Summary:
Second patch in series to support Safe Whole Program Devirtualization
Enablement, see RFC here:
http://lists.llvm.org/pipermail/llvm-dev/2019-December/137543.html
Summarize vcall_visibility metadata in ThinLTO global variable summary.
Depends on D71907.
Reviewers: pcc, evgeny777, steven_wu
Subscribers: mehdi_amini, Prazek, inglorion, hiraditya, dexonsmith, arphaman, ostannard, llvm-commits, cfe-commits, davidxl
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D71911
Since register classes go up to 1024, 32 elements, all masks bits are
needed and a 32-bit shift by 32 is illegal. We didn't have any
instructions theoretically using a 32 element VGPR before
d1dbb5e471
Summary:
I initially encountered those assertions when trying to create
this IR `alignment` attribute from clang's `__attribute__((assume_aligned(imm)))`,
because until D72994 there is no sanity checking for the value of `imm`.
But even then, we have `llvm::Value::MaximumAlignment` constant (which is `536870912`),
which is enforced for clang attributes, and then there are some other magical constant
(`0x40000000` i.e. `1073741824` i.e. `2 * 536870912`) in
`Attribute::getWithAlignment()`/`AttrBuilder::addAlignmentAttr()`.
I strongly suspect that `0x40000000` is incorrect,
and that also should be `llvm::Value::MaximumAlignment`.
Reviewers: erichkeane, hfinkel, jdoerfert, gchatelet, courbet
Reviewed By: erichkeane
Subscribers: hiraditya, cfe-commits, llvm-commits
Tags: #llvm, #clang
Differential Revision: https://reviews.llvm.org/D72998
Summary:
First patch to support Safe Whole Program Devirtualization Enablement,
see RFC here: http://lists.llvm.org/pipermail/llvm-dev/2019-December/137543.html
Always emit !vcall_visibility metadata under -fwhole-program-vtables,
and not just for -fvirtual-function-elimination. The vcall visibility
metadata will (in a subsequent patch) be used to communicate to WPD
which vtables are safe to devirtualize, and we will optionally convert
the metadata to hidden visibility at link time. Subsequent follow on
patches will help enable this by adding vcall_visibility metadata to the
ThinLTO summaries, and always emit type test intrinsics under
-fwhole-program-vtables (and not just for vtables with hidden
visibility).
In order to do this safely with VFE, since for VFE all vtable loads must
be type checked loads which will no longer be the case, this patch adds
a new "Virtual Function Elim" module flag to communicate to GlobalDCE
whether to perform VFE using the vcall_visibility metadata.
One additional advantage of using the vcall_visibility metadata to drive
more WPD at LTO link time is that we can use the same mechanism to
enable more aggressive VFE at LTO link time as well. The link time
option proposed in the RFC will convert vcall_visibility metadata to
hidden (aka linkage unit visibility), which combined with
-fvirtual-function-elimination will allow it to be done more
aggressively at LTO link time under the same conditions.
Reviewers: pcc, ostannard, evgeny777, steven_wu
Subscribers: mehdi_amini, Prazek, hiraditya, dexonsmith, davidxl, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D71907
Calling `operator*` on a WeakVH with a null value yields a null
reference, which is UB. Avoid this by implicitly converting the WeakVH
to a `Value *` rather than dereferencing and then taking the address
for the type conversion.
Differential Revision: https://reviews.llvm.org/D73280
The other 3-op patterns should also be theoretically handled, but
currently there's a bug in the inferred pattern complexity.
I'm not sure what the error handling strategy should be for potential
constant bus violations. I think the correct strategy is to never
produce mixed SGPR and VGPR operands in a typical VOP instruction,
which will trivially avoid them. However, it's possible to still have
hand written MIR (or erroneously transformed code) with these
operands. When these fold, the restriction will be violated. We
currently don't have any verifiers for reg bank legality. For now,
just ignore the restriction.
It might be worth triggering a DAG fallback on verifier error.
Summary:
The primary goal of this refactoring is to separate DWARF optimizing part.
So that it could be reused by linker or by any other client.
There was a thread on llvm-dev discussing the necessity of such a refactoring:
http://lists.llvm.org/pipermail/llvm-dev/2019-September/135068.html.
This is a final part from series of patches for dsymutil.
Previous patches : D71068, D71839, D72476. This patch:
1. Creates lib/DWARFLinker interface :
void addObjectFile(DwarfLinkerObjFile &ObjFile);
bool link();
void setOptions;
1. Moves all linking logic from tools/dsymutil/DwarfLinkerForBinary
into lib/DWARFLinker.
2. Renames RelocationManager into AddressesManager.
3. Remarks creation logic moved from separate parallel execution
into object file loading routine.
Testing: it passes "check-all" lit testing. MD5 checksum for clang .dSYM bundle
matches for the dsymutil with/without that patch.
Reviewers: JDevlieghere, friss, dblaikie, aprantl, jdoerfert
Reviewed By: JDevlieghere
Subscribers: merge_guards_bot, hiraditya, jfb, llvm-commits, probinson, thegameg
Tags: #llvm, #debug-info
Differential Revision: https://reviews.llvm.org/D72915
This changes the generated (Instr|Asm|Reg|Regclass)Name tables from this
form:
extern const char HexagonInstrNameData[] = {
/* 0 */ 'G', '_', 'F', 'L', 'O', 'G', '1', '0', 0,
/* 9 */ 'E', 'N', 'D', 'L', 'O', 'O', 'P', '0', 0,
/* 18 */ 'V', '6', '_', 'v', 'd', 'd', '0', 0,
/* 26 */ 'P', 'S', '_', 'v', 'd', 'd', '0', 0,
[...]
};
...to this:
extern const char HexagonInstrNameData[] = {
/* 0 */ "G_FLOG10\0"
/* 9 */ "ENDLOOP0\0"
/* 18 */ "V6_vdd0\0"
/* 26 */ "PS_vdd0\0"
[...]
};
This should make debugging and exploration a lot easier for mortals,
while providing a significant compile-time reduction for common compilers.
To avoid issues with low implementation limits, this is disabled by
default for visual studio or when cross-compiling.
To force output one way or the other, pass
`--long-string-literals=<bool>` to `tablegen`
Reviewers: mstorsjo, rnk
Subscribers: llvm-commit
Differential Revision: https://reviews.llvm.org/D73044
Match the approach in SimplifyDemandedBits where we calculate the demanded elts and then have a common path for the ComputeKnownBits/ComputeNumSignBits call.
In case of loops with multiple exit where all-but-one exit are deoptimizing
it might happen that the first rotation will end up with latch having a deoptimizing
exit. This makes the loop unsuitable for trip-count analysis (say, getLoopEstimatedTripCount)
as well as for loop transformations that know how to handle multple deoptimizing exits.
It pretty much means that canonical form in multple-deoptimizing-exits case should be
with non-deoptimizing exit at latch.
Teach loop-rotation to reach this canonical form by repeating rotation.
-loop-rotate-multi option introduced to control this behavior, currently disabled by default.
Reviewers: skatkov, asbirlea, reames, fhahn
Reviewed By: skatkov
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D73058
Summary:
Immediate vmvnq is code-generated as a simple vector constant in IR,
and left to the backend to recognize that it can be created with an
MVE VMVN instruction. The predicated version is represented as a
select between the input and the same constant, and I've added a
Tablegen isel rule to turn that into a predicated VMVN. (That should
be better than the previous VMVN + VPSEL: it's the same number of
instructions but now it can fold into an adjacent VPT block.)
The unpredicated forms of VBIC and VORR are done by enabling the same
isel lowering as for NEON, recognizing appropriate immediates and
rewriting them as ARMISD::VBICIMM / ARMISD::VORRIMM SDNodes, which I
then instruction-select into the right MVE instructions (now that I've
also reworked those instructions to use the same MC operand encoding).
In order to do that, I had to promote the Tablegen SDNode instance
`NEONvorrImm` to a general `ARMvorrImm` available in MVE as well, and
similarly for `NEONvbicImm`.
The predicated forms of VBIC and VORR are represented as a vector
select between the original input vector and the output of the
unpredicated operation. The main convenience of this is that it still
lets me use the existing isel lowering for VBICIMM/VORRIMM, and not
have to write another copy of the operand encoding translation code.
This intrinsic family is the first to use the `imm_simd` system I put
into the MveEmitter tablegen backend. So, naturally, it showed up a
bug or two (emitting bogus range checks and the like). Fixed those,
and added a full set of tests for the permissible immediates in the
existing Sema test.
Also adjusted the isel pattern for `vmovlb.u8`, which stopped matching
because lowering started turning its input into a VBICIMM. Now it
recognizes the VBICIMM instead.
Reviewers: dmgreen, MarkMurrayARM, miyuki, ostannard
Reviewed By: dmgreen
Subscribers: kristof.beyls, hiraditya, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D72934
Summary:
In NEON, the immediate forms of VBIC and VORR are each represented as
a single MC instruction, which takes its immediate operand already
encoded in a NEON-friendly format: 8 data bits, plus some control bits
indicating how to expand them into a full vector.
In MVE, we represented immediate VBIC and VORR as four separate MC
instructions each, for an 8-bit immediate shifted left by 0, 8, 16 or
24 bits. For each one, the value of the immediate operand is in the
'natural' form, i.e. the numerical value that would actually be BICed
or ORRed into each vector lane (and also the same value shown in
assembly). For example, MVE_VBICIZ16v4i32 takes an operand such as
0xab0000, which NEON would represent as 0xab | (control bits << 8).
The MVE approach is superficially nice (it makes assembly input and
output easy, and it's also nice if you're manually constructing
immediate VBICs). But it turns out that it's better for isel if we
make the NEON and MVE instructions work the same, because the
ARMISD::VBICIMM and VORRIMM node types already encode their immediate
into the NEON format, so it's easier if we can just use it.
Also, this commit reduces the total amount of code rather than
increasing it, which is surely an indication that it really is simpler
to do it this way!
Reviewers: dmgreen, ostannard, miyuki, MarkMurrayARM
Reviewed By: dmgreen
Subscribers: kristof.beyls, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D73205
Since some instruction types aren't allowed as the main instruction also
don't allow them for aliasing instructions.
Differential Revision: https://reviews.llvm.org/D73220
Summary:
This commit adds error checking beyond UndefVarError and fix a number of
Error/Expected related idioms:
- use (EXPECT|ASSERT)_THAT_(ERROR|EXPECTED) instead of errorToBool or
boolean operator
- ASSERT when a further check require the check to be successful to give
a correct result
Reviewers: jhenderson, jdenny, probinson, grimar, arichardson, rnk
Reviewed By: jhenderson
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D72914
Match the approach in SimplifyDemandedBits/ComputeNumSignBits where we calculate the demanded elts and then have a common path for the ComputeKnownBits call.
Match the approach in SimplifyDemandedBits where we calculate the demanded elts and then have a common path for the ComputeKnownBits/ComputeNumSignBits call, additionally we only ever need original demanded elts of the base vector even if the index is unknown.
The low_pc is analog to the DW_AT_call_return_pc, since it describes
the return address after the call. The DW_AT_call_pc is the address
of the call instruction, and we don't use it at the moment.
Differential Revision: https://reviews.llvm.org/D73173
Summary:
... instead of crashing.
On typical exmaple is when there are no available registers.
Reviewers: gchatelet
Subscribers: tschuett, mstojanovic, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D73196
We have a `-dyn-symbols` option. It has a `--dyn-syms` alias
that is not tested in llvm-readobj tests currently.
There was a Object/readobj-elf-versioning.test where it is used,
but I've removed it in D73163. And also it is not the
right place to test it anyways.
Differential revision: https://reviews.llvm.org/D73164
`readobj-elf-versioning.test` was added in rL152436 and
checks how llvm-readobj --dyn-syms prints versioned symbols.
We test the same in `llvm-readobj\ELF\dyn-symbols.test` currently.
This patch removes the test and 4 more support files from Inputs.
Differential revision: https://reviews.llvm.org/D73163
Teresa Johnson