This reapplies 87403600, which was reverted in bbddadd4 due to buildbot
errors.

This version checks that a JIT instance can be safely constructed, skipping
tests if it can not be. To enable this it introduces new C API to retrieve and
set the target triple for a JITTargetMachineBuilder.

This revision takes the forward value propagation engine in SCCP and refactors it into a more generalized forward dataflow analysis framework. This framework allows for propagating information about values across the various control flow constructs in MLIR, and removes the need for users to reinvent the traversal (often not as completely). There are a few aspects of the traversal, that were conservative for SCCP, that should be relaxed to support the needs of different value analyses. To keep this revision simple, these conservative behaviors will be left in (Note that this won't produce an incorrect result, but may produce more conservative results than necessary in certain edge cases. e.g. region entry arguments for non-region branch interface operations). The framework also only focuses on computing lattices for values, given the SCCP origins, but this is something to relax as needed in the future.

Given that this logic is already in SCCP, a majority of this commit is NFC. The more interesting parts are the interface glue that clients interact with.

Differential Revision: https://reviews.llvm.org/D100915

We request no intersections between AMX instructions and their shapes'
def when we insert ldtilecfg. However, this is not always ture resulting
from not only users don't follow AMX API model, but also optimizations.

This patch adds a mechanism that tries to hoist AMX shapes' def as well.
It only hoists shapes inside a BB, we can improve it for cases across
BBs in future. Currently, it only hoists shapes of which all sources' def
above the first AMX instruction. We can improve for the case that only
source that moves an immediate value to a register below AMX instruction.

Reviewed By: xiangzhangllvm

Differential Revision: https://reviews.llvm.org/D101067

This reverts commit 15be0c41.

The previous comment was pretty obscure.

The new "encoding" field in tensor types so far had no meaning. This revision introduces:

1. an encoding attribute interface in IR: for verification between tensors and encodings in general
2. an attribute in Tensor dialect; #tensor.sparse<dict> + concrete sparse tensors API

Active discussion:
https://llvm.discourse.group/t/rfc-introduce-a-sparse-tensor-type-to-core-mlir/2944/

Reviewed By: silvas, penpornk, bixia

Differential Revision: https://reviews.llvm.org/D101008

For an example like below,
    extern int do_work(int);
    long bpf_helper(void *callback_fn);
    long prog() {
        return bpf_helper(&do_work);
    }

The final generated codes look like:
    r1 = do_work ll
    call bpf_helper
    exit
where we have debuginfo for do_work() extern function:
    !17 = !DISubprogram(name: "do_work", ...)

This patch implemented to add additional checking
in processing LD_imm64 operands for possible function pointers
so BTF for bpf function do_work() can be properly generated.
The original llvm function name processReloc() is renamed to
processGlobalValue() to better reflect what the function is doing.

Differential Revision: https://reviews.llvm.org/D100568

The ModulePassManager should already have taken care of all analysis
invalidation. Without this change, upcoming changes will cause more
invalidation than necessary.

Reviewed By: mtrofin

Differential Revision: https://reviews.llvm.org/D101320

Add two canoncalizations for scf.if.
  1) A canonicalization that allows users of a condition within an if to assume the condition
     is true if in the true region, etc.
  2) A canonicalization that removes yielded statements that are equivalent to the condition
     or its negation

Differential Revision: https://reviews.llvm.org/D101012

LLVM does not have valid assembly backends for atomicrmw on local memory. However, as this memory is thread local, we should be able to lower this to the relevant load/store.

Differential Revision: https://reviews.llvm.org/D98650

The VFS is null when it's invalid so return early in collectVFSFromYAML.

Commit e3d8ee35 ("reland "[DebugInfo] Support to emit debugInfo
for extern variables"") added support to emit debugInfo for
extern variables if requested by the target. Currently, only
BPF target enables this feature by default.

As BPF ecosystem grows, callback function started to get
support, e.g., recently bpf_for_each_map_elem() is introduced
(https://lwn.net/Articles/846504/) with a callback function as an
argument. In the future we may have something like below as
a demonstration of use case :
    extern int do_work(int);
    long bpf_helper(void *callback_fn, void *callback_ctx, ...);
    long prog_main() {
        struct { ... } ctx = { ... };
        return bpf_helper(&do_work, &ctx, ...);
    }
Basically bpf helper may have a callback function and the
callback function is defined in another file or in the kernel.
In this case, we would like to know the debuginfo types for
do_work(), so the verifier can proper verify the safety of
bpf_helper() call.

For the following example,
    extern int do_work(int);
    long bpf_helper(void *callback_fn);
    long prog() {
        return bpf_helper(&do_work);
    }

Currently, there is no debuginfo generated for extern function do_work().
In the IR, we have,
    ...
    define dso_local i64 @prog() local_unnamed_addr #0 !dbg !7 {
    entry:
      %call = tail call i64 @bpf_helper(i8* bitcast (i32 (i32)* @do_work to i8*)) #2, !dbg !11
      ret i64 %call, !dbg !12
    }
    ...
    declare dso_local i32 @do_work(i32) #1
    ...

This patch added support for the above callback function use case, and
the generated IR looks like below:
    ...
    declare !dbg !17 dso_local i32 @do_work(i32) #1
    ...
    !17 = !DISubprogram(name: "do_work", scope: !1, file: !1, line: 1, type: !18, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized, retainedNodes: !2)
    !18 = !DISubroutineType(types: !19)
    !19 = !{!20, !20}
    !20 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)

The TargetInfo.allowDebugInfoForExternalVar is renamed to
TargetInfo.allowDebugInfoForExternalRef as now it guards
both extern variable and extern function debuginfo generation.

Differential Revision: https://reviews.llvm.org/D100567

As a follow-up to D95982, this patch continues unblocking optimizations that are blocked by pseudu probe instrumention.

The optimizations unblocked are:
		- In-block load propagation.
		- In-block dead store elimination
		- Memory copy optimization that turns stores to consecutive memories into a memset.

These optimizations are local to a block, so they shouldn't affect the profile quality.

Reviewed By: wmi

Differential Revision: https://reviews.llvm.org/D100075

In LLVM_ENABLE_STATS=0 builds, `llvm::Statistic` maps to `llvm::NoopStatistic`
but has 3 mostly unused pointers. GlobalOpt considers that the pointers can
potentially retain allocated objects, so GlobalOpt cannot optimize out the
`NoopStatistic` variables (see D69428 for more context), wasting 23KiB for stage
2 clang.

This patch makes `NoopStatistic` empty and thus reclaims the wasted space.  The
clang size is even smaller than applying D69428 (slightly smaller in both .bss and
.text).
```
# This means the D69428 optimization on clang is mostly nullified by this patch.
HEAD+D69428: size(.bss) = 0x0725a8
HEAD+D101211: size(.bss) = 0x072238

# bloaty - HEAD+D69428 vs HEAD+D101211
# With D101211, we also save a lot of string table space (.rodata).
    FILE SIZE        VM SIZE
 --------------  --------------
  -0.0%     -32  -0.0%     -24    .eh_frame
  -0.0%    -336  [ = ]       0    .symtab
  -0.0%    -360  [ = ]       0    .strtab
  [ = ]       0  -0.2%    -880    .bss
  -0.0% -2.11Ki  -0.0% -2.11Ki    .rodata
  -0.0% -2.89Ki  -0.0% -2.89Ki    .text
  -0.0% -5.71Ki  -0.0% -5.88Ki    TOTAL
```

Note: LoopFuse is a disabled pass. For now this patch adds
`#if LLVM_ENABLE_STATS` so `OptimizationRemarkMissed` is skipped in
LLVM_ENABLE_STATS==0 builds.  If these `OptimizationRemarkMissed` are useful in
LLVM_ENABLE_STATS==0 builds, we can replace `llvm::Statistic` with
`llvm::TrackingStatistic`, or use a different abstraction to keep track of the strings.

Similarly, skip the code in `mlir/lib/Pass/PassStatistics.cpp` which
calls `getName`/`getDesc`/`getValue`.

Reviewed By: lattner

Differential Revision: https://reviews.llvm.org/D101211

This reverts commit fede99d3.

LLVM does not have valid assembly backends for atomicrmw on local memory. However, as this memory is thread local, we should be able to lower this to the relevant load/store.

Differential Revision: https://reviews.llvm.org/D98650

The order regressed after D94202: after `a b`, when adding `a c`, we may reorder
`a` to the right of `b`, causing the final order to be `b a c`.

Reduces the amount of vector ALU operations and reduces vector
register pressure.

This reverts commit b5403117
because it breaks MLIR build:

https://buildkite.com/mlir/mlir-core/builds/13299#ad0f8901-dfa4-43cf-81b8-7940e2c6c15b

The value observed for the `mtim.tv_nsec` member is erroneous in some
AIX environments. Avoid using this member by forcing
`HAVE_STRUCT_STAT_ST_MTIM_TV_NSEC` to `0`.

This resolves "mtime changed" errors such as the one
http://lab.llvm.org:8014/#/builders/126/builds/330/steps/5/logs/FAIL__Clang__test_c
has.

Reviewed By: daltenty, jsji

Differential Revision: https://reviews.llvm.org/D101323

When replacing a conditional branch by an unconditional one because the targets are identical, transfer the metadata to the new branch instruction.

Reviewed By: lebedev.ri

Differential Revision: https://reviews.llvm.org/D101226

This reverts commit 0ce723cb.

D76519 was not quite NFC. If we see a CFISection::Debug function before a
CFISection::EH one (-fexceptions -fno-asynchronous-unwind-tables), we may
incorrectly pick CFISection::Debug and emit a `.cfi_sections .debug_frame`.
We should use .eh_frame instead.

This scenario is untested.

This reverts commit 87403600.

This commit caused failures on some builders (see e.g.
https://lab.llvm.org/buildbot/#/builders/5/builds/7071). Reverting while I
investigate.

These are intended to mimic warnings available in gcc.

-Wunused-but-set-variable is triggered in the case of a variable which
appears on the LHS of an assignment but not otherwise used.

For instance:

  void f() {
    int x;
    x = 0;
  }

-Wunused-but-set-parameter works similarly, but for function parameters
instead of variables.

In C++, they are triggered only for scalar types; otherwise, they are
triggered for all types. This is gcc's behavior.

-Wunused-but-set-parameter is controlled by -Wextra, while
-Wunused-but-set-variable is controlled by -Wunused. This is slightly
different from gcc's behavior, but seems most consistent with clang's
behavior for -Wunused-parameter and -Wunused-variable.

Reviewed By: aeubanks

Differential Revision: https://reviews.llvm.org/D100581

Based on D100160.

Reviewed By: cjdb, ldionne, Quuxplusone, #libc, miscco

Differential Revision: https://reviews.llvm.org/D100587

This reverts commit 6cc62043.

This caused a test failure on a M1 mac CI job (https://reviews.llvm.org/D100807#2718006),
I will recommit this with a fix.

the compilation time and there is no case for which we see any improvement in
performance. This patch removes this pass and its associated test cases from
the tree.

Differential Revision: https://reviews.llvm.org/D101313

Change-Id: I0599169a7609c19a887f8d847a71e664030cc141

This patch adds the missing implementation for
TargetTransformInfo::hasActiveVectorLength() without which using
hasActiveVectorLength() causes linker error.

Patch by Vineet Kumar!

Differential Revision: https://reviews.llvm.org/D100941

Support leak sanitizer in libcxx.

Simple addition for leak checking when running the libcxx testsuite.

Differential Revision: https://reviews.llvm.org/D100775

Don't fail the shared_ptr test if libc++ has insufficient debug info.

This addresses https://bugs.llvm.org/show_bug.cgi?id=48937

Differential Revision: https://reviews.llvm.org/D100610

Patch by Mats Larsen. Thanks Mats!

Reviewed By: lhames

Differential Revision: https://reviews.llvm.org/D100506

Adds support for creating custom MaterializationUnits in the C API with the new
LLVMOrcCreateCustomMaterializationUnit function.

Modifies ownership rules for LLVMOrcAbsoluteSymbols to make it consistent with
LLVMOrcCreateCustomMaterializationUnit. This is an ABI breaking change for any
clients of the LLVMOrcAbsoluteSymbols API.

Adds LLVMOrcLLJITGetObjLinkingLayer and LLVMOrcObjectLayerEmit functions to
allow clients to get a reference to an LLJIT instance's linking layer, then
emit an object file using it. This can be used to support construction of
custom materialization units in the common case where those units will
generate an object file that needs to be emitted to complete the
materialization.

Rename JITTargetSymbolFlags to JITSymbolTargetFlags. This matches the convention
used for JITSymbolGenericFlags.

In LLVM_ENABLE_STATS=0 builds, `llvm::Statistic` maps to `llvm::NoopStatistic`
but has 3 unused pointers. GlobalOpt considers that the pointers can potentially
retain allocated objects, so GlobalOpt cannot optimize out the `NoopStatistic`
variables (see D69428 for more context), wasting 23KiB for stage 2 clang.

This patch makes `NoopStatistic` empty and thus reclaims the wasted space.  The
clang size is even smaller than applying D69428 (slightly smaller in both .bss and
.text).
```
# This means the D69428 optimization on clang is mostly nullified by this patch.
HEAD+D69428: size(.bss) = 0x0725a8
HEAD+D101211: size(.bss) = 0x072238

# bloaty - HEAD+D69428 vs HEAD+D101211
# With D101211, we also save a lot of string table space (.rodata).
    FILE SIZE        VM SIZE
 --------------  --------------
  -0.0%     -32  -0.0%     -24    .eh_frame
  -0.0%    -336  [ = ]       0    .symtab
  -0.0%    -360  [ = ]       0    .strtab
  [ = ]       0  -0.2%    -880    .bss
  -0.0% -2.11Ki  -0.0% -2.11Ki    .rodata
  -0.0% -2.89Ki  -0.0% -2.89Ki    .text
  -0.0% -5.71Ki  -0.0% -5.88Ki    TOTAL
```

Note: LoopFuse is a disabled pass. This patch adds `#if LLVM_ENABLE_STATS` so
`OptimizationRemarkMissed` is skipped in LLVM_ENABLE_STATS==0 builds.  If these
`OptimizationRemarkMissed` are useful and not noisy, we can replace
`llvm::Statistic` with `llvm::TrackingStatistic` in the future.

Reviewed By: lattner

Differential Revision: https://reviews.llvm.org/D101211

This modifies my previous patch to push the strided load formation
to isel. This gives us opportunity to fold the splat into a .vx
operation first. Using a scalar register and a .vx operation reduces
vector register pressure which can be important for larger LMULs.

If we can't fold the splat into a .vx operation, then it can make
sense to use a strided load to free up the vector arithmetic
ALU to do actual arithmetic rather than tying it up with vmv.v.x.

Reviewed By: khchen

Differential Revision: https://reviews.llvm.org/D101138