instruction without shift bit to calculate the higher 12-bit address of TLS variables in local exec model. This generates wrong code sequence to access TLS variables with thread offset larger than 0x1000.
Reviewers: t.p.northover, peter.smith, rovka
Subscribers: salim.nasser, aemerson, llvm-commits, rengolin
Differential Revision: https://reviews.llvm.org/D24702
llvm-svn: 282661
This is a step toward statically allocate InstructionMapping. Like the
previous few commits, the goal is to move toward a TableGen'ed like
structure with no dynamic allocation at all.
This should already improve compile time by getting rid of a bunch of
memmove of SmallVectors.
llvm-svn: 282643
Implement 'retn' simply by aliasing it to the relevant 'ret' instruction
Commit on behalf of coby
Differential Revision: https://reviews.llvm.org/D24346
llvm-svn: 282601
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
Summary:
This adds the AVRMCTargetDesc file in tree. It allows creation of the
core classes used in the backend.
Reviewers: arsenm, kparzysz
Subscribers: wdng, beanz, mgorny
Differential Revision: https://reviews.llvm.org/D25023
llvm-svn: 282597
The previous data layout caused issues when dealing with atomics.
Foe example, it is illegal to load a 16-bit value with less than 16-bits
of alignment.
This changes the data layout so that all types are aligned by at least
their own width.
Interestingly, this also _slightly_ decreased register pressure in some
cases.
llvm-svn: 282587
The KORTEST was introduced due to a bug where a TEST instruction used a K register.
but, turns out that the opposite case of KORTEST using a GPR is now happening
The change removes the KORTEST flow and adds a COPY instruction from the K reg to a GPR.
Differential Revision: https://reviews.llvm.org/D24953
llvm-svn: 282580
This commit enables more unrolling for SystemZ by implementing the
SystemZTargetTransformInfo::getUnrollingPreferences() method.
It has been found that it is better to only unroll moderately, so the
DefaultUnrollRuntimeCount has been moved into UnrollingPreferences in order
to set this to a lower value for SystemZ (4).
Reviewers: Evgeny Stupachenko, Ulrich Weigand.
https://reviews.llvm.org/D24451
llvm-svn: 282570
Another step toward TableGen'ed like structure for the RegisterBankInfo
of AArch64. By doing this, we also save a bit of compile time for the
exact same output.
llvm-svn: 282550
The 'or' case shows up in copysign. The copysign code also had
redundant checking for a scalar zero operand with 'and', so I
removed that.
I'm not sure how to test vector 'and', 'andn', and 'xor' yet,
but it seems better to just include all of the logic ops since
we're fixing 'or' anyway.
llvm-svn: 282546
Summary:
The current implementation of isConstantPhysReg() checks for defs of
physical registers to determine if they are constant. Some
architectures (e.g. AArch64 XZR/WZR) have registers that are constant
and may be used as destinations to indicate the generated value is
discarded, preventing isConstantPhysReg() from returning true. This
change adds a TargetRegisterInfo hook that overrides the no defs check
for cases such as this.
Reviewers: MatzeB, qcolombet, t.p.northover, jmolloy
Subscribers: junbuml, aemerson, mcrosier, rengolin
Differential Revision: https://reviews.llvm.org/D24570
llvm-svn: 282543
A landing pad can have live-in registers that are defined by the runtime,
not the program (exception pointer register and exception selector
register). Make sure to recognize that case and not link these registers
with any defs in the program.
Each landing pad will have phi nodes added at the beginning to provide
definitions of these registers, but the uses of those phi nodes will not
have any reaching defs.
llvm-svn: 282519
Disable tail calls while the remaining bugs are fixed. Enable only for tests.
Reviewers: vkalintiris
Differential Review: https://reviews.llvm.org/D24912
llvm-svn: 282487
Add rsqrt.[ds], recip.[ds] for MIPS. Correct the microMIPS definitions for
architecture support and register usage.
Reviewers: vkalintiris, zoran.jovanoic
Differential Review: https://reviews.llvm.org/D24499
llvm-svn: 282485
This patch corresponds to review:
https://reviews.llvm.org/D24396
This patch adds support for the "vector count trailing zeroes",
"vector compare not equal" and "vector compare not equal or zero instructions"
as well as "scalar count trailing zeroes" instructions. It also changes the
vector negation to use XXLNOR (when VSX is enabled) so as not to increase
register pressure (previously this was done with a splat immediate of all
ones followed by an XXLXOR). This was done because the altivec.h
builtins (patch to follow) use vector negation and the use of an additional
register for the splat immediate is not optimal.
llvm-svn: 282478
When we have dynamic allocas we have a frame pointer, and
when we're lowering frame indexes we should make sure we use it.
Patch by Jacob Gravelle
Differential Revision: https://reviews.llvm.org/D24889
llvm-svn: 282442
Don't match the UXTW extended reg forms of ADD/ADDS/SUB/SUBS if the
32-bit to 64-bit zero-extend can be done for free by taking advantage
of the 32-bit defining instruction zeroing the upper 32-bits of the X
register destination. This enables better instruction selection in a
few cases, such as:
sub x0, xzr, x8
instead of:
mov x8, xzr
sub x0, x8, w9, uxtw
madd x0, x1, x1, x8
instead of:
mul x9, x1, x1
add x0, x9, w8, uxtw
cmp x2, x8
instead of:
sub x8, x2, w8, uxtw
cmp x8, #0
add x0, x8, x1, lsl #3
instead of:
lsl x9, x1, #3
add x0, x9, w8, uxtw
Reviewers: t.p.northover, jmolloy
Subscribers: mcrosier, aemerson, llvm-commits, rengolin
Differential Revision: https://reviews.llvm.org/D24747
llvm-svn: 282413
Many high-performance processors have a dedicated branch predictor for
indirect branches, commonly used with jump tables. As sophisticated as such
branch predictors are, they tend to have well defined limits beyond which
their effectiveness is hampered or even nullified. One such limit is the
number of possible destinations for a given indirect branches that such
branch predictors can handle.
This patch considers a limit that a target may set to the number of
destination addresses in a jump table.
Patch by: Evandro Menezes <e.menezes@samsung.com>, Aditya Kumar
<aditya.k7@samsung.com>, Sebastian Pop <s.pop@samsung.com>.
Differential revision: https://reviews.llvm.org/D21940
llvm-svn: 282412
If a constant is unamed_addr and is only used within one function, we can save
on the code size and runtime cost of an indirection by changing the global's storage
to inside the constant pool. For example, instead of:
ldr r0, .CPI0
bl printf
bx lr
.CPI0: &format_string
format_string: .asciz "hello, world!\n"
We can emit:
adr r0, .CPI0
bl printf
bx lr
.CPI0: .asciz "hello, world!\n"
This can cause significant code size savings when many small strings are used in one
function (4 bytes per string).
This recommit contains fixes for a nasty bug related to fast-isel fallback - because
fast-isel doesn't know about this optimization, if it runs and emits references to
a string that we inline (because fast-isel fell back to SDAG) we will end up
with an inlined string and also an out-of-line string, and we won't emit the
out-of-line string, causing backend failures.
It also contains fixes for emitting .text relocations which made the sanitizer
bots unhappy.
llvm-svn: 282387
Summary:
Replace a LEA instruction of the form 'lea (%esp), %ebx' --> 'mov %esp, %ebx'
MOV is preferable over LEA because usually there are more issue-slots available to execute MOVs than LEAs. Latest processors also support zero-latency MOVs.
Fixes pr29022.
Reviewers: hfinkel, delena, igorb, myatsina, mkuper
Differential Revision: https://reviews.llvm.org/D24705
llvm-svn: 282385
Lei Liu