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@tommymcm tommymcm commented Aug 7, 2025

We were missing argument handling for -fclangir-idiom-recognizer on its own, and were not propagating -fclangir-lib-opt for the clang toolchain.

Lancern and others added 30 commits April 9, 2025 15:19
…1487)

This PR resolves an assertion failure in
`CIRGenTypes::isFuncParamTypeConvertible`, which is involved when trying
to emit a vtable entry to a virtual function whose type includes a
pointer-to-member-function.
…lvm#1431)

Implements `::verify` for operations cir.atomic.xchg and
cir.atomic.cmp_xchg

I believe the existing regression tests don't get to the CIR level type
check failure and I was not able to implement a case that does.

Most attempts of reproducing cir.atomic.xchg type check failure were
along the lines of:
```
int a;
long long b,c;
__atomic_exchange(&a, &b, &c, memory_order_seq_cst);
```

And they seem to never trigger the failure on `::verify` because they
fail earlier in function parameter checking:
```
exmp.cpp:7:27: error: cannot initialize a parameter of type 'int *' with an rvalue of type 'long long *'
    7 |     __atomic_exchange(&a, &b, &c, memory_order_seq_cst);
      |                           ^~
```

Closes llvm#1378 .
This PR adds a new boolean flag to the `cir.load` and the `cir.store`
operation that distinguishes nontemporal loads and stores. Besides, this
PR also adds support for the `__builtin_nontemporal_load` and the
`__builtin_nontemporal_store` intrinsic function.
This PR adds a new boolean flag to the `cir.load` and the `cir.store`
operation that distinguishes nontemporal loads and stores. Besides, this
PR also adds support for the `__builtin_nontemporal_load` and the
`__builtin_nontemporal_store` intrinsic function.
This PR adds an insertion guard for the try body scope for try-catch.
Currently, the following code snippet fails during CodeGen:

```
void foo() {
  int r = 1;
  try {
    ++r;
    return;
  } catch (...) {
  }
}
```

The insertion point doesn't get reset properly and the cleanup is being
ran for a wrong/deleted block causing a segmentation fault. I also added
a test.
The comments suggested that we should use TableGen to generate the
recognizing functions. However, I think templates might be more suitable
for generating them -- and I can't find any existing TableGen backends
that let us generate arbitrary functions.

My choice of design is to offer a template to match standard library
functions:
```cpp
// matches std::find with 3 arguments, and raise it into StdFindOp
StdRecognizer<3, StdFindOp, StdFuncsID::Find>
```
I have to use a TableGen'd enum to map names to IDs, as we can't pass
string literals to template arguments easily in C++17.

This also constraints design of future `StdXXXOp`s: they must take
operands the same way of StdFindOp, where the first one is the original
function, and the rest are function arguments.

I'm not sure if this approach is the best way. Please tell me if you
have concerns or any alternative ways.
…was set explicitly (llvm#1482)

This is backported from a change made in
llvm/llvm-project#131181

---------

Co-authored-by: Morris Hafner <[email protected]>
…R attribute. (llvm#1467)

Started decorating CUDA shadow variables with the shadow_name CIR
attribute which will be used for registering the globals.
… target was set explicitly" (llvm#1509)

Reverts llvm#1482

@mmha this is crashing on macos on asserts build:
```
FAIL: Clang :: CIR/Tools/cir-translate/warn-default-triple.cir (472 of 552)
******************** TEST 'Clang :: CIR/Tools/cir-translate/warn-default-triple.cir' FAILED ********************
Exit Code: 134

Command Output (stdout):
--
Assertion failed: (!DataLayoutString.empty() && "Uninitialized DataLayout!"), function getDataLayoutString, file TargetInfo.h, line 1282.
```

Perhaps besides picking a default you maybe need to do some missing
datalayout init?
…lementwise_acos (llvm#1507)

Closes: llvm#1374

Replaces LLVMIntrinsicCallOp with ACosOp in __builtin_elementwise_acos.
Sub-issue of llvm#1192. Adds
CIR_ASinOp and support for __builtin_elementwise_asin.
This un-xfails the 6 files in llvm#1497 related to variadic calls.
Sub-issue of llvm#1192. Adds
CIR_ATanOp and support for __builtin_elementwise_atan.
Part of llvm#258 .

1. Added `AddressPointAttr`
2. Change all occurrences of `VTableAddrPointOp` into using the
attribute
3. Update tests

---------

Co-authored-by: Sirui Mu <[email protected]>
Co-authored-by: Morris Hafner <[email protected]>
Co-authored-by: Morris Hafner <[email protected]>
Co-authored-by: Sharp-Edged <[email protected]>
Co-authored-by: Amr Hesham <[email protected]>
Co-authored-by: Bruno Cardoso Lopes <[email protected]>
Co-authored-by: Letu Ren <[email protected]>
Clang relies on `llvm::Intrinsic::getOrInsertDeclaration` to handle
functions marked as `ClangBuiltin` in TableGen. That function receives a
`CodeGenModule*` so CIR can't use that. We need to re-implement parts of
it.
Closes llvm#1367

---------

Co-authored-by: Sirui Mu <[email protected]>
Co-authored-by: Amr Hesham <[email protected]>
Co-authored-by: Chibuoyim (Wilson) Ogbonna <[email protected]>
Co-authored-by: Yue Huang <[email protected]>
Co-authored-by: Morris Hafner <[email protected]>
Co-authored-by: Morris Hafner <[email protected]>
Co-authored-by: Sharp-Edged <[email protected]>
Co-authored-by: Bruno Cardoso Lopes <[email protected]>
Co-authored-by: Letu Ren <[email protected]>
andykaylor and others added 19 commits July 24, 2025 09:24
The LoweringPrepare pass was generating the wrong condition for loops
when lowering the ArrayCtor op, causing only one element in an array of
objects to be constructed. This fixes that problem.
Backporting passing enum kind directly to complex cast helpers
…ent (llvm#1748)

## Overview
Currently, getting the pointer to an element of an array requires a
pointer decay and a (possible) pointer stride. A similar pattern for
records has been eliminated with the `cir.get_member` operation. This PR
provides a similar level of abstraction for arrays with the
`get_element` operation.
`get_element` replaces the above pattern with a single operation, which
takes a pointer to an array and an index, and produces a pointer to the
element at that index.
There are many places in CIR analysis and lowering where the
`ptr_stride(array_to_ptrdecay(x), i)` pattern is handled as a special
case. By subsuming the special case pattern with an explicit operation,
we make these analyses and lowering more robust.

## Changes
Adds the `cir.get_element` operation.
Extends CIRGen to emit `cir.get_element` for array subscript
expressions.
Updated LifetimeCheck to handle `get_element` operation, subsuming
special case analysis of `cir.ptr_stride` operation (did not remove the
special case).
Extends CIR-to-LLVM lowering to lower `cir.get_element` to
`llvm.getelementptr`
Extends CIR-to-MLIR lowering to lower `cir.get_element` to `memref`
operations, matching existing special case `cir.ptr_stride` lowering.

## Additional Notes
Currently, 47.6% of `cir.ptr_stride` operations in the llvm-test-suite
(SingleSource and MultiSource) can be replaced by `cir.get_element`
operations.

### Operator Breakdown (current)
name | count | %
-- | -- | --
cir.load | 825221 | 22.27%
cir.br | 429822 | 11.60%
cir.const | 380381 | 10.26%
cir.cast | 325646 | 8.79%
cir.store | 309586 | 8.35%
cir.get_member | 226895 | 6.12%
cir.get_global | 186851 | 5.04%
cir.ptr_stride | 158094 | 4.27%
cir.call | 144522 | 3.90%
cir.binop | 141142 | 3.81%
cir.alloca | 134346 | 3.63%
cir.brcond | 112864 | 3.05%
cir.cmp | 83532 | 2.25%

### Operator Breakdown (with `get_element`)
name | count | %
-- | -- | --
cir.load | 825221 | 22.74%
cir.br | 429822 | 11.84%
cir.const | 380381 | 10.48%
cir.store | 309586 | 8.53%
cir.cast | 248645 | 6.85%
cir.get_member | 226895 | 6.25%
cir.get_global | 186851 | 5.15%
cir.call | 144522 | 3.98%
cir.binop | 141142 | 3.89%
cir.alloca | 134346 | 3.70%
cir.brcond | 112864 | 3.11%
cir.cmp | 83532 | 2.30%
cir.ptr_stride | 81093 | 2.23%
cir.get_elem | 77001 | 2.12%

---------

Co-authored-by: Andy Kaylor <[email protected]>
Co-authored-by: Henrich Lauko <[email protected]>
Implemented `noexcept` expression handling in CIR generation. 
Added a `noexcept.cpp` test based on cppreference. There was no OG test to base it off of, so I used the example code from [cppreference](https://en.cppreference.com/w/cpp/language/noexcept.html).
I think this one is self-explanatory, so I will not write much 🙂‍

Adding this attribute helps in optimizations like
[llvm#1653](llvm#1653), and using the
attribute it's easy to create operations like
`cir.std.vector.ctor`/`cir.std.vector.dtor` by just modifying
`IdiomRecognizer` a bit. I believe it will also be useful for future
optimizations. Finally, I updated quite a number of tests so they now
reflect this attribute.

Please, let me know if you see any issues.
Implemented opportunistic vtable emission, which marks vtables as
`available_externally` to enable inlining if optimizations are enabled.
Added `GlobalOp` verifier support `available_externally` linkage type,
all cases are covered now, so I removed the `default` case.
Added the `vtable-available-externally` CIRGen test.
Fix lowering Complex to Complex cast, backported from
llvm/llvm-project#149717
…r` (llvm#1753)

Implemented CIR code generation for `CXXPseudoDestructorExpr`. 
Added a pseudo destructor test to `CIR/CodeGen/dtors.cpp`.
…trdecay` to `get_element` when possible (llvm#1761)

Extended the `CIRCanonicalizePass` with new rewrite rules: 
- Rewrite `ptr_stride (cast array_to_ptrdecay %base), %index` to
`get_element %base[%index]`
- Rewrite `ptr_stride (get_element %base[%index]), %stride` to
`get_element %base[%index + %stride]`
- Rewrite `cast array_to_ptrdecay %base, ptr<T>` to `get_element
%base[0], ptr<T>` if it is only used by `load %ptr : T`, `store %val :
T, %ptr`, or `get_member %ptr[field] : ptr<T> -> U`

Updated CodeGen tests, and extended CIR-to-CIR test.

---------

Co-authored-by: Henrich Lauko <[email protected]>
)

`cir::PointerType` was not included in the applicability guard for
`cir::VAArg` lowering during `LoweringPrepare`.
Since we don't have generic LLVM `cir::VAArgOp` (see [more
info](llvm#1088 (comment)))
this causes an NYI error during lowering that doesn't need to happen.
To fix this I added the missing `cir::PointerType` to the `isa`. 
There is probably a more comprehensive fix to this if someone is
interested, this check should be removed and let the (possible) error
occur at the actual NYI site.
- Replaces  dyn_cast<cir::ConstantOp>(v.getDefiningOp()) and similar with v.getDefiningOp<cir::ConstantOp>()
- Adds `getValueAttr`, `getIntValue` and `getBoolValue` methods to ConstantOp
…1747)

(Copied from my question on Discord)
 
I’ve been working on the vector to bit-mask related intrinsics for X86.
I’ve been stuck specifically on
`X86::BI__builtin_ia32_cvtb2mask128(_mm256_movepi16_mask`) and its
variations with different vector/mask sizes.

In this case, we perform a vector comparison of `vector<16xi16>` and
bitcast the resulting `vector<16xi1>` directly into a scalar integer
mask (i16).

I’m successfully able to lower to cir:
```
    ...
    %5 = cir.vec.cmp(lt, %3, %4) : !cir.vector<!s16i x 16>, !cir.vector<!cir.int<u, 1> x 16>
    %6 = cir.cast(bitcast, %5 : !cir.vector<!cir.int<u, 1> x 16>), !u16i
    ...
```

There's an issue arises when lowering this to LLVM, the error message
I'm getting is:

```
error: integer width of the output type is smaller or equal to the integer width of the input type
```

By looking at the test cases on the llvm dialect, this is related to the
sext / zext instruction.

This is the cir → llvm dialect lowered for the latter:

```
        ...
    %14 = "llvm.icmp"(%12, %13) <{predicate = 2 : i64}> : (vector<16xi16>, vector<16xi16>) -> vector<16xi1>
    %15 = "llvm.sext"(%14) : (vector<16xi1>) -> vector<16xi1>
    %16 = "llvm.bitcast"(%15) : (vector<16xi1>) -> i16
        ...
```

This is seems to be the cause:

```
 %15 = "llvm.sext"(%14) : (vector<16xi1>) -> vector<16xi1>
 ```
 
 **The fix**: Added a type check: if the result type does not differ from the expected type, we won't insert a sextOp
Implemented `CXXDeleteExpr` for concrete and virtual destructors.
NYI, global delete, i.e., `::delete`.
Added tests for both destructor types.
For these intrinsics there only seems to be one function where the IR
emmited seems to diverge:

for `_mm_load_sbh` loads a single 16-bit bfloat (__bf16) value from
memory into the lowest element of a 128-bit bfloat vector (__m128bh),
leaving the remaining lanes unchanged or filled with a passthrough
value. It is implemented using a masked load with only the first lane
enabled.

[source for intrinsics with similar
behaviour](https://gist.github.com/leopck/86799fee6ceb9649d0ebe32c1c6e5b85)

In the CIR lowering of `_mm_load_sbh`, we are currently emitting the
mask of intrinsic (`llvm.masked.load`) operand as an explicit constant
vector:

``` llvm
<8 x i1> <true, false, false, false, false, false, false, false>
```
whereas OG lowers:
```llvm
<8 x i1> bitcast (<1 x i8> splat (i8 1) to <8 x i1>)
```
I believe both things are semantically equal so:

Is it acceptable for CIR and OG to diverge in this way for masked loads,
or should we aim for parity in how the mask is represented, even if that
reduces readability in CIR?
Implement supporting for CK_LValueToRValueBitCast for ComplexType
@tommymcm tommymcm marked this pull request as draft August 8, 2025 16:26
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tommymcm commented Aug 8, 2025

Adding tests, converted to draft until they're done.

@tommymcm tommymcm marked this pull request as ready for review August 8, 2025 16:30
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tommymcm commented Aug 8, 2025

Tests are all added, ready for review.

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