Currently, ubsan emits overflow checks for arithmetic that is known to
be safe at compile-time, e.g:

  1 + 1 => CheckedAdd(1, 1)

This leads to breakage when using the __builtin_prefetch intrinsic. LLVM
expects the arguments to @llvm.prefetch to be constant integers, and
when ubsan inserts unnecessary checks on the operands to the intrinsic,
this contract is broken, leading to verifier failures (see PR32874).

Instead of special-casing __builtin_prefetch for ubsan, this patch fixes
the underlying problem, i.e that clang currently emits unnecessary
overflow checks.

Testing: I ran the check-clang and check-ubsan targets with a stage2,
ubsan-enabled build of clang. I added a regression test for PR32874, and
some extra checking to make sure we don't regress runtime checking for
unsafe arithmetic. The existing ubsan-promoted-arithmetic.cpp test also
provides coverage for this change.

llvm-svn: 301988

llvm-svn: 301987

Previously we had knowledge of how to serialize and deserialize
a string table inside of DebugInfo/PDB, but the string table
that it serializes contains a piece that is actually considered
CodeView and can appear outside of a PDB.  We already have logic
in llvm-readobj and MCCodeView to read and write this format,
so it doesn't make sense to duplicate the logic in DebugInfoPDB
as well.

This patch makes codeview::StringTable (for writing) and
codeview::StringTableRef (for reading), updates DebugInfoPDB
to use these classes for its own writing, and updates llvm-readobj
to additionally use StringTableRef for reading.

It's a bit more difficult to get MCCodeView to use this for
writing, but it's a logical next step.

llvm-svn: 301986

llvm-svn: 301985

This patch verifies the .debug_line:
- verify all addresses in a line table sequence have ascending addresses
- verify that all line table file indexes are valid

Unit tests added for both cases.

Differential Revision: https://reviews.llvm.org/D32765

llvm-svn: 301984

When we replaced the multiplicand the destination node might already exist.
When that happens the original gets CSEd and deleted. However, it's actually
used as the offset so nonsense is produced.

Should fix PR32726.

llvm-svn: 301983

llvm-svn: 301982

This time, I fixed, built, and tested clang.

This reverts r301712.

llvm-svn: 301981

Remove "_NC" suffix and semantics from TLSDESC_LD{64,32}_LO12 and
  TLSDESC_ADD_LO12 relocations
Rearrange ordering in AArch64.def to follow relocation encoding
Fix name:
  R_AARCH64_P32_LD64_GOT_LO12_NC => R_AARCH64_P32_LD32_GOT_LO12_NC
Add support for several "TLS", "TLSGD", and "TLSLD" relocations for
  ILP32
Fix return values from isNonILP32reloc
Add implementations for
  R_AARCH64_ADR_PREL_PG_HI21_NC, R_AARCH64_P32_LD32_GOT_LO12_NC,
  R_AARCH64_P32_TLSIE_LD32_GOTTPREL_LO12_NC,
  R_AARCH64_P32_TLSDESC_LD32_LO12, R_AARCH64_LD64_GOT_LO12_NC,
  *TLSLD_LDST128_DTPREL_LO12, *TLSLD_LDST128_DTPREL_LO12_NC,
  *TLSLE_LDST128_TPREL_LO12, *TLSLE_LDST128_TPREL_LO12_NC
Modify error messages to give name of equivalent relocation in the
  ABI not being used, along with better checking for non-existent
  requested relocations.
Added assembler support for "pg_hi21_nc"
Relocation definitions added without implementations:
  R_AARCH64_P32_TLSDESC_ADR_PREL21, R_AARCH64_P32_TLSGD_ADR_PREL21,
  R_AARCH64_P32_TLSGD_ADD_LO12_NC, R_AARCH64_P32_TLSLD_ADR_PREL21, 
  R_AARCH64_P32_TLSLD_ADR_PAGE21, R_AARCH64_P32_TLSLD_ADD_LO12_NC,
  R_AARCH64_P32_TLSLD_LD_PREL19, R_AARCH64_P32_TLSDESC_LD_PREL19,
  R_AARCH64_P32_TLSGD_ADR_PAGE21, R_AARCH64_P32_TLS_DTPREL,
  R_AARCH64_P32_TLS_DTPMOD, R_AARCH64_P32_TLS_TPREL,
  R_AARCH64_P32_TLSDESC
Fix encoding:
  R_AARCH64_P32_TLSDESC_ADR_PAGE21

Reviewers: Peter Smith

Patch by: Joel Jones (jjones@cavium.com)

Differential Revision: https://reviews.llvm.org/D32072

llvm-svn: 301980

llvm-svn: 301979

The directory and file tables now have form-based content descriptors.
Parse these and extract the per-directory/file records based on the
descriptors.  For now we support only DW_FORM_string (inline) for the
path names; follow-up work will add support for indirect forms (i.e.,
DW_FORM_strp, strx<N>, and line_strp).

Differential Revision: http://reviews.llvm.org/D32713

llvm-svn: 301978

Turns out this wasn't NFC-ish at all because there's a bug processing shuffles
that change the size of their input vectors (that case always seems to trip us
up). 

This should fix PR32872 while we investigate how it failed and reduce a testcase:
https://bugs.llvm.org/show_bug.cgi?id=32872
 

llvm-svn: 301977

llvm-svn: 301976

llvm-svn: 301975

llvm-svn: 301974

- this is added just for completeness sake (though the general case should be represented by the test added in the revision to that patch:  https://reviews.llvm.org/rL301972 )

llvm-svn: 301973

Fix PR32831 (Try Again): 'this' capture while instantiating generic lambda call operator specialization

When computing the appropriate cv-qualifiers for the 'this' capture, we have to examine each enclosing lambda - but when using the FunctionScopeInfo stack we have to ensure that the lambda below (outer) is the decl-context of the closure-class of the current lambda.

https://bugs.llvm.org/show_bug.cgi?id=32831

This patch was initially committed here: https://reviews.llvm.org/rL301735
Then reverted here: https://reviews.llvm.org/rL301916

The issue with the original patch was a failure to check that the closure type has been created within the LambdaScopeInfo before querying its DeclContext - instead of just assuming it has (silly!).  A reduced example such as this highlights the problem:
  struct X {
     int data;
     auto foo() { return [] { return [] -> decltype(data) { return 0; }; }; }
  };

When 'data' within decltype(data) tries to determine the type of 'this', none of the LambdaScopeInfo's have their closure types created at that point.

 

llvm-svn: 301972

LTO and other fancy linking previously led to DWARF that contained invalid references. We already validate that CU relative references fall into the CU, and the DW_FORM_ref_addr references fall inside the .debug_info section, but we didn't validate that the references pointed to correct DIE offsets. This new verification will ensure that all references refer to actual DIEs and not an offset in between.

This caught a bug in DWARFUnit::getDIEForOffset() where if you gave it any offset, it would match the DIE that mathes the offset _or_ the next DIE. This has been fixed.

Differential Revision: https://reviews.llvm.org/D32722

llvm-svn: 301971

llvm-svn: 301970

This reverts commit r301964. It broke the build.

llvm-svn: 301969

Combine the logic doing the ms_abi/sysv_abi checks into one function so
that each check and its logical opposite are near each other. Now we
don't need two Sema entry points for MS va_start and regular va_start.

Refactor the code that checks if the va_start caller is a function,
block, or obj-c method. We do this in three places, and they are all
buggy for variadic lambdas (PR32737). After this change, I have one
place to apply the functional fix.

NFC

llvm-svn: 301968

llvm-svn: 301967

This patch marks a few ASan tests as unsupported on iOS. These are mostly tests that use files or paths that are invalid/inaccessible on iOS or the simulator. We currently don't have a good way of propagating/copying secondary files that individual tests need. The same problem exists on Android, so I'm just marking the tests as UNSUPPORTED now.

Differential Revision: https://reviews.llvm.org/D32632

llvm-svn: 301966

Differential Revision: https://reviews.llvm.org/D32633

llvm-svn: 301965

llvm-svn: 301964

handling of constexprs with unknown bounds.

This triggers a corner case of the language where it's not yet clear
whether this should be an error:

  struct A {
    static void *const a[];
    static void *const b[];
  };
  constexpr void *A::a[] = {&b[0]};
  constexpr void *A::b[] = {&a[0]};

When discovering the initializer for A::a, the bounds of A::b aren't known yet.
It is unclear whether warning about errors should be deferred until the end of
the translation unit, possibly resolving errors that can be resolved. In
practice, the compiler can know the bounds of all arrays in this example.

Credits for reproducers and explanation go to Richard Smith. Richard, please
add more info in case my explanation is wrong.

llvm-svn: 301963

I doubt anyone actually uses it, and I'm not even entirely convinced it exists
myself; but it is our default for "clang -arch armv6". Functionally, if it does
exist it's identical to the arm1176jz-f from LLVM's point of view (the
difference is apparently in the "Security Extensions").

llvm-svn: 301962

On AMDGPU if an SGPR is spilled to a VGPR, the frame index
is deleted. If there were any CSR SGPRs, this woudl
assert when setting the offset.

llvm-svn: 301961

This reverts commit r300295.

It's no longer true, print_stacktrace=1 is supported on Darwin/Windows
as of r301839.

llvm-svn: 301960

This is a follow up to the previous
inline cost patch for quicker filtering.

llvm-svn: 301959

LDS use in leaf functions not currently handled.

llvm-svn: 301958

Patch by Colin LeMahieu.

llvm-svn: 301957

Patch by Colin LeMahieu.

llvm-svn: 301956

Patch by Sid Manning.

llvm-svn: 301955

The compiler was generating code that ends up ignoring a multiple
latency dependence between two instructions by scheduling the
intructions in back-to-back packets. 

The packetizer needs to end a packet if the latency of the current
current insruction and the source in the previous packet is
greater than 1 cycle. This case occurs when there is still room in
the current packet, but scheduling the instruction causes a stall.
Instead, the packetizer should start a new packet. Also, if the
current packet already contains a stall, then it is okay to add
another instruction to the packet that also causes a stall. This
occurs when there are no instructions that can be scheduled in
between the producer and consumer instructions.

This patch changes the latency for loads to 2 cycles from 3 cycles.
This change refects that a load only needs to be separated by
one extra packet to eliminate the stall.

Patch by Ikhlas Ajbar.

llvm-svn: 301954

llvm-svn: 301953

Patch by Colin LeMahieu.

llvm-svn: 301952

Patch by Colin LeMahieu.

llvm-svn: 301951

Just let TTI's cost do this instead of arbitrarily restricting
this.

llvm-svn: 301950

Patch by Colin LeMahieu.

llvm-svn: 301949