For x86_64, since we don't clobber %rsi (2nd argument) anymore, we don't
have to save/restore it.

Reviewed By: dvyukov

Differential Revision: https://reviews.llvm.org/D63946

llvm-svn: 365229

llvm-svn: 365228

llvm-svn: 365227

Change the interface to return an expected, instead of taking a Status
pointer.

Differential revision: https://reviews.llvm.org/D64163

llvm-svn: 365226

[X86] Update SSE1 MOVLPSrm and MOVHPSrm isel patterns to ensure loads are non-volatile before folding.

These patterns use 128-bit loads, but the instructions only load
64-bits. We shouldn't narrow the load if its volatile.

Fixes another variant of PR42079

llvm-svn: 365225

This was identical to a pattern for MOVPQI2QImr with a bitcast
as an input. But we should be able to turn MOVPQI2QImr into
MOVLPSmr in the execution domain fixup pass so we shouldn't
need this.

llvm-svn: 365224

llvm-svn: 365223

Summary:
Otherwise, when libcxxabi is not an enabled project in the monorepo, we
get a link error because we try to link against non-existent cxxabi_shared.

More generally, we shouldn't change the behavior of the build based on
implicit things like whether a file happens to be at a specific path or
not.

Reviewers: EricWF

Subscribers: mgorny, christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D63883

llvm-svn: 365222

--section-data, --section-relocations and --section-symbols have no
effect for GNU style ouput. This patch changes the docs to point this
out, as it has caught me out on a couple of occasions.

See also https://bugs.llvm.org/show_bug.cgi?id=42522.

llvm-svn: 365221

Summary:
This patch changes expression support to use one instance of
FileCheckNumericVariable per numeric variable rather than one per
variable and per definition. The current system was only necessary for
the last patch of the numeric expression support patch series in order
to handle a line using a variable defined earlier on the same line from
the input text. However this can be dealt more efficiently.

Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar, arichardson, rnk

Subscribers: JonChesterfield, rogfer01, hfinkel, kristina, rnk, tra, arichardson, grimar, dblaikie, probinson, llvm-commits, hiraditya

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64229

llvm-svn: 365220

Summary:
Diagnosing use of undefined variables takes place in
parseNumericVariableUse() and printSubstitutions() for numeric variables
but only takes place in printSubstitutions() for string variables. The
reason for the split location of diagnostics is that parsing is not
aware of the clearing of variables due to --enable-var-scope and thus
use of variables cleared in this way can only be catched by
printSubstitutions().

Beyond the code level inconsistency, there is also a user facing
inconsistency since diagnostics look different between the two
functions. While the diagnostic in printSubstitutions is more verbose,
doing the diagnostic there allows to diagnose all undefined variables
rather than just the first one and error out.

This patch create dummy variable definition when encountering a use of
undefined variable so that parsing can proceed and be diagnosed by
printSubstitutions() later. Tests that were testing whether parsing
fails in such case are thus modified accordingly.

Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar, arichardson, rnk

Subscribers: JonChesterfield, rogfer01, hfinkel, kristina, rnk, tra, arichardson, grimar, dblaikie, probinson, llvm-commits, hiraditya

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64228

llvm-svn: 365219

llvm-svn: 365218

Patch by Christudasan Devadasan.

Differential Revision: https://reviews.llvm.org/D63886

llvm-svn: 365217

When looking for uses/defs to add kill flags, the iterator was double
incremented, skipping the first instruction in the bundle. The use
register in the first bundle instruction was then incorrectly killed.
The "First" instruction should be the BUNDLE itself as the proper
reverse iterator endpoint.

llvm-svn: 365216

llvm-svn: 365215

This add simple Q register forms of bitwise not instructions.

Differential Revision: https://reviews.llvm.org/D63983

llvm-svn: 365214

llvm-svn: 365213

llvm-svn: 365212

Summary:
This allows the DPP combiner to kick in more often. For example the
exclusive scan generated by the atomic optimizer for a divergent atomic
add used to look like this:

        v_mov_b32_e32 v3, v1
        v_mov_b32_e32 v5, v1
        v_mov_b32_e32 v6, v1
        v_mov_b32_dpp v3, v2  wave_shr:1 row_mask:0xf bank_mask:0xf
        s_nop 1
        v_add_u32_dpp v4, v3, v3  row_shr:1 row_mask:0xf bank_mask:0xf bound_ctrl:0
        v_mov_b32_dpp v5, v3  row_shr:2 row_mask:0xf bank_mask:0xf
        v_mov_b32_dpp v6, v3  row_shr:3 row_mask:0xf bank_mask:0xf
        v_add3_u32 v3, v4, v5, v6
        v_mov_b32_e32 v4, v1
        s_nop 1
        v_mov_b32_dpp v4, v3  row_shr:4 row_mask:0xf bank_mask:0xe
        v_add_u32_e32 v3, v3, v4
        v_mov_b32_e32 v4, v1
        s_nop 1
        v_mov_b32_dpp v4, v3  row_shr:8 row_mask:0xf bank_mask:0xc
        v_add_u32_e32 v3, v3, v4
        v_mov_b32_e32 v4, v1
        s_nop 1
        v_mov_b32_dpp v4, v3  row_bcast:15 row_mask:0xa bank_mask:0xf
        v_add_u32_e32 v3, v3, v4
        s_nop 1
        v_mov_b32_dpp v1, v3  row_bcast:31 row_mask:0xc bank_mask:0xf
        v_add_u32_e32 v1, v3, v1
        v_add_u32_e32 v1, v2, v1
        v_readlane_b32 s0, v1, 63

But now most of the dpp movs are combined into adds:

        v_mov_b32_e32 v3, v1
        v_mov_b32_e32 v5, v1
        s_nop 0
        v_mov_b32_dpp v3, v2  wave_shr:1 row_mask:0xf bank_mask:0xf
        s_nop 1
        v_add_u32_dpp v4, v3, v3  row_shr:1 row_mask:0xf bank_mask:0xf bound_ctrl:0
        v_mov_b32_dpp v5, v3  row_shr:2 row_mask:0xf bank_mask:0xf
        v_mov_b32_dpp v1, v3  row_shr:3 row_mask:0xf bank_mask:0xf
        v_add3_u32 v1, v4, v5, v1
        s_nop 1
        v_add_u32_dpp v1, v1, v1  row_shr:4 row_mask:0xf bank_mask:0xe
        s_nop 1
        v_add_u32_dpp v1, v1, v1  row_shr:8 row_mask:0xf bank_mask:0xc
        s_nop 1
        v_add_u32_dpp v1, v1, v1  row_bcast:15 row_mask:0xa bank_mask:0xf
        s_nop 1
        v_add_u32_dpp v1, v1, v1  row_bcast:31 row_mask:0xc bank_mask:0xf
        v_add_u32_e32 v1, v2, v1
        v_readlane_b32 s0, v1, 63

Reviewers: arsenm, vpykhtin

Subscribers: kzhuravl, nemanjai, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kbarton, MaskRay, jfb, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64207

llvm-svn: 365211

This case implicitly falls-through, which is fine now as it's at the end of the
function, but it seems like an accident waiting to happen.

llvm-svn: 365210

llvm-svn: 365209

Differential Revision: https://reviews.llvm.org/D63642

llvm-svn: 365208

This patch is a major part of my GSoC project, aimed to improve the bug
reports of the analyzer.

TL;DR: Help the analyzer understand that some conditions are important,
and should be explained better. If an CFGBlock is a control dependency
of a block where an expression value is tracked, explain the condition
expression better by tracking it.

if (A) // let's explain why we believe A to be true
  10 / x; // division by zero

This is an experimental feature, and can be enabled by the
off-by-default analyzer configuration "track-conditions".

In detail:

This idea was inspired by the program slicing algorithm. Essentially,
two things are used to produce a program slice (a subset of the program
relevant to a (statement, variable) pair): data and control
dependencies. The bug path (the linear path in the ExplodedGraph that leads
from the beginning of the analysis to the error node) enables to
analyzer to argue about data dependencies with relative ease.

Control dependencies are a different slice of the cake entirely.

Just because we reached a branch during symbolic execution, it
doesn't mean that that particular branch has any effect on whether the
bug would've occured. This means that we can't simply rely on the bug
path to gather control dependencies.

In previous patches, LLVM's IDFCalculator, which works on a control flow
graph rather than the ExplodedGraph was generalized to solve this issue.
We use this information to heuristically guess that the value of a tracked
expression depends greatly on it's control dependencies, and start
tracking them as well.

After plenty of evaluations this was seen as great idea, but still
lacking refinements (we should have different descriptions about a
conditions value), hence it's off-by-default.

Differential Revision: https://reviews.llvm.org/D62883

llvm-svn: 365207

llvm-svn: 365206

Summary: Added highlighting for variable references using VisitDeclRefExpr.

Reviewers: hokein, sammccall

Subscribers: ilya-biryukov, MaskRay, jkorous, arphaman, kadircet, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64199

llvm-svn: 365205

Summary:
Clang-tidy checks may emit duplicated messages (clang-tidy tool
deduplicate them in its custom diagnostic consumer), and we may show
multiple duplicated diagnostics in the UI, which is really bad.

This patch makes clangd do the deduplication, and revert the change
rL363889.

Reviewers: sammccall

Subscribers: ilya-biryukov, MaskRay, jkorous, mgrang, arphaman, kadircet, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64127

llvm-svn: 365204

Reintroduces the scalable vector IR type from D32530, after it was reverted
a couple of times due to increasing chromium LTO build times. This latest
incarnation removes the walk over aggregate types from the verifier entirely,
in favor of rejecting scalable vectors in the isValidElementType methods in
ArrayType and StructType. This removes the 70% degradation observed with
the second repro tarball from PR42210.

Reviewers: thakis, hans, rengolin, sdesmalen

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D64079

llvm-svn: 365203

Revision r365061 changed a skip of debug instructions for a skip
of meta instructions. This is not safe, as IMPLICIT_DEF is classed
as a meta instruction.

llvm-svn: 365202

On RISC-V, the `cycle` CSR holds a 64-bit count of the number of clock
cycles executed by the core, from an arbitrary point in the past. This
matches the intended semantics of `@llvm.readcyclecounter()`, which we
currently leave to the default lowering (to the constant 0).

With this patch, we will now correctly lower this intrinsic to the
intended semantics, using the user-space instruction `rdcycle`. On
64-bit targets, we can directly lower to this instruction.

On 32-bit targets, we need to do more, as `rdcycle` only returns the low
32-bits of the `cycle` CSR. In this case, we perform a custom lowering,
based on the PowerPC lowering, using `rdcycleh` to obtain the high
32-bits of the `cycle` CSR. This custom lowering inserts a new basic
block which detects overflow in the high 32-bits of the `cycle` CSR
during reading (because multiple instructions are required to read). The
emitted assembly matches the suggested assembly in the RISC-V
specification.

Differential Revision: https://reviews.llvm.org/D64125

llvm-svn: 365201

Since OPT_UNKNOWN args never have any values and consist only of
spelling (and are never aliased), this doesn't make any difference in
practice, but it's more consistent with Arg's guidance to use
getAsString() for diagnostics, and it matches what clang does.

Also tweak two tests to use an unknown option that contains '=' for
additional coverage while here. (The new tests pass fine with the old
code too though.)

llvm-svn: 365200

should not have been added.

llvm-svn: 365199

Revision r365061 changed a skip of debug instructions for a skip
of meta instructions. This is not safe, as IMPLICIT_DEF is classed
as a meta instruction.

llvm-svn: 365198

I intend to improve the analyzer's bug reports by tracking condition
expressions.

01 bool b = messyComputation();
02 int i = 0;
03 if (b) // control dependency of the bug site, let's explain why we assume val
04        // to be true
05   10 / i; // warn: division by zero

I'll detail this heuristic in the followup patch, strictly related to this one
however:

* Create the new ControlDependencyCalculator class that uses llvm::IDFCalculator
  to (lazily) calculate control dependencies for Clang's CFG.
* A new debug checker debug.DumpControlDependencies is added for lit tests
* Add unittests

Differential Revision: https://reviews.llvm.org/D62619

llvm-svn: 365197

Reviewers: asb, lenary

Reviewed By: asb, lenary

Subscribers: MaskRay, hiraditya, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, psnobl, benna, Jim, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64139

Patch by James Clarke (jrtc27)

llvm-svn: 365195

llvm-svn: 365194

Differential revision: https://reviews.llvm.org/D61672

llvm-svn: 365193

Summary:
Comment explaining the interaction between parsing of numeric variable
definition and uses in parseNumericVariableUse is stale since it
suggests both use and definition parsing is done in the same function.
This was the case in a previous version of the patch committed as
71d3f227 but is no longer the case. This
patch updates the comment accordingly.

Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar, arichardson, rnk

Subscribers: JonChesterfield, rogfer01, hfinkel, kristina, rnk, tra, arichardson, grimar, dblaikie, probinson, llvm-commits, hiraditya

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64227

llvm-svn: 365192

Summary:
Both callers of parseNumericVariableDefinition() perform the same extra
check that no character is found after the variable name. This patch
factors out this check into parseNumericVariableDefinition().

Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar, arichardson, rnk

Subscribers: JonChesterfield, rogfer01, hfinkel, kristina, rnk, tra, arichardson, grimar, dblaikie, probinson, llvm-commits, hiraditya

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64226

llvm-svn: 365191

llvm-svn: 365190

llvm-svn: 365189