945 Commits

Author SHA1 Message Date
Phoebe Wang
f63a805a4e Revert "[X86][MS] Change the alignment of f80 to 16 bytes on Windows 32bits to match with ICC"
This reverts commit 1bb0caf561688681be67cc91560348c9e43fcbf3.
2022-01-15 10:54:38 +08:00
Phoebe Wang
1bb0caf561 [X86][MS] Change the alignment of f80 to 16 bytes on Windows 32bits to match with ICC
MSVC currently doesn't support 80 bits long double. ICC supports it when
the option `/Qlong-double` is specified. Changing the alignment of f80
to 16 bytes so that we can be compatible with ICC's option.

Reviewed By: rnk, craig.topper

Differential Revision: https://reviews.llvm.org/D115942
2022-01-12 17:50:37 +08:00
Nick Desaulniers
79ebc3b0dd [llvm][test] rewrite callbr to use i rather than X constraint NFC
In D115311, we're looking to modify clang to emit i constraints rather
than X constraints for callbr's indirect destinations. Prior to doing
so, update all of the existing tests in llvm/ to match.

Reviewed By: void, jyknight

Differential Revision: https://reviews.llvm.org/D115410
2022-01-11 11:31:08 -08:00
Nikita Popov
eddd5be1df [BitCode] Autoupgrade inline asm elementtype attribute
This is the autoupgrade part of D116531. If old bitcode is missing
the elementtype attribute for indirect inline asm constraints,
automatically add it. As usual, this only works when upgrading
in typed mode, we haven't figured out upgrade in opaque mode yet.
2022-01-06 15:13:01 +01:00
Fraser Cormack
d762794040 [IR] Allow the 'align' param attr on vectors of pointers
This patch extends the available uses of the 'align' parameter attribute
to include vectors of pointers. The attribute specifies pointer
alignment element-wise.

This change was previously requested and discussed in D87304.

The vector predication (VP) intrinsics intend to use this for scatter
and gather operations, as they lack the explicit alignment parameter
that the masked versions use.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D115161
2022-01-03 12:32:46 +00:00
Roman Lebedev
62b1682570
[Opaqueptrs][IR Serialization] Improve inlineasm [de]serialization
The bitcode reader expected that the pointers are typed,
so that it can extract the function type for the assembly
so `bitc::CST_CODE_INLINEASM` did not explicitly store said function type.

I'm not really sure how the upgrade path will look for existing bitcode,
but i think we can easily support opaque pointers going forward,
by simply storing the function type.

Reviewed By: #opaque-pointers, nikic

Differential Revision: https://reviews.llvm.org/D116341
2021-12-30 13:54:37 +03:00
Roman Lebedev
d5a4d6a497
[BitcodeReader] propagateAttributeTypes(): fix opaque pointer handling
Can't get the pointee type of an opaque pointer,
but in that case said attributes must already be typed,
so just don't try to rewrite them if they already are.
2021-12-28 22:06:51 +03:00
Sami Tolvanen
5dc8aaac39 [llvm][IR] Add no_cfi constant
With Control-Flow Integrity (CFI), the LowerTypeTests pass replaces
function references with CFI jump table references, which is a problem
for low-level code that needs the address of the actual function body.

For example, in the Linux kernel, the code that sets up interrupt
handlers needs to take the address of the interrupt handler function
instead of the CFI jump table, as the jump table may not even be mapped
into memory when an interrupt is triggered.

This change adds the no_cfi constant type, which wraps function
references in a value that LowerTypeTestsModule::replaceCfiUses does not
replace.

Link: https://github.com/ClangBuiltLinux/linux/issues/1353

Reviewed By: nickdesaulniers, pcc

Differential Revision: https://reviews.llvm.org/D108478
2021-12-20 12:55:32 -08:00
Mingming Liu
09a704c5ef [LTO] Ignore unreachable virtual functions in WPD in hybrid LTO.
Differential Revision: https://reviews.llvm.org/D115492
2021-12-14 20:18:04 +00:00
Cullen Rhodes
698584f89b [IR] Remove unbounded as possible value for vscale_range minimum
The default for min is changed to 1. The behaviour of -mvscale-{min,max}
in Clang is also changed such that 16 is the max vscale when targeting
SVE and no max is specified.

Reviewed By: sdesmalen, paulwalker-arm

Differential Revision: https://reviews.llvm.org/D113294
2021-12-07 09:52:21 +00:00
Zarko Todorovski
7f7dac7126 [NFC][llvm] Inclusive language: reword uses of sanity test and check
Part of continuing work to use more inclusive language. Reworded uses
of sanity check and sanity test in llvm/test/
2021-11-25 07:21:42 -05:00
David Sherwood
2a48b6993a [IR] In ConstantFoldShuffleVectorInstruction use zeroinitializer for splats of 0
When creating a splat of 0 for scalable vectors we tend to create them
with using a combination of shufflevector and insertelement, i.e.

shufflevector (<vscale x 4 x i32> insertelement (<vscale x 4 x i32> poison, i32 0, i32 0),
               <vscale x 4 x i32> poison, <vscale x 4 x i32> zeroinitializer)

However, for the case of a zero splat we can actually just replace the
above with zeroinitializer instead. This makes the IR a lot simpler and
easier to read. I have changed ConstantFoldShuffleVectorInstruction to
use zeroinitializer when creating a splat of integer 0 or FP +0.0 values.

Differential Revision: https://reviews.llvm.org/D113394
2021-11-10 09:42:58 +00:00
Arthur Eubanks
05963a3d66 Revert "[DebugInfo] Enforce implicit constraints on distinct MDNodes"
This reverts commit ee7652569854af567ba83e5255d70e80cc8619a1.

Causes crashes, see comments in D104827.
2021-11-09 14:27:55 -08:00
Scott Linder
ee76525698 [DebugInfo] Enforce implicit constraints on distinct MDNodes
Add UNIQUED and DISTINCT properties in Metadata.def and use them to
implement restrictions on the `distinct` property of MDNodes:

* DIExpression can currently be parsed from IR or read from bitcode
  as `distinct`, but this property is silently dropped when printing
  to IR. This causes accepted IR to fail to round-trip. As DIExpression
  appears inline at each use in the canonical form of IR, it cannot
  actually be `distinct` anyway, as there is no syntax to describe it.
* Similarly, DIArgList is conceptually always uniqued. It is currently
  restricted to only appearing in contexts where there is no syntax for
  `distinct`, but for consistency it is treated equivalently to
  DIExpression in this patch.
* DICompileUnit is already restricted to always being `distinct`, but
  along with adding general support for the inverse restriction I went
  ahead and described this in Metadata.def and updated the parser to be
  general. Future nodes which have this restriction can share this
  support.

The new UNIQUED property applies to DIExpression and DIArgList, and
forbids them to be `distinct`. It also implies they are canonically
printed inline at each use, rather than via MDNode ID.

The new DISTINCT property applies to DICompileUnit, and requires it to
be `distinct`.

A potential alternative change is to forbid the non-inline syntax for
DIExpression entirely, as is done with DIArgList implicitly by requiring
it appear in the context of a function. For example, we would forbid:

    !named = !{!0}
    !0 = !DIExpression()

Instead we would only accept the equivalent inlined version:

    !named = !{!DIExpression()}

This essentially removes the ability to create a `distinct` DIExpression
by construction, as there is no syntax for `distinct` inline. If this
patch is accepted as-is, the result would be that the non-canonical
version is accepted, but the following would be an error and produce a diagnostic:

    !named = !{!0}
    ; error: 'distinct' not allowed for !DIExpression()
    !0 = distinct !DIExpression()

Also update some documentation to consistently use the inline syntax for
DIExpression, and to describe the restrictions on `distinct` for nodes
where applicable.

Reviewed By: StephenTozer, t-tye

Differential Revision: https://reviews.llvm.org/D104827
2021-11-09 18:19:11 +00:00
Yonghong Song
3466e00716 Reland "[Attr] support btf_type_tag attribute"
This is to revert commit f95bd18b5faa (Revert "[Attr] support
btf_type_tag attribute") plus a bug fix.

Previous change failed to handle cases like below:
    $ cat reduced.c
    void a(*);
    void a() {}
    $ clang -c reduced.c -O2 -g

In such cases, during clang IR generation, for function a(),
CGCodeGen has numParams = 1 for FunctionType. But for
FunctionTypeLoc we have FuncTypeLoc.NumParams = 0. By using
FunctionType.numParams as the bound to access FuncTypeLoc
params, a random crash is triggered. The bug fix is to
check against FuncTypeLoc.NumParams before accessing
FuncTypeLoc.getParam(Idx).

Differential Revision: https://reviews.llvm.org/D111199
2021-11-05 11:25:17 -07:00
Martin Storsjö
f95bd18b5f Revert "[Attr] support btf_type_tag attribute"
This reverts commits 737e4216c537c33aab8ec51880f06b8a54325b94 and
ce7ac9e66aba2b937b3d3b5505ce6cc75dcc56ac.

After those commits, the compiler can crash with a reduced
testcase like this:

$ cat reduced.c
void a(*);
void a() {}
$ clang -c reduced.c -O2 -g
2021-11-05 10:36:40 +02:00
Yonghong Song
737e4216c5 [Attr] support btf_type_tag attribute
This patch added clang codegen and llvm support
for btf_type_tag support. Currently, btf_type_tag
attribute info is preserved in DebugInfo IR only for
pointer types associated with typedef, global variable
and function declaration. Eventually, such information
is emitted to dwarf.

The following is an example:
  $ cat test.c
  #define __tag __attribute__((btf_type_tag("tag")))
  int __tag *g;
  $ clang -O2 -g -c test.c
  $ llvm-dwarfdump --debug-info test.o
  ...
  0x0000001e:   DW_TAG_variable
                  DW_AT_name      ("g")
                  DW_AT_type      (0x00000033 "int *")
                  DW_AT_external  (true)
                  DW_AT_decl_file ("/home/yhs/test.c")
                  DW_AT_decl_line (2)
                  DW_AT_location  (DW_OP_addr 0x0)

  0x00000033:   DW_TAG_pointer_type
                  DW_AT_type      (0x00000042 "int")

  0x00000038:     DW_TAG_LLVM_annotation
                    DW_AT_name    ("btf_type_tag")
                    DW_AT_const_value     ("tag")

  0x00000041:     NULL

  0x00000042:   DW_TAG_base_type
                  DW_AT_name      ("int")
                  DW_AT_encoding  (DW_ATE_signed)
                  DW_AT_byte_size (0x04)

  0x00000049:   NULL

Basically, a DW_TAG_LLVM_annotation tag will be inserted
under DW_TAG_pointer_type tag if that pointer has a btf_type_tag
associated with it.

Differential Revision: https://reviews.llvm.org/D111199
2021-11-04 14:23:31 -07:00
Itay Bookstein
848812a55e [Verifier] Add verification logic for GlobalIFuncs
Verify that the resolver exists, that it is a defined
Function, and that its return type matches the ifunc's
type. Add corresponding check to BitcodeReader, change
clang to emit the correct type, and fix tests to comply.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D112349
2021-10-31 20:00:57 -07:00
Yonghong Song
f6811cec84 [DebugInfo] Support typedef with btf_decl_tag attributes
Clang patch ([1]) added support for btf_decl_tag attributes with typedef
types. This patch added llvm support including dwarf generation.
For example, for typedef
   typedef unsigned * __u __attribute__((btf_decl_tag("tag1")));
   __u u;
the following shows llvm-dwarfdump result:
   0x00000033:   DW_TAG_typedef
                   DW_AT_type      (0x00000048 "unsigned int *")
                   DW_AT_name      ("__u")
                   DW_AT_decl_file ("/home/yhs/work/tests/llvm/btf_tag/t.c")
                   DW_AT_decl_line (1)

   0x0000003e:     DW_TAG_LLVM_annotation
                     DW_AT_name    ("btf_decl_tag")
                     DW_AT_const_value     ("tag1")

   0x00000047:     NULL

  [1] https://reviews.llvm.org/D110127

Differential Revision: https://reviews.llvm.org/D110129
2021-10-21 08:42:58 -07:00
Yonghong Song
325d000765 [NFC][Attr] rename attribute btf_tag to btf_decl_tag
Per discussion in https://reviews.llvm.org/D111199,
the existing btf_tag attribute will be renamed to
btf_decl_tag. This patch mostly updated the Bitcode and
DebugInfo test cases with new attribute name.

Differential Revision: https://reviews.llvm.org/D111591
2021-10-11 20:57:31 -07:00
Qiu Chaofan
573531fb1f Fix typo of colon to semicolon in lit tests 2021-10-09 10:03:50 +08:00
Arthur Eubanks
05392466f0 Reland [IR] Increase max alignment to 4GB
Currently the max alignment representable is 1GB, see D108661.
Setting the align of an object to 4GB is desirable in some cases to make sure the lower 32 bits are clear which can be used for some optimizations, e.g. https://crbug.com/1016945.

This uses an extra bit in instructions that carry an alignment. We can store 15 bits of "free" information, and with this change some instructions (e.g. AtomicCmpXchgInst) use 14 bits.
We can increase the max alignment representable above 4GB (up to 2^62) since we're only using 33 of the 64 values, but I've just limited it to 4GB for now.

The one place we have to update the bitcode format is for the alloca instruction. It stores its alignment into 5 bits of a 32 bit bitfield. I've added another field which is 8 bits and should be future proof for a while. For backward compatibility, we check if the old field has a value and use that, otherwise use the new field.

Updating clang's max allowed alignment will come in a future patch.

Reviewed By: hans

Differential Revision: https://reviews.llvm.org/D110451
2021-10-06 13:29:23 -07:00
Arthur Eubanks
569346f274 Revert "Reland [IR] Increase max alignment to 4GB"
This reverts commit 8d64314ffea55f2ad94c1b489586daa8ce30f451.
2021-10-06 11:38:11 -07:00
Arthur Eubanks
8d64314ffe Reland [IR] Increase max alignment to 4GB
Currently the max alignment representable is 1GB, see D108661.
Setting the align of an object to 4GB is desirable in some cases to make sure the lower 32 bits are clear which can be used for some optimizations, e.g. https://crbug.com/1016945.

This uses an extra bit in instructions that carry an alignment. We can store 15 bits of "free" information, and with this change some instructions (e.g. AtomicCmpXchgInst) use 14 bits.
We can increase the max alignment representable above 4GB (up to 2^62) since we're only using 33 of the 64 values, but I've just limited it to 4GB for now.

The one place we have to update the bitcode format is for the alloca instruction. It stores its alignment into 5 bits of a 32 bit bitfield. I've added another field which is 8 bits and should be future proof for a while. For backward compatibility, we check if the old field has a value and use that, otherwise use the new field.

Updating clang's max allowed alignment will come in a future patch.

Reviewed By: hans

Differential Revision: https://reviews.llvm.org/D110451
2021-10-06 11:03:51 -07:00
Arthur Eubanks
72cf8b6044 Revert "[IR] Increase max alignment to 4GB"
This reverts commit df84c1fe78130a86445d57563dea742e1b85156a.

Breaks some bots
2021-10-06 10:21:35 -07:00
Arthur Eubanks
df84c1fe78 [IR] Increase max alignment to 4GB
Currently the max alignment representable is 1GB, see D108661.
Setting the align of an object to 4GB is desirable in some cases to make sure the lower 32 bits are clear which can be used for some optimizations, e.g. https://crbug.com/1016945.

This uses an extra bit in instructions that carry an alignment. We can store 15 bits of "free" information, and with this change some instructions (e.g. AtomicCmpXchgInst) use 14 bits.
We can increase the max alignment representable above 4GB (up to 2^62) since we're only using 33 of the 64 values, but I've just limited it to 4GB for now.

The one place we have to update the bitcode format is for the alloca instruction. It stores its alignment into 5 bits of a 32 bit bitfield. I've added another field which is 8 bits and should be future proof for a while. For backward compatibility, we check if the old field has a value and use that, otherwise use the new field.

Updating clang's max allowed alignment will come in a future patch.

Reviewed By: hans

Differential Revision: https://reviews.llvm.org/D110451
2021-10-06 09:54:14 -07:00
modimo
20faf78919 [ThinLTO] Add noRecurse and noUnwind thinlink function attribute propagation
Thinlink provides an opportunity to propagate function attributes across modules, enabling additional propagation opportunities.

This change propagates (currently default off, turn on with `disable-thinlto-funcattrs=1`) noRecurse and noUnwind based off of function summaries of the prevailing functions in bottom-up call-graph order. Testing on clang self-build:
1. There's a 35-40% increase in noUnwind functions due to the additional propagation opportunities.
2. Throughput is measured at 10-15% increase in thinlink time which itself is 1.5% of E2E link time.

Implementation-wise this adds the following summary function attributes:
1. noUnwind: function is noUnwind
2. mayThrow: function contains a non-call instruction that `Instruction::mayThrow` returns true on (e.g. windows SEH instructions)
3. hasUnknownCall: function contains calls that don't make it into the summary call-graph thus should not be propagated from (e.g. indirect for now, could add no-opt functions as well)

Testing:
Clang self-build passes and 2nd stage build passes check-all
ninja check-all with newly added tests passing

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D36850
2021-09-27 12:28:07 -07:00
Alok Kumar Sharma
a5b72abc9e [DebugInfo] Enhance DIImportedEntity to accept children entities
New field `elements` is added to '!DIImportedEntity', representing
list of aliased entities.
This is needed to dump optimized debugging information where all names
in a module are imported, but a few names are imported with overriding
aliases.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D109343
2021-09-16 10:41:55 +05:30
guopeilin
749ddd25e9 [BitcodeReader] Delay select until all constants resolved
Like the shuffle, we should treat the select delayed so that
all constants can be resolved.

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D109053
2021-09-11 18:51:35 +08:00
Yonghong Song
1bebc31c61 [DebugInfo] generate btf_tag annotations for func parameters
Generate btf_tag annotations for function parameters.
A field "annotations" is introduced to DILocalVariable, and
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates how
annotations are encoded in IR:
    distinct !DILocalVariable(name: "info",, arg: 1, ..., annotations: !10)
    !10 = !{!11, !12}
    !11 = !{!"btf_tag", !"a"}
    !12 = !{!"btf_tag", !"b"}

Differential Revision: https://reviews.llvm.org/D106620
2021-08-26 14:18:30 -07:00
Yonghong Song
30c288489a [DebugInfo] generate btf_tag annotations for DIGlobalVariable
Generate btf_tag annotations for DIGlobalVariable.
A field "annotations" is introduced to DIGlobalVariable, and
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates how
annotations are encoded in IR:
    distinct !DIGlobalVariable(..., annotations: !10)
    !10 = !{!11, !12}
    !11 = !{!"btf_tag", !"a"}
    !12 = !{!"btf_tag", !"b"}

Differential Revision: https://reviews.llvm.org/D106619
2021-08-26 10:03:44 -07:00
Yonghong Song
d383df32c0 [DebugInfo] generate btf_tag annotations for DISubprogram types
Generate btf_tag annotations for DISubprogram types.
A field "annotations" is introduced to DISubprogram, and
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates how
annotations are encoded in IR:
    distinct !DISubprogram(..., annotations: !10)
    !10 = !{!11, !12}
    !11 = !{!"btf_tag", !"a"}
    !12 = !{!"btf_tag", !"b"}

Differential Revision: https://reviews.llvm.org/D106618
2021-08-26 08:24:19 -07:00
Roman Lebedev
564d85e090
The maximal representable alignment in LLVM IR is 1GiB, not 512MiB
In LLVM IR, `AlignmentBitfieldElementT` is 5-bit wide
But that means that the maximal alignment exponent is `(1<<5)-2`,
which is `30`, not `29`. And indeed, alignment of `1073741824`
roundtrips IR serialization-deserialization.

While this doesn't seem all that important, this doubles
the maximal supported alignment from 512MiB to 1GiB,
and there's actually one noticeable use-case for that;
On X86, the huge pages can have sizes of 2MiB and 1GiB (!).

So while this doesn't add support for truly huge alignments,
which i think we can easily-ish do if wanted, i think this adds
zero-cost support for a not-trivially-dismissable case.

I don't believe we need any upgrade infrastructure,
and since we don't explicitly record the IR version,
we don't need to bump one either.

As @craig.topper speculates in D108661#2963519,
this might be an artificial limit imposed by the original implementation
of the `getAlignment()` functions.

Differential Revision: https://reviews.llvm.org/D108661
2021-08-26 12:53:39 +03:00
Yonghong Song
430e223881 [DebugInfo] generate btf_tag annotations for DIDerived types
Generate btf_tag annotations for DIDrived types. More specifically,
clang frontend generates the btf_tag annotations for record
fields. The annotations are represented as an DINodeArray
in DebugInfo. The following example illustrate how
annotations are encoded in IR:
      distinct !DIDerivedType(tag: DW_TAG_member, ..., annotations: !10)
      !10 = !{!11, !12}
      !11 = !{!"btf_tag", !"a"}
      !12 = !{!"btf_tag", !"b"}

Differential Revision: https://reviews.llvm.org/D106616
2021-08-20 12:06:37 -07:00
Alexander Potapenko
b0391dfc73 [clang][Codegen] Introduce the disable_sanitizer_instrumentation attribute
The purpose of __attribute__((disable_sanitizer_instrumentation)) is to
prevent all kinds of sanitizer instrumentation applied to a certain
function, Objective-C method, or global variable.

The no_sanitize(...) attribute drops instrumentation checks, but may
still insert code preventing false positive reports. In some cases
though (e.g. when building Linux kernel with -fsanitize=kernel-memory
or -fsanitize=thread) the users may want to avoid any kind of
instrumentation.

Differential Revision: https://reviews.llvm.org/D108029
2021-08-20 14:01:06 +02:00
Yonghong Song
0b32dca12e Reland [DebugInfo] generate btf_tag annotations for DIComposite types
Clang patch D106614 added attribute btf_tag support. This patch
generates btf_tag annotations for DIComposite types.
A field "annotations" is introduced to DIComposite, and the
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates
how annotations are encoded in IR:
  distinct !DICompositeType(..., annotations: !10)
  !10 = !{!11, !12}
  !11 = !{!"btf_tag", !"a"}
  !12 = !{!"btf_tag", !"b"}
Each btf_tag annotation is represented as a 2D array of
meta strings. Each record may have more than one
btf_tag annotations, as in the above example.

Reland with additional fixes for llvm/unittests/IR/DebugTypeODRUniquingTest.cpp.

Differential Revision: https://reviews.llvm.org/D106615
2021-08-19 17:33:50 -07:00
Yonghong Song
c1169b8bd3 Revert "[DebugInfo] generate btf_tag annotations for DIComposite types"
This reverts commit 2fded193e7a8fb5bd8fb339f00fd9de686390530.

Builtbot reports some test failures. Revert now so I can take time
to fix the issues.
2021-08-19 15:54:38 -07:00
Yonghong Song
2fded193e7 [DebugInfo] generate btf_tag annotations for DIComposite types
Clang patch D106614 added attribute btf_tag support. This patch
generates btf_tag annotations for DIComposite types.
A field "annotations" is introduced to DIComposite, and the
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates
how annotations are encoded in IR:
  distinct !DICompositeType(..., annotations: !10)
  !10 = !{!11, !12}
  !11 = !{!"btf_tag", !"a"}
  !12 = !{!"btf_tag", !"b"}
Each btf_tag annotation is represented as a 2D array of
meta strings. Each record may have more than one
btf_tag annotations, as in the above example.

Differential Revision: https://reviews.llvm.org/D106615
2021-08-19 15:37:44 -07:00
Fangrui Song
3924877932 [IR] Rename comdat noduplicates to comdat nodeduplicate
In the textual format, `noduplicates` means no COMDAT/section group
deduplication is performed. Therefore, if both sets of sections are retained, and
they happen to define strong external symbols with the same names,
there will be a duplicate definition linker error.

In PE/COFF, the selection kind lowers to `IMAGE_COMDAT_SELECT_NODUPLICATES`.
The name describes the corollary instead of the immediate semantics.  The name
can cause confusion to other binary formats (ELF, wasm) which have implemented/
want to implement the "no deduplication" selection kind. Rename it to be clearer.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D106319
2021-07-20 12:47:10 -07:00
Nikita Popov
be5af50e7d [BPF] Use elementtype attribute for preserve.array/struct.index intrinsics
Use the elementtype attribute introduced in D105407 for the
llvm.preserve.array/struct.index intrinsics. It carries the
element type of the GEP these intrinsics effectively encode.

This patch:

 * Adds a verifier check that the attribute is required.
 * Adds it in the IRBuilder methods for these intrinsics.
 * Autoupgrades old bitcode without the attribute.
 * Updates the lowering code to use the attribute rather than
   the pointer element type.
 * Updates lots of tests to specify the attribute.
 * Adds -force-opaque-pointers to the intrinsic-array.ll test
   to demonstrate they work now.

https://reviews.llvm.org/D106184
2021-07-17 11:09:18 +02:00
Nikita Popov
c191035f42 [IR] Add elementtype attribute
This implements the elementtype attribute specified in D105407. It
just adds the attribute and the specified verifier rules, but
doesn't yet make use of it anywhere.

Differential Revision: https://reviews.llvm.org/D106008
2021-07-15 18:04:26 +02:00
Jonas Devlieghere
52b5491a21 Revert "[DebugInfo] Enforce implicit constraints on distinct MDNodes"
This reverts commit 8cd35ad854ab4458fd509447359066ea3578b494.

It breaks `TestMembersAndLocalsWithSameName.py` on GreenDragon and
Mikael Holmén points out in D104827 that bitcode files created with the
patch cannot be parsed with binaries built before it.
2021-07-02 15:57:07 -07:00
Alex Richardson
c142c06c19 Place the BlockAddress type in the address space of the containing function
While this should not matter for most architectures (where the program
address space is 0), it is important for CHERI (and therefore Arm Morello).
We use address space 200 for all of our code pointers and without this
change we assert in the SelectionDAG handling of BlockAddress nodes.

It is also useful for AVR: previously programs targeting
AVR that attempt to read their own machine code
via a pointer to a label would instead read from RAM
using a pointer relative to the the start of program flash.

Reviewed By: dylanmckay, theraven
Differential Revision: https://reviews.llvm.org/D48803
2021-07-02 12:17:55 +01:00
Scott Linder
8cd35ad854 [DebugInfo] Enforce implicit constraints on distinct MDNodes
Add UNIQUED and DISTINCT properties in Metadata.def and use them to
implement restrictions on the `distinct` property of MDNodes:

* DIExpression can currently be parsed from IR or read from bitcode
  as `distinct`, but this property is silently dropped when printing
  to IR. This causes accepted IR to fail to round-trip. As DIExpression
  appears inline at each use in the canonical form of IR, it cannot
  actually be `distinct` anyway, as there is no syntax to describe it.
* Similarly, DIArgList is conceptually always uniqued. It is currently
  restricted to only appearing in contexts where there is no syntax for
  `distinct`, but for consistency it is treated equivalently to
  DIExpression in this patch.
* DICompileUnit is already restricted to always being `distinct`, but
  along with adding general support for the inverse restriction I went
  ahead and described this in Metadata.def and updated the parser to be
  general. Future nodes which have this restriction can share this
  support.

The new UNIQUED property applies to DIExpression and DIArgList, and
forbids them to be `distinct`. It also implies they are canonically
printed inline at each use, rather than via MDNode ID.

The new DISTINCT property applies to DICompileUnit, and requires it to
be `distinct`.

A potential alternative change is to forbid the non-inline syntax for
DIExpression entirely, as is done with DIArgList implicitly by requiring
it appear in the context of a function. For example, we would forbid:

    !named = !{!0}
    !0 = !DIExpression()

Instead we would only accept the equivalent inlined version:

    !named = !{!DIExpression()}

This essentially removes the ability to create a `distinct` DIExpression
by construction, as there is no syntax for `distinct` inline. If this
patch is accepted as-is, the result would be that the non-canonical
version is accepted, but the following would be an error and produce a diagnostic:

    !named = !{!0}
    ; error: 'distinct' not allowed for !DIExpression()
    !0 = distinct !DIExpression()

Also update some documentation to consistently use the inline syntax for
DIExpression, and to describe the restrictions on `distinct` for nodes
where applicable.

Reviewed By: StephenTozer, t-tye

Differential Revision: https://reviews.llvm.org/D104827
2021-06-28 21:20:04 +00:00
Nikita Popov
aad87328fa [AsmWriter] Properly handle uselistorder for global symbols
Currently, AsmWriter will stick uselistorder directives for global
values inside individual functions. This doesn't make a lot of sense,
and interacts badly with D104950, as use list order adjustments will
be performed while still working on a forward reference.

This patch instead always prints uselistorder directives for globals
at the module level. This isn't really compatible with the previously
used implementation approach. Rather than walking through all values
again, use the OrderMap (after stabilizing its order) to go through
all values and compute the use list shuffles for them. Classify them
per-function, or nullptr for globals.

Even independently of D104950, this seems to fix a few
verify-uselistorder failures. Conveniently, there is even a
pre-existing failing test that this fixes.

Differential Revision: https://reviews.llvm.org/D104976
2021-06-28 23:15:32 +02:00
Nathan Chancellor
4ae0ab095b
[BitCode] Add noprofile to getAttrFromCode()
After D104475 / D104658, building the Linux kernel with ThinLTO is
broken:

ld.lld: error: Unknown attribute kind (73) (Producer: 'LLVM13.0.0git'
Reader: 'LLVM 13.0.0git')

getAttrFromCode() has never handled this attribute so it is written
during the ThinLTO phase but it cannot be handled during the linking
phase.

Add noprofile to getAttrFromCode() so that disassembly works properly.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D104995
2021-06-27 11:59:57 -07:00
Florian Hahn
34cccdaed7
[BitcodeReader] Validate Strtab before accessing.
This fixes a crash with invalid bitcode files that have records
referencing names in Strtab, but Strtab is not present or the index is
out-of-bounds.

This fixes the following clusterfuzz issue:
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=29895

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D95554
2021-06-22 14:52:16 +01:00
Bjorn Pettersson
4c7f820b2b Update @llvm.powi to handle different int sizes for the exponent
This can be seen as a follow up to commit 0ee439b705e82a4fe20e2,
that changed the second argument of __powidf2, __powisf2 and
__powitf2 in compiler-rt from si_int to int. That was to align with
how those runtimes are defined in libgcc.
One thing that seem to have been missing in that patch was to make
sure that the rest of LLVM also handle that the argument now depends
on the size of int (not using the si_int machine mode for 32-bit).
When using __builtin_powi for a target with 16-bit int clang crashed.
And when emitting libcalls to those rtlib functions, typically when
lowering @llvm.powi), the backend would always prepare the exponent
argument as an i32 which caused miscompiles when the rtlib was
compiled with 16-bit int.

The solution used here is to use an overloaded type for the second
argument in @llvm.powi. This way clang can use the "correct" type
when lowering __builtin_powi, and then later when emitting the libcall
it is assumed that the type used in @llvm.powi matches the rtlib
function.

One thing that needed some extra attention was that when vectorizing
calls several passes did not support that several arguments could
be overloaded in the intrinsics. This patch allows overload of a
scalar operand by adding hasVectorInstrinsicOverloadedScalarOpd, with
an entry for powi.

Differential Revision: https://reviews.llvm.org/D99439
2021-06-17 09:38:28 +02:00
Arthur Eubanks
ad90a6be21 [OpaquePtr] Create new bitcode encoding for atomicrmw
Since the opaque pointer type won't contain the pointee type, we need to
separately encode the value type for an atomicrmw.

Emit this new code for atomicrmw.

Handle this new code and the old one in the bitcode reader.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D103123
2021-05-25 16:30:34 -07:00
Marco Elver
280333021e [SanitizeCoverage] Add support for NoSanitizeCoverage function attribute
We really ought to support no_sanitize("coverage") in line with other
sanitizers. This came up again in discussions on the Linux-kernel
mailing lists, because we currently do workarounds using objtool to
remove coverage instrumentation. Since that support is only on x86, to
continue support coverage instrumentation on other architectures, we
must support selectively disabling coverage instrumentation via function
attributes.

Unfortunately, for SanitizeCoverage, it has not been implemented as a
sanitizer via fsanitize= and associated options in Sanitizers.def, but
rolls its own option fsanitize-coverage. This meant that we never got
"automatic" no_sanitize attribute support.

Implement no_sanitize attribute support by special-casing the string
"coverage" in the NoSanitizeAttr implementation. To keep the feature as
unintrusive to existing IR generation as possible, define a new negative
function attribute NoSanitizeCoverage to propagate the information
through to the instrumentation pass.

Fixes: https://bugs.llvm.org/show_bug.cgi?id=49035

Reviewed By: vitalybuka, morehouse

Differential Revision: https://reviews.llvm.org/D102772
2021-05-25 12:57:14 +02:00