When working out whether we can see a compressible jump-table pattern during
ConstantIslands, we were stopping when we saw a debug instruction. Instead it's
better to keep iterating backwards to the first real instruction.
https://reviews.llvm.org/D142019
Alignment of an alloca in IR can be lower than the preferred alignment
on purpose, but this override essentially treats the preferred
alignment as the minimum alignment.
The patch changes this behavior to always use the specified
alignment. If alignment is not set explicitly in LLVM IR, it is set to
DL.getPrefTypeAlign(Ty) in computeAllocaDefaultAlign.
Tests are changed as well: explicit alignment is increased to match
the preferred alignment if it changes output, or omitted when it is
hard to determine the right value (e.g. for pointers, some structs, or
weird types).
Differential Revision: https://reviews.llvm.org/D135462
YAML specification does not allow keys duplication an a mapping. However, YAML
parser in LLVM does not have any check on that and uses only the last key entry.
In this change duplicated keys are merged to satisfy the spec.
Differential Revision: https://reviews.llvm.org/D141848
If this successor list is not correct, then branch-folding may
incorrectly think that the indirect target is dead and remove it. This
results in a dangling reference to the removed block as an operand to
the INLINEASM_BR, which later will get AsmPrinted into code that doesn't
assemble.
This was made more obvious by, but is not a regression of
https://reviews.llvm.org/D130316.
Fixes: https://github.com/llvm/llvm-project/issues/60346
Reviewed By: efriedma, void
Differential Revision: https://reviews.llvm.org/D142924
Currently, in TargetLowering, if the target does not support fminnum, we lower
to fminimum if neither operand could be a NaN. But this isn't quite correct
because fminnum and fminimum treat +/-0 differently; so, we need to prove that
one of the operands isn't a zero, or we don't have signed zeros.
Differential Revision: https://reviews.llvm.org/D143256
ValueTracking attempts to match compare+select patterns to FP min/max
operations, but it was created before the newer IEEE-754-2019
minimum/maximum ops were defined. Ie, matchSelectPattern() does not
account for the -0.0/+0.0 behavior that is specified in the newer
standard.
FMINIMUM/FMAXIMUM nodes were created to map to the newer standard:
/// FMINIMUM/FMAXIMUM - NaN-propagating minimum/maximum that also treat -0.0
/// as less than 0.0. While FMINNUM_IEEE/FMAXNUM_IEEE follow IEEE 754-2008
/// semantics, FMINIMUM/FMAXIMUM follow IEEE 754-2018 draft semantics.
We could adjust ValueTracking to deal with signed zero, but it seems like
a moot point given the divergent NaN behavior discussed in D143056, so just
delete this possibility to avoid bugs when converting IR to SDAG.
Differential Revision: https://reviews.llvm.org/D143106
If a chain of two selects share a true/false value and are controlled
by two setcc nodes, that are never both true, we can fold away one of
the selects. So, the following:
(select (setcc X, const0, eq), Y,
(select (setcc X, const1, eq), Z, Y))
Can be combined to:
select (setcc X, const1, eq) Z, Y
Differential Revision: https://reviews.llvm.org/D142535
When working out whether we can see a compressible jump-table pattern during
ConstantIslands, we were stopping when we saw a debug instruction. Instead it's
better to keep iterating backwards to the first real instruction.
These are essentially add/sub 1 with a clamping value.
AMDGPU has instructions for these. CUDA/HIP expose these as
atomicInc/atomicDec. Currently we use target intrinsics for these,
but those do no carry the ordering and syncscope. Add these to
atomicrmw so we can carry these and benefit from the regular
legalization processes.
Given a patch like D129506, using instructions not valid for the current
target feature set becomes an error. This means that emitting Arm
instructions in a Thumb target (or vice versa) becomes an error. When
running in Thumb mode only thumb thunks will be needed, and in Arm mode
only arm thunks are needed. This patch limits the emitted thunks to just
the ones valid for the current architecture.
Differential Revision: https://reviews.llvm.org/D129693
This makes most sense for isFNegFree targets, but shouldn't make
things worse without it. This avoids AMDGPU test regressions in a
future patch.
For some reason APFloat::compareAbsoluteValue is private, so compute
the neg of the constants.
This change switches both targets from using target specific CompilerBarrier nodes to the recently introduced generic MEMBARRIER instruction.
A couple things to call out.
First, this changes the assembly comment printed. I'm not sure this matters, but if it does, we can simply drop this patch. This is a minor clean up at best.
Second, the ordering operand on the target instruction appears to be unused. We could easily add ordering to the generic instruction, but since we don't seem to have a motivating case in tree, I simply dropped the ordering when selecting to the generic instruction.
Differential Revision: https://reviews.llvm.org/D141513
Follow-up for 4ece50737d5385fb80cfa23f5297d1111f8eed39 (D142027).
Assignment Tracking Analysis now always runs and is skipped internally if
assignment tracking is disabled. Update these tests to expect to see the
pass run.
Buildbot failure: https://lab.llvm.org/buildbot/#/builders/57/builds/24094
Issue #58168 describes the difficulty diagnosing stack size issues
identified by -Wframe-larger-than. For simple code, its easy to
understand the stack layout and where space is being allocated, but in
more complex programs, where code may be heavily inlined, unrolled, and
have duplicated code paths, it is no longer easy to manually inspect the
source program and understand where stack space can be attributed.
This patch implements a machine function pass that emits remarks with a
textual representation of stack slots, and also outputs any available
debug information to map source variables to those slots.
The new behavior can be used by adding `-Rpass-analysis=stack-frame-layout`
to the compiler invocation. Like other remarks the diagnostic
information can be saved to a file in a machine readable format by
adding -fsave-optimzation-record.
Fixes: #58168
Reviewed By: nickdesaulniers, thegameg
Differential Revision: https://reviews.llvm.org/D135488
IR is now always parsed in opaque pointer mode, unless
-opaque-pointers=0 is explicitly given. There is no automatic
detection of typed pointers anymore.
The -opaque-pointers=0 option is added to any remaining IR tests
that haven't been migrated yet.
Differential Revision: https://reviews.llvm.org/D141912
Issue #58168 describes the difficulty diagnosing stack size issues
identified by -Wframe-larger-than. For simple code, its easy to
understand the stack layout and where space is being allocated, but in
more complex programs, where code may be heavily inlined, unrolled, and
have duplicated code paths, it is no longer easy to manually inspect the
source program and understand where stack space can be attributed.
This patch implements a machine function pass that emits remarks with a
textual representation of stack slots, and also outputs any available
debug information to map source variables to those slots.
The new behavior can be used by adding `-Rpass-analysis=stack-frame-layout`
to the compiler invocation. Like other remarks the diagnostic
information can be saved to a file in a machine readable format by
adding -fsave-optimzation-record.
Fixes: #58168
Reviewed By: nickdesaulniers, thegameg
Differential Revision: https://reviews.llvm.org/D135488
If the dividend has leading zeros, we can use them to reduce the
size of the multiplier and avoid the fixup cases.
This patch is for scalars only, but we might be able to do this
for vectors in a follow up.
Differential Revision: https://reviews.llvm.org/D140750
These tests needn't use loads in their testing of dup and mul
instructions, and as the load changes the test may no longer test what
they are intending (as in D140069).
Address the inconsistency between FLT_ROUNDS_ and SET_ROUNDING SDAG
node. Rename FLT_ROUNDS_ to GET_ROUNDING and add llvm.get.rounding
intrinsic to replace flt.rounds.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D139507
Alignment of an alloca in IR can be lower than the preferred alignment
on purpose, but this override essentially treats the preferred
alignment as the minimum alignment.
The patch changes this behavior to always use the specified
alignment. If alignment is not set explicitly in LLVM IR, it is set to
DL.getPrefTypeAlign(Ty) in computeAllocaDefaultAlign.
Tests are changed as well: explicit alignment is increased to match
the preferred alignment if it changes output, or omitted when it is
hard to determine the right value (e.g. for pointers, some structs, or
weird types).
Differential Revision: https://reviews.llvm.org/D135462
Over the past day or so, i've took a large swing at our tests,
and reduced the number of tests that were still using the old syntax
from ~1800 to just 200.
Left to handle: (as it is seen in this patch)
* Transforms/LSR
* Transforms/CGP
* Transforms/TypePromotion
* Transforms/HardwareLoops
* Analysis/*
* some misc.
I think this is the right point to start actively refusing
to honor the old syntax, except for the old tests,
to prevent the old syntax from creeping back in.
Thus, let's add temporary default-off flag,
and if it is not passed refuse to accept old syntax.
The tests that still need porting are annotated with this flag.
Reviewed By: aeubanks
Differential Revision: https://reviews.llvm.org/D139647
This reverts commit 122efef8ee9be57055d204d52c38700fe933c033.
- Patch fixed to not reuse definitions from predecessors in EH landing pads.
- Late review suggestions (by MaskRay) have been addressed.
- M68k/pipeline.ll test updated.
- Init captures added in processBlock() to avoid capturing structured bindings.
- RISCV has this disabled for now.
Original commit message:
A new pass MachineLateInstrsCleanup is added to be run after PEI.
This is a simple pass that removes redundant and identical instructions
whenever found by scanning the MF once while keeping track of register
definitions in a map. These instructions are typically immediate loads
resulting from rematerialization, and address loads emitted by target in
eliminateFrameInde().
This is enabled by default, but a target could easily disable it by means of
'disablePass(&MachineLateInstrsCleanupID);'.
This late cleanup is naturally not "optimal" in removing instructions as it
is done by looking at phys-regs, but still quite effective. It would be
desirable to improve other parts of CodeGen and avoid these redundant
instructions in the first place, but there are no ideas for this yet.
Differential Revision: https://reviews.llvm.org/D123394
Reviewed By: RKSimon, foad, craig.topper, arsenm, asb
Currently per-function metadata consists of:
(start-pc, size, features)
This adds a new UAR feature and if it's set an additional element:
(start-pc, size, features, stack-args-size)
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D136078
Init captures added in processBlock() to avoid capturing structured bindings,
which caused the build problems (with clang).
RISCV has this disabled for now until problems relating to post RA pseudo
expansions are resolved.
A new pass MachineLateInstrsCleanup is added to be run after PEI.
This is a simple pass that removes redundant and identical instructions
whenever found by scanning the MF once while keeping track of register
definitions in a map. These instructions are typically immediate loads
resulting from rematerialization, and address loads emitted by target in
eliminateFrameInde().
This is enabled by default, but a target could easily disable it by means of
'disablePass(&MachineLateInstrsCleanupID);'.
This late cleanup is naturally not "optimal" in removing instructions as it
is done by looking at phys-regs, but still quite effective. It would be
desirable to improve other parts of CodeGen and avoid these redundant
instructions in the first place, but there are no ideas for this yet.
Differential Revision: https://reviews.llvm.org/D123394
Reviewed By: RKSimon, foad, craig.topper, arsenm, asb
As stated in
https://discourse.llvm.org/t/rfc-llc-add-expandlargeintfpconvert-pass-for-fp-int-conversion-of-large-bitint/65528,
this implementation is very similar to ExpandLargeDivRem, which expands
‘fptoui .. to’, ‘fptosi .. to’, ‘uitofp .. to’, ‘sitofp .. to’ instructions
with a bitwidth above a threshold into auto-generated functions. This is
useful for targets like x86_64 that cannot lower fp convertions with more
than 128 bits. The expanded nodes are referring from the IR generated by
`compiler-rt/lib/builtins/floattidf.c`, `compiler-rt/lib/builtins/fixdfti.c`,
and etc.
Corner cases:
1. For fp16: as there is no related builtins added in compliler-rt. So I
mainly utilized the fp32 <-> fp16 lib calls to implement.
2. For fp80: as this pass is soft fp emulation and no fp80 instructions can
help in this problem. I recommend users to deprecate this usage. For now, the
implementation uses fp128 as the temporary conversion type and inserts
fptrunc/ext at top/end of the function.
3. For bf16: as clang FE currently doesn't support bf16 algorithm operations
(convert to int, float, +, -, *, ...), this patch doesn't consider bf16 for
now.
4. For unsigned FPToI: since both default hardware behaviors and libgcc are
ignoring "returns 0 for negative input" spec. This pass follows this old way
to ignore unsigned FPToI. See this example:
https://gcc.godbolt.org/z/bnv3jqW1M
The end-to-end tests are uploaded at https://reviews.llvm.org/D138261
Reviewed By: LuoYuanke, mgehre-amd
Differential Revision: https://reviews.llvm.org/D137241
Currently per-function metadata consists of:
(start-pc, size, features)
This adds a new UAR feature and if it's set an additional element:
(start-pc, size, features, stack-args-size)
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D136078