[NFC] Pass a reference to CodeGenFunction to methods of LValue and
AggValueSlot

This is needed for the pointer authentication work we plan to do in the
near future.

https://github.com/apple/llvm-pr

[NFC] Pass a reference to CodeGenFunction to methods of LValue and
AggValueSlot

This is needed for the pointer authentication work we plan to do in the
near future.

https://github.com/apple/llvm-project/blob/a63a81bd9911f87a0b5dcd5bdd7ccdda7124af87/clang/docs/PointerAuthentication.rst

show more ...

IRGen: Call SetLLVMFunctionAttributes{,ForDefinition} on __cfi_check_fail.

This has the main effect of causing target-cpu and target-features to be set
on __cfi_check_fail, causing the function to b

IRGen: Call SetLLVMFunctionAttributes{,ForDefinition} on __cfi_check_fail.

This has the main effect of causing target-cpu and target-features to be set
on __cfi_check_fail, causing the function to become ABI-compatible with other
functions in the case where these attributes affect ABI (e.g. reserve-x18).

Technically we only need to call SetLLVMFunctionAttributes to get the target-*
attributes set, but since we're creating a definition we probably ought to
call the ForDefinition function as well.

Fixes PR44094.

Differential Revision: https://reviews.llvm.org/D70692

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[NFC] Refactor representation of materialized temporaries

Summary:
this patch refactor representation of materialized temporaries to prevent an issue raised by rsmith in https://reviews.llvm.org/D63

[NFC] Refactor representation of materialized temporaries

Summary:
this patch refactor representation of materialized temporaries to prevent an issue raised by rsmith in https://reviews.llvm.org/D63640#inline-612718

Reviewers: rsmith, martong, shafik

Reviewed By: rsmith

Subscribers: thakis, sammccall, ilya-biryukov, rnkovacs, arphaman, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D69360

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Revert "[NFC] Refactor representation of materialized temporaries"

This reverts commit 08ea1ee2db5f9d6460fef1d79d0d1d1a5eb78982.
It broke ./ClangdTests/FindExplicitReferencesTest.All
on the bots, se

Revert "[NFC] Refactor representation of materialized temporaries"

This reverts commit 08ea1ee2db5f9d6460fef1d79d0d1d1a5eb78982.
It broke ./ClangdTests/FindExplicitReferencesTest.All
on the bots, see comments on https://reviews.llvm.org/D69360

show more ...

[NFC] Refactor representation of materialized temporaries

Summary:
this patch refactor representation of materialized temporaries to prevent an issue raised by rsmith in https://reviews.llvm.org/D63

[NFC] Refactor representation of materialized temporaries

Summary:
this patch refactor representation of materialized temporaries to prevent an issue raised by rsmith in https://reviews.llvm.org/D63640#inline-612718

Reviewers: rsmith, martong, shafik

Reviewed By: rsmith

Subscribers: rnkovacs, arphaman, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D69360

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[BPF] Restrict preserve_access_index attribute to C only

This patch is a follow-up for commit 4e2ce228ae79
[BPF] Add preserve_access_index attribute for record definition
to restrict attribute for

[BPF] Restrict preserve_access_index attribute to C only

This patch is a follow-up for commit 4e2ce228ae79
[BPF] Add preserve_access_index attribute for record definition
to restrict attribute for C only. A new test case is added
to check for this restriction.

Additional code polishing is done based on
Aaron Ballman's suggestion in https://reviews.llvm.org/D69759/new/.

Differential Revision: https://reviews.llvm.org/D70257

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[BPF] Add preserve_access_index attribute for record definition

This is a resubmission for the previous reverted commit
943436040121 with the same subject. This commit fixed the
segfault issue and a

[BPF] Add preserve_access_index attribute for record definition

This is a resubmission for the previous reverted commit
943436040121 with the same subject. This commit fixed the
segfault issue and addressed additional review comments.

This patch introduced a new bpf specific attribute which can
be added to struct or union definition. For example,
struct s { ... } __attribute__((preserve_access_index));
union u { ... } __attribute__((preserve_access_index));
The goal is to simplify user codes for cases
where preserve access index happens for certain struct/union,
so user does not need to use clang __builtin_preserve_access_index
for every members.

The attribute has no effect if -g is not specified.

When the attribute is specified and -g is specified, any member
access defined by that structure or union, including array subscript
access and inner records, will be preserved through
__builtin_preserve_{array,struct,union}_access_index()
IR intrinsics, which will enable relocation generation
in bpf backend.

The following is an example to illustrate the usage:
-bash-4.4$ cat t.c
#define __reloc__ __attribute__((preserve_access_index))
struct s1 {
int c;
} __reloc__;

struct s2 {
union {
struct s1 b[3];
};
} __reloc__;

struct s3 {
struct s2 a;
} __reloc__;

int test(struct s3 *arg) {
return arg->a.b[2].c;
}
-bash-4.4$ clang -target bpf -g -S -O2 t.c

A relocation with access string "0:0:0:0:2:0" will be generated
representing access offset of arg->a.b[2].c.

forward declaration with attribute is also handled properly such
that the attribute is copied and populated in real record definition.

Differential Revision: https://reviews.llvm.org/D69759

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Revert "[BPF] Add preserve_access_index attribute for record definition"

This reverts commit 4a5aa1a7bf8b1714b817ede8e09cd28c0784228a.

There are some other test failures. Investigate them first.

[BPF] Add preserve_access_index attribute for record definition

This patch introduced a new bpf specific attribute which can
be added to struct or union definition. For example,
struct s { ... } _

[BPF] Add preserve_access_index attribute for record definition

This patch introduced a new bpf specific attribute which can
be added to struct or union definition. For example,
struct s { ... } __attribute__((preserve_access_index));
union u { ... } __attribute__((preserve_access_index));
The goal is to simplify user codes for cases
where preserve access index happens for certain struct/union,
so user does not need to use clang __builtin_preserve_access_index
for every members.

The attribute has no effect if -g is not specified.

When the attribute is specified and -g is specified, any member
access defined by that structure or union, including array subscript
access and inner records, will be preserved through
__builtin_preserve_{array,struct,union}_access_index()
IR intrinsics, which will enable relocation generation
in bpf backend.

The following is an example to illustrate the usage:
-bash-4.4$ cat t.c
#define __reloc__ __attribute__((preserve_access_index))
struct s1 {
int c;
} __reloc__;

struct s2 {
union {
struct s1 b[3];
};
} __reloc__;

struct s3 {
struct s2 a;
} __reloc__;

int test(struct s3 *arg) {
return arg->a.b[2].c;
}
-bash-4.4$ clang -target bpf -g -S -O2 t.c

A relocation with access string "0:0:0:0:2:0" will be generated
representing access offset of arg->a.b[2].c.

forward declaration with attribute is also handled properly such
that the attribute is copied and populated in real record definition.

Differential Revision: https://reviews.llvm.org/D69759

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[opaque pointer types] Add element type argument to IRBuilder CreatePreserveStructAccessIndex and CreatePreserveArrayAccessIndex

Summary:
These were the only remaining users of the GetElementPtrInst

[opaque pointer types] Add element type argument to IRBuilder CreatePreserveStructAccessIndex and CreatePreserveArrayAccessIndex

Summary:
These were the only remaining users of the GetElementPtrInst::getGEPReturnType
method that gets the element type from the pointer type.

Remove that method since its now dead.

Reviewers: jyknight, t.p.northover, arsenm

Reviewed By: arsenm

Subscribers: wdng, arsenm, arphaman, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D69756

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[c++20] Add CXXRewrittenBinaryOperator to represent a comparison
operator that is rewritten as a call to multiple other operators.

No functionality change yet: nothing creates these expressions.

ll

[c++20] Add CXXRewrittenBinaryOperator to represent a comparison
operator that is rewritten as a call to multiple other operators.

No functionality change yet: nothing creates these expressions.

llvm-svn: 375305

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Revert Tag CFI-generated data structures with "#pragma clang section" attributes.

This reverts r375022 (git commit e2692b3bc0327606748b6d291b9009d2c845ced5)

llvm-svn: 375069

Tag CFI-generated data structures with "#pragma clang section" attributes.

Differential Revision: https://reviews.llvm.org/D68808

llvm-svn: 375022

[BPF] do compile-once run-everywhere relocation for bitfields

A bpf specific clang intrinsic is introduced:
u32 __builtin_preserve_field_info(member_access, info_kind)
Depending on info_kind, dif

[BPF] do compile-once run-everywhere relocation for bitfields

A bpf specific clang intrinsic is introduced:
u32 __builtin_preserve_field_info(member_access, info_kind)
Depending on info_kind, different information will
be returned to the program. A relocation is also
recorded for this builtin so that bpf loader can
patch the instruction on the target host.
This clang intrinsic is used to get certain information
to facilitate struct/union member relocations.

The offset relocation is extended by 4 bytes to
include relocation kind.
Currently supported relocation kinds are
enum {
FIELD_BYTE_OFFSET = 0,
FIELD_BYTE_SIZE,
FIELD_EXISTENCE,
FIELD_SIGNEDNESS,
FIELD_LSHIFT_U64,
FIELD_RSHIFT_U64,
};
for __builtin_preserve_field_info. The old
access offset relocation is covered by
FIELD_BYTE_OFFSET = 0.

An example:
struct s {
int a;
int b1:9;
int b2:4;
};
enum {
FIELD_BYTE_OFFSET = 0,
FIELD_BYTE_SIZE,
FIELD_EXISTENCE,
FIELD_SIGNEDNESS,
FIELD_LSHIFT_U64,
FIELD_RSHIFT_U64,
};

void bpf_probe_read(void *, unsigned, const void *);
int field_read(struct s *arg) {
unsigned long long ull = 0;
unsigned offset = __builtin_preserve_field_info(arg->b2, FIELD_BYTE_OFFSET);
unsigned size = __builtin_preserve_field_info(arg->b2, FIELD_BYTE_SIZE);
#ifdef USE_PROBE_READ
bpf_probe_read(&ull, size, (const void *)arg + offset);
unsigned lshift = __builtin_preserve_field_info(arg->b2, FIELD_LSHIFT_U64);
#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
lshift = lshift + (size << 3) - 64;
#endif
#else
switch(size) {
case 1:
ull = *(unsigned char *)((void *)arg + offset); break;
case 2:
ull = *(unsigned short *)((void *)arg + offset); break;
case 4:
ull = *(unsigned int *)((void *)arg + offset); break;
case 8:
ull = *(unsigned long long *)((void *)arg + offset); break;
}
unsigned lshift = __builtin_preserve_field_info(arg->b2, FIELD_LSHIFT_U64);
#endif
ull <<= lshift;
if (__builtin_preserve_field_info(arg->b2, FIELD_SIGNEDNESS))
return (long long)ull >> __builtin_preserve_field_info(arg->b2, FIELD_RSHIFT_U64);
return ull >> __builtin_preserve_field_info(arg->b2, FIELD_RSHIFT_U64);
}

There is a minor overhead for bpf_probe_read() on big endian.

The code and relocation generated for field_read where bpf_probe_read() is
used to access argument data on little endian mode:
r3 = r1
r1 = 0
r1 = 4 <=== relocation (FIELD_BYTE_OFFSET)
r3 += r1
r1 = r10
r1 += -8
r2 = 4 <=== relocation (FIELD_BYTE_SIZE)
call bpf_probe_read
r2 = 51 <=== relocation (FIELD_LSHIFT_U64)
r1 = *(u64 *)(r10 - 8)
r1 <<= r2
r2 = 60 <=== relocation (FIELD_RSHIFT_U64)
r0 = r1
r0 >>= r2
r3 = 1 <=== relocation (FIELD_SIGNEDNESS)
if r3 == 0 goto LBB0_2
r1 s>>= r2
r0 = r1
LBB0_2:
exit

Compare to the above code between relocations FIELD_LSHIFT_U64 and
FIELD_LSHIFT_U64, the code with big endian mode has four more
instructions.
r1 = 41 <=== relocation (FIELD_LSHIFT_U64)
r6 += r1
r6 += -64
r6 <<= 32
r6 >>= 32
r1 = *(u64 *)(r10 - 8)
r1 <<= r6
r2 = 60 <=== relocation (FIELD_RSHIFT_U64)

The code and relocation generated when using direct load.
r2 = 0
r3 = 4
r4 = 4
if r4 s> 3 goto LBB0_3
if r4 == 1 goto LBB0_5
if r4 == 2 goto LBB0_6
goto LBB0_9
LBB0_6: # %sw.bb1
r1 += r3
r2 = *(u16 *)(r1 + 0)
goto LBB0_9
LBB0_3: # %entry
if r4 == 4 goto LBB0_7
if r4 == 8 goto LBB0_8
goto LBB0_9
LBB0_8: # %sw.bb9
r1 += r3
r2 = *(u64 *)(r1 + 0)
goto LBB0_9
LBB0_5: # %sw.bb
r1 += r3
r2 = *(u8 *)(r1 + 0)
goto LBB0_9
LBB0_7: # %sw.bb5
r1 += r3
r2 = *(u32 *)(r1 + 0)
LBB0_9: # %sw.epilog
r1 = 51
r2 <<= r1
r1 = 60
r0 = r2
r0 >>= r1
r3 = 1
if r3 == 0 goto LBB0_11
r2 s>>= r1
r0 = r2
LBB0_11: # %sw.epilog
exit

Considering verifier is able to do limited constant
propogation following branches. The following is the
code actually traversed.
r2 = 0
r3 = 4 <=== relocation
r4 = 4 <=== relocation
if r4 s> 3 goto LBB0_3
LBB0_3: # %entry
if r4 == 4 goto LBB0_7
LBB0_7: # %sw.bb5
r1 += r3
r2 = *(u32 *)(r1 + 0)
LBB0_9: # %sw.epilog
r1 = 51 <=== relocation
r2 <<= r1
r1 = 60 <=== relocation
r0 = r2
r0 >>= r1
r3 = 1
if r3 == 0 goto LBB0_11
r2 s>>= r1
r0 = r2
LBB0_11: # %sw.epilog
exit

For native load case, the load size is calculated to be the
same as the size of load width LLVM otherwise used to load
the value which is then used to extract the bitfield value.

Differential Revision: https://reviews.llvm.org/D67980

llvm-svn: 374099

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Codegen - silence static analyzer getAs<> null dereference warnings. NFCI.

The static analyzer is warning about potential null dereferences, but in these cases we should be able to use castAs<> dire

Codegen - silence static analyzer getAs<> null dereference warnings. NFCI.

The static analyzer is warning about potential null dereferences, but in these cases we should be able to use castAs<> directly and if not assert will fire for us.

llvm-svn: 373918

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[Alignment][Clang][NFC] Add CharUnits::getAsAlign

Summary:
This is a prerequisite to removing `llvm::GlobalObject::setAlignment(unsigned)`.
This is patch is part of a series to introduce an Alignmen

[Alignment][Clang][NFC] Add CharUnits::getAsAlign

Summary:
This is a prerequisite to removing `llvm::GlobalObject::setAlignment(unsigned)`.
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: jholewinski, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D68274

llvm-svn: 373592

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[Alignment][NFC] Remove AllocaInst::setAlignment(unsigned)

Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llv

[Alignment][NFC] Remove AllocaInst::setAlignment(unsigned)

Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: jholewinski, arsenm, jvesely, nhaehnle, eraman, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68141

llvm-svn: 373207

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Improve code generation for thread_local variables:

Summary:
* Don't bother using a thread wrapper when the variable is known to
have constant initialization.
* Emit the thread wrapper as disca

Improve code generation for thread_local variables:

Summary:
* Don't bother using a thread wrapper when the variable is known to
have constant initialization.
* Emit the thread wrapper as discardable-if-unused in TUs that don't
contain a definition of the thread_local variable.
* Don't emit the thread wrapper at all if the thread_local variable
is unused and discardable; it will be emitted by all TUs that need
it.

Reviewers: rjmccall, jdoerfert

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D67429

llvm-svn: 371767

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Fix for PR43175: compiler crash when trying to emit noncapturable
constant.

If the constexpr variable is partially initialized, the initializer can
be emitted as the structure, not as an array, beca

Fix for PR43175: compiler crash when trying to emit noncapturable
constant.

If the constexpr variable is partially initialized, the initializer can
be emitted as the structure, not as an array, because of some early
optimizations. The llvm variable gets the type from this constant and,
thus, gets the type which is pointer to struct rather than pointer to an
array. We need to convert this type to be truely array, otherwise it may
lead to the compiler crash when trying to emit array subscript
expression.

llvm-svn: 371548

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Implement codegen for MSVC unions with reference members.

Currently, clang accepts a union with a reference member when given the -fms-extensions flag. This change fixes the codegen for this case.

Implement codegen for MSVC unions with reference members.

Currently, clang accepts a union with a reference member when given the -fms-extensions flag. This change fixes the codegen for this case.

Patch by Dominic Ferreira.

llvm-svn: 370052

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hwasan, codegen: Keep more lifetime markers used for hwasan

Reviewers: eugenis

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D66697

llvm-svn: 369980

msan, codegen, instcombine: Keep more lifetime markers used for msan

Reviewers: eugenis

Subscribers: hiraditya, cfe-commits, #sanitizers, llvm-commits

Tags: #clang, #sanitizers, #llvm

Differentia

msan, codegen, instcombine: Keep more lifetime markers used for msan

Reviewers: eugenis

Subscribers: hiraditya, cfe-commits, #sanitizers, llvm-commits

Tags: #clang, #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D66695

llvm-svn: 369979

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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

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

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[BPF] annotate DIType metadata for builtin preseve_array_access_index()

Previously, debuginfo types are annotated to
IR builtin preserve_struct_access_index() and
preserve_union_access_index(), but

[BPF] annotate DIType metadata for builtin preseve_array_access_index()

Previously, debuginfo types are annotated to
IR builtin preserve_struct_access_index() and
preserve_union_access_index(), but not
preserve_array_access_index(). The debug info
is useful to identify the root type name which
later will be used for type comparison.

For user access without explicit type conversions,
the previous scheme works as we can ignore intermediate
compiler generated type conversions (e.g., from union types to
union members) and still generate correct access index string.

The issue comes with user explicit type conversions, e.g.,
converting an array to a structure like below:
struct t { int a; char b[40]; };
struct p { int c; int d; };
struct t *var = ...;
... __builtin_preserve_access_index(&(((struct p *)&(var->b[0]))->d)) ...
Although BPF backend can derive the type of &(var->b[0]),
explicit type annotation make checking more consistent
and less error prone.

Another benefit is for multiple dimension array handling.
For example,
struct p { int c; int d; } g[8][9][10];
... __builtin_preserve_access_index(&g[2][3][4].d) ...
It would be possible to calculate the number of "struct p"'s
before accessing its member "d" if array debug info is
available as it contains each dimension range.

This patch enables to annotate IR builtin preserve_array_access_index()
with proper debuginfo type. The unit test case and language reference
is updated as well.

Signed-off-by: Yonghong Song <[email protected]>

Differential Revision: https://reviews.llvm.org/D65664

llvm-svn: 367724

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fix unnamed fiefield issue and add tests for __builtin_preserve_access_index intrinsic

The original commit is r366076. It is temporarily reverted (r366155)
due to test failure. This resubmit makes t

fix unnamed fiefield issue and add tests for __builtin_preserve_access_index intrinsic

The original commit is r366076. It is temporarily reverted (r366155)
due to test failure. This resubmit makes test more robust by accepting
regex instead of hardcoded names/references in several places.

This is a followup patch for https://reviews.llvm.org/D61809.
Handle unnamed bitfield properly and add more test cases.

Fixed the unnamed bitfield issue. The unnamed bitfield is ignored
by debug info, so we need to ignore such a struct/union member
when we try to get the member index in the debug info.

D61809 contains two test cases but not enough as it does
not checking generated IRs in the fine grain level, and also
it does not have semantics checking tests.
This patch added unit tests for both code gen and semantics checking for
the new intrinsic.

Signed-off-by: Yonghong Song <[email protected]>
llvm-svn: 366231

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