Commit Graph

678 Commits

Author SHA1 Message Date
Johannes Doerfert b1c788d051 [Attributor][FIX] Prevent alignment breakage wrt. must-tail calls
If we have a must-tail call the callee and caller need to have matching
ABIs. Part of that is alignment which we might modify when we deduce
alignment of arguments of either. Since we would need to keep them in
sync, which is not as simple, we simply avoid deducing alignment for
arguments of the must-tail caller or callee.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D76673
2020-04-01 21:40:07 -05:00
Florian Hahn 862766e01e [Verifier] Verify matrix dimensions operands match vector size.
This patch adds checks to the verifier to ensure the dimension arguments
passed to the matrix intrinsics match the vector types for their
arugments/return values.

Reviewers: anemet, Gerolf, andrew.w.kaylor, LuoYuanke

Reviewed By: anemet

Differential Revision: https://reviews.llvm.org/D77129
2020-04-01 09:21:39 +01:00
Eli Friedman 1ee6ec2bf3 Remove "mask" operand from shufflevector.
Instead, represent the mask as out-of-line data in the instruction. This
should be more efficient in the places that currently use
getShuffleVector(), and paves the way for further changes to add new
shuffles for scalable vectors.

This doesn't change the syntax in textual IR. And I don't currently plan
to change the bitcode encoding in this patch, although we'll probably
need to do something once we extend shufflevector for scalable types.

I expect that once this is finished, we can then replace the raw "mask"
with something more appropriate for scalable vectors.  Not sure exactly
what this looks like at the moment, but there are a few different ways
we could handle it.  Maybe we could try to describe specific shuffles.
Or maybe we could define it in terms of a function to convert a fixed-length
array into an appropriate scalable vector, using a "step", or something
like that.

Differential Revision: https://reviews.llvm.org/D72467
2020-03-31 13:08:59 -07:00
John McCall 9514c048d8 Use optimal layout and preserve alloca alignment in coroutine frames.
Previously, we would ignore alloca alignment when building the frame
and just use the natural alignment of the allocated type.  If an alloca
is over-aligned for its IR type, this could lead to a frame entry with
inadequate alignment for the downstream uses of the alloca.

Since highly-aligned fields also tend to produce poor layouts under a
naive layout algorithm, I've also switched coroutine frames to use the
new optimal struct layout algorithm.

In order to communicate the frame size and alignment to later passes,
I needed to set align+dereferenceable attributes on the frame-pointer
parameter of the resume function.  This is clearly the right thing to
do, but the align attribute currently seems to result in assumptions
being added during inlining that the optimizer cannot easily remove.
2020-03-26 00:51:09 -04:00
Matt Arsenault b76bbcc60d Verifier: Check bswap is supported size
Make sure it is a multiple of 2 bytes as specified in the LangRef.
2020-03-22 12:15:25 -04:00
Simon Pilgrim 34b8a0d599 [Verifier] Silence static analyzer null dereference warning (PR45118)
As discussed on PR45118, getInlinedAtScope() shouldn't ever return null. So we can simplify the logic to an assertion and remove all other null tests.
2020-03-17 16:01:23 +00:00
Serguei Katkov ad643d5e93 [Verifier] Remove invalid verifier check
According to LangRef for unordered atomic memory transfer intrinsics
"The first three arguments are the same as they are in the @llvm.memcpy intrinsic, with the added constraint that
 len is required to be a positive integer multiple of the element_size. If len is not a positive integer multiple
 of element_size, then the behaviour of the intrinsic is undefined."

So the len is not multiple of element size is just an undefined behavior and verifier should not complain about that
as undefined behavior is allowed in LLVM IR.

This change removes the verifier check for this condition

Reviewers: reames
Reviewed By: reames
Subscribers: dantrushin, hiraditya, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D76116
2020-03-16 12:00:08 +07:00
Arlo Siemsen 1478ed69d3 Add support for SHA256 source file checksums in debug info
LLVM currently supports CSK_MD5 and CSK_SHA1 source file checksums in
debug info. This change adds support for CSK_SHA256 checksums.

The SHA256 checksums are supported by the CodeView debug format.

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D75785
2020-03-12 16:32:05 -07:00
Tyker f16f139db4 Basis of dropping uses in llvm.assume.
Summary: This patch adds the basic utilities to deal with dropable uses. dropable uses are uses that we rather drop than prevent transformations, for now they are limited to uses in llvm.assume.

Reviewers: jdoerfert, sstefan1

Reviewed By: jdoerfert

Subscribers: uenoku, lebedev.ri, mgorny, hiraditya, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73404
2020-03-12 10:10:22 +01:00
Tyker 70c0a9675d [AssumeBundles] Enforce constraints on the operand bundle of llvm.assume
Summary: Add verification that operand bundles on an llvm.assume are well formed to the verify pass.

Reviewers: jdoerfert

Reviewed By: jdoerfert

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75269
2020-03-11 23:53:48 +01:00
Adrian Prantl 5c83bedeca More principled implementation of DISubprogram::describes()
Previously we would also accept DISubprograms that matched in name
only, but this doesn't appear to be necessary any more.

I did a Full and Thin LTO build of Clang and it completed without a warning.

Differential Revision: https://reviews.llvm.org/D75213
2020-03-02 10:03:14 -08:00
Adrian Prantl a5a07b8041 Visit previously unreachable nodes in the debug info metadata verifier.
This allows for diagnosing malformed LLVM IR debug info metadata such
as the one in the testcase.

<rdar://problem/59756060>

Differential Revision: https://reviews.llvm.org/D75212
2020-02-26 14:48:08 -08:00
Bill Wendling 23c2a5ce33 Allow "callbr" to return non-void values
Summary:
Terminators in LLVM aren't prohibited from returning values. This means that
the "callbr" instruction, which is used for "asm goto", can support "asm goto
with outputs."

This patch removes all restrictions against "callbr" returning values. The
heavy lifting is done by the code generator. The "INLINEASM_BR" instruction's
a terminator, and the code generator doesn't allow non-terminator instructions
after a terminator. In order to correctly model the feature, we need to copy
outputs from "INLINEASM_BR" into virtual registers. Of course, those copies
aren't terminators.

To get around this issue, we split the block containing the "INLINEASM_BR"
right before the "COPY" instructions. This results in two cheats:

  - Any physical registers defined by "INLINEASM_BR" need to be marked as
    live-in into the block with the "COPY" instructions. This violates an
    assumption that physical registers aren't marked as "live-in" until after
    register allocation. But it seems as if the live-in information only
    needs to be correct after register allocation. So we're able to get away
    with this.

  - The indirect branches from the "INLINEASM_BR" are moved to the "COPY"
    block. This is to satisfy PHI nodes.

I've been told that MLIR can support this handily, but until we're able to
use it, we'll have to stick with the above.

Reviewers: jyknight, nickdesaulniers, hfinkel, MaskRay, lattner

Reviewed By: nickdesaulniers, MaskRay, lattner

Subscribers: rriddle, qcolombet, jdoerfert, MatzeB, echristo, MaskRay, xbolva00, aaron.ballman, cfe-commits, JonChesterfield, hiraditya, llvm-commits, rnk, craig.topper

Tags: #llvm, #clang

Differential Revision: https://reviews.llvm.org/D69868
2020-02-24 18:29:06 -08:00
Bevin Hansson 6e561d1c94 [Intrinsic] Add fixed point saturating division intrinsics.
Summary:
This patch adds intrinsics and ISelDAG nodes for signed
and unsigned fixed-point division:

```
llvm.sdiv.fix.sat.*
llvm.udiv.fix.sat.*
```

These intrinsics perform scaled, saturating division
on two integers or vectors of integers. They are
required for the implementation of the Embedded-C
fixed-point arithmetic in Clang.

Reviewers: bjope, leonardchan, craig.topper

Subscribers: hiraditya, jdoerfert, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71550
2020-02-24 10:50:52 +01:00
Jim Lin 466f8843f5 [NFC] Remove trailing space
sed -Ei 's/[[:space:]]+$//' include/**/*.{def,h,td} lib/**/*.{cpp,h,td}
2020-02-18 10:49:13 +08:00
Fangrui Song a35b7288b1 [IR] Change maybeSetDSOLocal to isImplicitDSOLocal
This allows some simplification.
2020-02-16 13:14:15 -08:00
Tyker 15f54d348b [NFC] Factor out function to detect if an attribute has an argument. 2020-02-03 22:27:24 +01:00
Tyker d431c5d9af Revert "[NFC] Factor out function to detect if an attribute has an argument."
This reverts commit ff1b9add2f.
2020-02-02 15:03:06 +01:00
Tyker ff1b9add2f [NFC] Factor out function to detect if an attribute has an argument.
Reviewers: jdoerfert

Reviewed By: jdoerfert

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D72884
2020-02-02 14:50:31 +01:00
serge-sans-paille fd09f12f32 Implement -fsemantic-interposition
First attempt at implementing -fsemantic-interposition.

Rely on GlobalValue::isInterposable that already captures most of the expected
behavior.

Rely on a ModuleFlag to state whether we should respect SemanticInterposition or
not. The default remains no.

So this should be a no-op if -fsemantic-interposition isn't used, and if it is,
isInterposable being already used in most optimisation, they should honor it
properly.

Note that it only impacts architecture compiled with -fPIC and no pie.

Differential Revision: https://reviews.llvm.org/D72829
2020-01-31 14:02:33 +01:00
Guillaume Chatelet 879c825cb8 [instrinsics] Add @llvm.memcpy.inline instrinsics
Summary:
This is a follow up on D61634. It adds an LLVM IR intrinsic to allow better implementation of memcpy from C++.
A follow up CL will add the intrinsics in Clang.

Reviewers: courbet, theraven, t.p.northover, jdoerfert, tejohnson

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71710
2020-01-28 09:42:01 +01:00
Wang, Pengfei 17b8f96d65 [FPEnv] Divide macro INSTRUCTION into INSTRUCTION and DAG_INSTRUCTION,
and macro FUNCTION likewise. NFCI.

Some functions like fmuladd don't really have a node, we should divide
the declaration form those have node to avoid introducing fake nodes.

Differential Revision: https://reviews.llvm.org/D72871
2020-01-27 10:38:05 +08:00
Guillaume Chatelet cc034a5883 [IR] masked gather/scatter alignment should be set
Summary: masked_load and masked_store instructions require the alignment to be specified and a power of two. It seems to me that this requirement applies to masked_gather and masked_scatter as well.

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73179
2020-01-26 18:51:36 +01:00
Fangrui Song 22467e2595 Add function attribute "patchable-function-prefix" to support -fpatchable-function-entry=N,M where M>0
Similar to the function attribute `prefix` (prefix data),
"patchable-function-prefix" inserts data (M NOPs) before the function
entry label.

-fpatchable-function-entry=2,1 (1 NOP before entry, 1 NOP after entry)
will look like:

```
  .type	foo,@function
.Ltmp0:               # @foo
  nop
foo:
.Lfunc_begin0:
  # optional `bti c` (AArch64 Branch Target Identification) or
  # `endbr64` (Intel Indirect Branch Tracking)
  nop

  .section  __patchable_function_entries,"awo",@progbits,get,unique,0
  .p2align  3
  .quad .Ltmp0
```

-fpatchable-function-entry=N,0 + -mbranch-protection=bti/-fcf-protection=branch has two reasonable
placements (https://gcc.gnu.org/ml/gcc-patches/2020-01/msg01185.html):

```
(a)         (b)

func:       func:
.Ltmp0:     bti c
  bti c     .Ltmp0:
  nop       nop
```

(a) needs no additional code. If the consensus is to go for (b), we will
need more code in AArch64BranchTargets.cpp / X86IndirectBranchTracking.cpp .

Differential Revision: https://reviews.llvm.org/D73070
2020-01-23 17:02:27 -08:00
Fangrui Song 4d1e23e3b3 [AArch64] Add function attribute "patchable-function-entry" to add NOPs at function entry
The Linux kernel uses -fpatchable-function-entry to implement DYNAMIC_FTRACE_WITH_REGS
for arm64 and parisc. GCC 8 implemented
-fpatchable-function-entry, which can be seen as a generalized form of
-mnop-mcount. The N,M form (function entry points before the Mth NOP) is
currently only used by parisc.

This patch adds N,0 support to AArch64 codegen. N is represented as the
function attribute "patchable-function-entry". We will use a different
function attribute for M, if we decide to implement it.

The patch reuses the existing patchable-function pass, and
TargetOpcode::PATCHABLE_FUNCTION_ENTER which is currently used by XRay.

When the integrated assembler is used, __patchable_function_entries will
be created for each text section with the SHF_LINK_ORDER flag to prevent
--gc-sections (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93197) and
COMDAT (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93195) issues.

Retrospectively, __patchable_function_entries should use a PC-relative
relocation type to avoid the SHF_WRITE flag and dynamic relocations.

"patchable-function-entry"'s interaction with Branch Target
Identification is still unclear (see
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92424 for GCC discussions).

Reviewed By: peter.smith

Differential Revision: https://reviews.llvm.org/D72215
2020-01-10 09:55:51 -08:00
Simon Pilgrim 25dd99fab2 Fix "pointer is null" static analyzer warning. NFCI.
Use cast<> instead of dyn_cast<> since we know that the pointer should be valid (and is dereferenced immediately).
2020-01-09 12:37:38 +00:00
Bevin Hansson 8e2b44f7e0 [Intrinsic] Add fixed point division intrinsics.
Summary:
This patch adds intrinsics and ISelDAG nodes for
signed and unsigned fixed-point division:

  llvm.sdiv.fix.*
  llvm.udiv.fix.*

These intrinsics perform scaled division on two
integers or vectors of integers. They are required
for the implementation of the Embedded-C fixed-point
arithmetic in Clang.

Patch by: ebevhan

Reviewers: bjope, leonardchan, efriedma, craig.topper

Reviewed By: craig.topper

Subscribers: Ka-Ka, ilya, hiraditya, jdoerfert, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70007
2020-01-08 15:17:46 +01:00
Bill Wendling e886e762dd Revert "Allow output constraints on "asm goto""
This reverts commit 52366088a8.

I accidentally pushed this before supporting changes.
2020-01-07 13:44:08 -08:00
Bill Wendling 52366088a8 Allow output constraints on "asm goto"
Summary:
Remove the restrictions that preventing "asm goto" from returning non-void
values. The values returned by "asm goto" are only valid on the "fallthrough"
path.

Reviewers: jyknight, nickdesaulniers, hfinkel

Reviewed By: jyknight, nickdesaulniers

Subscribers: rsmith, hiraditya, llvm-commits, cfe-commits, craig.topper, rnk

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D69876
2020-01-07 13:40:26 -08:00
Kevin P. Neal b1d8576b0a This adds constrained intrinsics for the signed and unsigned conversions
of integers to floating point.

This includes some of Craig Topper's changes for promotion support from
D71130.

Differential Revision: https://reviews.llvm.org/D69275
2019-12-17 10:06:51 -05:00
Reid Kleckner 5d986953c8 [IR] Split out target specific intrinsic enums into separate headers
This has two main effects:
- Optimizes debug info size by saving 221.86 MB of obj file size in a
  Windows optimized+debug build of 'all'. This is 3.03% of 7,332.7MB of
  object file size.
- Incremental step towards decoupling target intrinsics.

The enums are still compact, so adding and removing a single
target-specific intrinsic will trigger a rebuild of all of LLVM.
Assigning distinct target id spaces is potential future work.

Part of PR34259

Reviewers: efriedma, echristo, MaskRay

Reviewed By: echristo, MaskRay

Differential Revision: https://reviews.llvm.org/D71320
2019-12-11 18:02:14 -08:00
Matt Arsenault 49d731b5e0 Verifier: Check frame-pointer attribute values
There are a few places that check specific string attributes have
particular values, and assert if they are something else. The verifier
should catch these kinds of cases.
2019-12-11 19:53:49 +05:30
Ulrich Weigand 9db13b5a7d [FPEnv] Constrained FCmp intrinsics
This adds support for constrained floating-point comparison intrinsics.

Specifically, we add:

      declare <ty2>
      @llvm.experimental.constrained.fcmp(<type> <op1>, <type> <op2>,
                                          metadata <condition code>,
                                          metadata <exception behavior>)
      declare <ty2>
      @llvm.experimental.constrained.fcmps(<type> <op1>, <type> <op2>,
                                           metadata <condition code>,
                                           metadata <exception behavior>)

The first variant implements an IEEE "quiet" comparison (i.e. we only
get an invalid FP exception if either argument is a SNaN), while the
second variant implements an IEEE "signaling" comparison (i.e. we get
an invalid FP exception if either argument is any NaN).

The condition code is implemented as a metadata string.  The same set
of predicates as for the fcmp instruction is supported (except for the
"true" and "false" predicates).

These new intrinsics are mapped by SelectionDAG codegen onto two new
ISD opcodes, ISD::STRICT_FSETCC and ISD::STRICT_FSETCCS, again
representing quiet vs. signaling comparison operations.  Otherwise
those nodes look like SETCC nodes, with an additional chain argument
and result as usual for strict FP nodes.  The patch includes support
for the common legalization operations for those nodes.

The patch also includes full SystemZ back-end support for the new
ISD nodes, mapping them to all available SystemZ instruction to
fully implement strict semantics (scalar and vector).

Differential Revision: https://reviews.llvm.org/D69281
2019-12-07 11:28:39 +01:00
Serge Pavlov 0c50c0b055 [FEnv] File with properties of constrained intrinsics
Summary
In several places we need to enumerate all constrained intrinsics or IR
nodes that should be represented by them. It is easy to miss some of
the cases. To make working with these intrinsics more convenient and
robust, this change introduces file containing definitions of all
constrained intrinsics and some of their properties. This file can be
included to generate constrained intrinsics processing code.

Reviewers: kpn, andrew.w.kaylor, cameron.mcinally, uweigand

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69887
2019-11-20 13:30:07 +07:00
Reid Kleckner 05da2fe521 Sink all InitializePasses.h includes
This file lists every pass in LLVM, and is included by Pass.h, which is
very popular. Every time we add, remove, or rename a pass in LLVM, it
caused lots of recompilation.

I found this fact by looking at this table, which is sorted by the
number of times a file was changed over the last 100,000 git commits
multiplied by the number of object files that depend on it in the
current checkout:
  recompiles    touches affected_files  header
  342380        95      3604    llvm/include/llvm/ADT/STLExtras.h
  314730        234     1345    llvm/include/llvm/InitializePasses.h
  307036        118     2602    llvm/include/llvm/ADT/APInt.h
  213049        59      3611    llvm/include/llvm/Support/MathExtras.h
  170422        47      3626    llvm/include/llvm/Support/Compiler.h
  162225        45      3605    llvm/include/llvm/ADT/Optional.h
  158319        63      2513    llvm/include/llvm/ADT/Triple.h
  140322        39      3598    llvm/include/llvm/ADT/StringRef.h
  137647        59      2333    llvm/include/llvm/Support/Error.h
  131619        73      1803    llvm/include/llvm/Support/FileSystem.h

Before this change, touching InitializePasses.h would cause 1345 files
to recompile. After this change, touching it only causes 550 compiles in
an incremental rebuild.

Reviewers: bkramer, asbirlea, bollu, jdoerfert

Differential Revision: https://reviews.llvm.org/D70211
2019-11-13 16:34:37 -08:00
aqjune e87d71668e [IR] Redefine Freeze instruction
Summary:
This patch redefines freeze instruction from being UnaryOperator to a subclass of UnaryInstruction.

ConstantExpr freeze is removed, as discussed in the previous review.
FreezeOperator is not added because there's no ConstantExpr freeze.
`freeze i8* null` test is added to `test/Bindings/llvm-c/freeze.ll` as well, because the null pointer-related bug in `tools/llvm-c/echo.cpp` is now fixed.
InstVisitor has visitFreeze now because freeze is not unaryop anymore.

Reviewers: whitequark, deadalnix, craig.topper, jdoerfert, lebedev.ri

Reviewed By: craig.topper, lebedev.ri

Subscribers: regehr, nlopes, mehdi_amini, hiraditya, steven_wu, dexonsmith, jfb, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69932
2019-11-12 10:49:00 +09:00
aqjune 58acbce3de [IR] Add Freeze instruction
Summary:
- Define Instruction::Freeze, let it be UnaryOperator
- Add support for freeze to LLLexer/LLParser/BitcodeReader/BitcodeWriter
  The format is `%x = freeze <ty> %v`
- Add support for freeze instruction to llvm-c interface.
- Add m_Freeze in PatternMatch.
- Erase freeze when lowering IR to SelDag.

Reviewers: deadalnix, hfinkel, efriedma, lebedev.ri, nlopes, jdoerfert, regehr, filcab, delcypher, whitequark

Reviewed By: lebedev.ri, jdoerfert

Subscribers: jfb, kristof.beyls, hiraditya, lebedev.ri, steven_wu, dexonsmith, xbolva00, delcypher, spatel, regehr, trentxintong, vsk, filcab, nlopes, mehdi_amini, deadalnix, llvm-commits

Differential Revision: https://reviews.llvm.org/D29011
2019-11-05 15:54:56 +09:00
Stefan Stipanovic f35740d6e9 NoFree argument attribute.
Summary: Deducing nofree atrribute for function arguments.

Reviewers: jdoerfert

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67886
2019-11-02 19:40:48 +01:00
Stefan Stipanovic 5fb1782918 Revert "NoFree argument attribute."
This reverts commit c12efa2ed0.
2019-11-02 17:31:02 +01:00
Stefan Stipanovic c12efa2ed0 NoFree argument attribute.
Summary: Deducing nofree atrribute for function arguments.

Reviewers: jdoerfert

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67886
2019-11-02 16:35:38 +01:00
Andrew Paverd d157a9bc8b Add Windows Control Flow Guard checks (/guard:cf).
Summary:
A new function pass (Transforms/CFGuard/CFGuard.cpp) inserts CFGuard checks on
indirect function calls, using either the check mechanism (X86, ARM, AArch64) or
or the dispatch mechanism (X86-64). The check mechanism requires a new calling
convention for the supported targets. The dispatch mechanism adds the target as
an operand bundle, which is processed by SelectionDAG. Another pass
(CodeGen/CFGuardLongjmp.cpp) identifies and emits valid longjmp targets, as
required by /guard:cf. This feature is enabled using the `cfguard` CC1 option.

Reviewers: thakis, rnk, theraven, pcc

Subscribers: ychen, hans, metalcanine, dmajor, tomrittervg, alex, mehdi_amini, mgorny, javed.absar, kristof.beyls, hiraditya, steven_wu, dexonsmith, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D65761
2019-10-28 15:19:39 +00:00
David Stenberg 1ae2d9a2bd [DebugInfo] Add a DW_OP_LLVM_entry_value operation
Summary:
Internally in LLVM's metadata we use DW_OP_entry_value operations with
the same semantics as DWARF; that is, its operand specifies the number
of bytes that the entry value covers.

At the time of emitting entry values we don't know the emitted size of
the DWARF expression that the entry value will cover. Currently the size
is hardcoded to 1 in DIExpression, and other values causes the verifier
to fail. As the size is 1, that effectively means that we can only have
valid entry values for registers that can be encoded in one byte, which
are the registers with DWARF numbers 0 to 31 (as they can be encoded as
single-byte DW_OP_reg0..DW_OP_reg31 rather than a multi-byte
DW_OP_regx). It is a bit confusing, but it seems like llvm-dwarfdump
will print an operation "correctly", even if the byte size is less than
that, which may make it seem that we emit correct DWARF for registers
with DWARF numbers > 31. If you instead use readelf for such cases, it
will interpret the number of specified bytes as a DWARF expression. This
seems like a limitation in llvm-dwarfdump.

As suggested in D66746, a way forward would be to add an internal
variant of DW_OP_entry_value, DW_OP_LLVM_entry_value, whose operand
instead specifies the number of operations that the entry value covers,
and we then translate that into the byte size at the time of emission.

In this patch that internal operation is added. This patch keeps the
limitation that a entry value can only be applied to simple register
locations, but it will fix the issue with the size operand being
incorrect for DWARF numbers > 31.

Reviewers: aprantl, vsk, djtodoro, NikolaPrica

Reviewed By: aprantl

Subscribers: jyknight, fedor.sergeev, hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D67492

llvm-svn: 374881
2019-10-15 11:31:21 +00:00
Kevin P. Neal 1c3d19c82d [FPEnv] Add constrained intrinsics for lrint and lround
Earlier in the year intrinsics for lrint, llrint, lround and llround were
added to llvm. The constrained versions are now implemented here.

Reviewed by:	andrew.w.kaylor, craig.topper, cameron.mcinally
Approved by:	craig.topper
Differential Revision:	https://reviews.llvm.org/D64746

llvm-svn: 373900
2019-10-07 13:20:00 +00:00
Nick Desaulniers 93d87260f1 [Verifier] add invariant check for callbr
Summary:
The list of indirect labels should ALWAYS have their blockaddresses as
argument operands to the callbr (but not necessarily the other way
around).  Add an invariant that checks this.

The verifier catches a bad test case that was added recently in r368478.
I think that was a simple mistake, and the test was made less strict in
regards to the precise addresses (as those weren't specifically the
point of the test).

This invariant will be used to find a reported bug.

Link: https://www.spinics.net/lists/arm-kernel/msg753473.html
Link: https://github.com/ClangBuiltLinux/linux/issues/649

Reviewers: craig.topper, void, chandlerc

Reviewed By: void

Subscribers: ychen, lebedev.ri, javed.absar, kristof.beyls, hiraditya, llvm-commits, srhines

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67196

llvm-svn: 372923
2019-09-25 22:28:27 +00:00
Simon Pilgrim 638933acab Verifier - silence static analyzer dyn_cast<VectorType> null dereference warnings. NFCI.
The static analyzer is warning about potential null dereferences, but we should be able to use cast<VectorType> directly and if not assert will fire for us.

llvm-svn: 372529
2019-09-22 21:01:23 +00:00
Adrian Prantl 0779dffbd4 Remove the obsolete BlockByRefStruct flag from LLVM IR
DIFlagBlockByRefStruct is an unused DIFlag that originally was used by
clang to express (Objective-)C block captures in debug info. For the
last year Clang has been emitting complex DIExpressions to describe
block captures instead, which makes all the code supporting this flag
redundant.

This patch removes the flag and all supporting "dead" code, so we can
reuse the bit for something else in the future.

Since this only affects debug info generated by Clang with the block
extension this mostly affects Apple platforms and I don't have any
bitcode compatibility concerns for removing this. The Verifier will
reject debug info that uses the bit and thus degrade gracefully when
LTO'ing older bitcode with a newer compiler.

rdar://problem/44304813

Differential Revision: https://reviews.llvm.org/D67453

llvm-svn: 372272
2019-09-18 22:38:56 +00:00
Bjorn Pettersson 5e331e4ce8 [Intrinsic] Add the llvm.umul.fix.sat intrinsic
Summary:
Add an intrinsic that takes 2 unsigned integers with
the scale of them provided as the third argument and
performs fixed point multiplication on them. The
result is saturated and clamped between the largest and
smallest representable values of the first 2 operands.

This is a part of implementing fixed point arithmetic
in clang where some of the more complex operations
will be implemented as intrinsics.

Patch by: leonardchan, bjope

Reviewers: RKSimon, craig.topper, bevinh, leonardchan, lebedev.ri, spatel

Reviewed By: leonardchan

Subscribers: ychen, wuzish, nemanjai, MaskRay, jsji, jdoerfert, Ka-Ka, hiraditya, rjmccall, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57836

llvm-svn: 371308
2019-09-07 12:16:14 +00:00
Kevin P. Neal ddf13c00ed [FPEnv] Add fptosi and fptoui constrained intrinsics.
This implements constrained floating point intrinsics for FP to signed and
unsigned integers.

Quoting from D32319:
The purpose of the constrained intrinsics is to force the optimizer to
respect the restrictions that will be necessary to support things like the
STDC FENV_ACCESS ON pragma without interfering with optimizations when
these restrictions are not needed.

Reviewed by:	Andrew Kaylor, Craig Topper, Hal Finkel, Cameron McInally, Roman Lebedev, Kit Barton
Approved by:	Craig Topper
Differential Revision:	http://reviews.llvm.org/D63782

llvm-svn: 370228
2019-08-28 16:33:36 +00:00
Peter Collingbourne 2452d7030b IR. Change strip* family of functions to not look through aliases.
I noticed another instance of the issue where references to aliases were
being replaced with aliasees, this time in InstCombine. In the instance that
I saw it turned out to be only a QoI issue (a symbol ended up being missing
from the symbol table due to the last reference to the alias being removed,
preventing HWASAN from symbolizing a global reference), but it could easily
have manifested as incorrect behaviour.

Since this is the third such issue encountered (previously: D65118, D65314)
it seems to be time to address this common error/QoI issue once and for all
and make the strip* family of functions not look through aliases.

Includes a test for the specific issue that I saw, but no doubt there are
other similar bugs fixed here.

As with D65118 this has been tested to make sure that the optimization isn't
load bearing. I built Clang, Chromium for Linux, Android and Windows as well
as the test-suite and there were no size regressions.

Differential Revision: https://reviews.llvm.org/D66606

llvm-svn: 369697
2019-08-22 19:56:14 +00:00
Jonas Devlieghere 0eaee545ee [llvm] Migrate llvm::make_unique to std::make_unique
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

llvm-svn: 369013
2019-08-15 15:54:37 +00:00