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WIP support compound literals - #1

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WIP support compound literals#1
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mpirog/n3038

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This is WIP patch with support for storage class for compound literals for C23. (proposal N3038)

The storage class is being accepted as a valid syntax; error is raised on invalid storage class specifiers. What needs to be done is handling the semantics of storage classes (like raising error on taking address of register variable)

mikolaj-pirog pushed a commit that referenced this pull request Feb 5, 2026
…lvm#178069)

Kernel panic is a special case, and there is no signal or exception for
that so we need to rely on special workaround called `dumptid`.
FreeBSDKernel plugin is supposed to find this thread and set it manually
through `SetStopInfo()` in `CalculateStopInfo()` like Mach core plugin
does.

Before (We had to find and select crashed thread list otherwise thread 1
was selected by default):
```
➜ sudo lldb /boot/panic/kernel -c /var/crash/vmcore.last
(lldb) target create "/boot/panic/kernel" --core "/var/crash/vmcore.last"
Core file '/var/crash/vmcore.last' (x86_64) was loaded.
(lldb) bt
* thread #1, name = '(pid 12991) dtrace'
  * frame #0: 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff8015882f780, flags=259) at sched_ule.c:2448:26
    frame #1: 0xffffffff80bd38d2 kernel`mi_switch(flags=259) at kern_synch.c:530:2
    frame llvm#2: 0xffffffff80c29799 kernel`sleepq_switch(wchan=0xfffff8014edff300, pri=0) at subr_sleepqueue.c:608:2
    frame llvm#3: 0xffffffff80c29b76 kernel`sleepq_catch_signals(wchan=0xfffff8014edff300, pri=0) at subr_sleepqueue.c:523:3
    frame llvm#4: 0xffffffff80c29d32 kernel`sleepq_timedwait_sig(wchan=<unavailable>, pri=<unavailable>) at subr_sleepqueue.c:704:11
    frame llvm#5: 0xffffffff80bd2e2d kernel`_sleep(ident=0xfffff8014edff300, lock=0xffffffff81df2880, priority=768, wmesg="uwait", sbt=2573804118162, pr=0, flags=512) at kern_synch.c:215:10
    frame llvm#6: 0xffffffff80be8622 kernel`umtxq_sleep(uq=0xfffff8014edff300, wmesg="uwait", timo=0xfffffe0279cb3d20) at kern_umtx.c:843:11
    frame llvm#7: 0xffffffff80bef87a kernel`do_wait(td=0xfffff8015882f780, addr=<unavailable>, id=0, timeout=0xfffffe0279cb3d90, compat32=1, is_private=1) at kern_umtx.c:1316:12
    frame llvm#8: 0xffffffff80bed264 kernel`__umtx_op_wait_uint_private(td=0xfffff8015882f780, uap=0xfffffe0279cb3dd8, ops=<unavailable>) at kern_umtx.c:3990:10
    frame llvm#9: 0xffffffff80beaabe kernel`sys__umtx_op [inlined] kern__umtx_op(td=<unavailable>, obj=<unavailable>, op=<unavailable>, val=<unavailable>, uaddr1=<unavailable>, uaddr2=<unavailable>, ops=<unavailable>) at kern_umtx.c:4999:10
    frame llvm#10: 0xffffffff80beaa89 kernel`sys__umtx_op(td=<unavailable>, uap=<unavailable>) at kern_umtx.c:5024:10
    frame llvm#11: 0xffffffff81122cd1 kernel`amd64_syscall [inlined] syscallenter(td=0xfffff8015882f780) at subr_syscall.c:165:11
    frame llvm#12: 0xffffffff81122c19 kernel`amd64_syscall(td=0xfffff8015882f780, traced=0) at trap.c:1208:2
    frame llvm#13: 0xffffffff810f1dbb kernel`fast_syscall_common at exception.S:570
```

After:
```
➜ sudo ./build/bin/lldb /boot/panic/kernel -c /var/crash/vmcore.last
(lldb) target create "/boot/panic/kernel" --core "/var/crash/vmcore.last"
Core file '/var/crash/vmcore.last' (x86_64) was loaded.
(lldb) bt
* thread llvm#18, name = '(pid 5409) powerd (crashed)', stop reason = kernel panic
  * frame #0: 0xffffffff80bc6c91 kernel`__curthread at pcpu_aux.h:57:2 [inlined]
    frame #1: 0xffffffff80bc6c91 kernel`doadump(textdump=0) at kern_shutdown.c:399:2
    frame llvm#2: 0xffffffff804b3b7a kernel`db_dump(dummy=<unavailable>, dummy2=<unavailable>, dummy3=<unavailable>, dummy4=<unavailable>) at db_command.c:596:10
    frame llvm#3: 0xffffffff804b396d kernel`db_command(last_cmdp=<unavailable>, cmd_table=<unavailable>, dopager=true) at db_command.c:508:3
    frame llvm#4: 0xffffffff804b362d kernel`db_command_loop at db_command.c:555:3
    frame llvm#5: 0xffffffff804b7026 kernel`db_trap(type=<unavailable>, code=<unavailable>) at db_main.c:267:3
    frame llvm#6: 0xffffffff80c16aaf kernel`kdb_trap(type=3, code=0, tf=0xfffffe01b605b930) at subr_kdb.c:790:13
    frame llvm#7: 0xffffffff8112154e kernel`trap(frame=<unavailable>) at trap.c:614:8
    frame llvm#8: 0xffffffff810f14c8 kernel`calltrap at exception.S:285
    frame llvm#9: 0xffffffff81da2290 kernel`cn_devtab + 64
    frame llvm#10: 0xfffffe01b605b8b0
    frame llvm#11: 0xffffffff84001c43 dtrace.ko`dtrace_panic(format=<unavailable>) at dtrace.c:652:2
    frame llvm#12: 0xffffffff84005524 dtrace.ko`dtrace_action_panic(ecb=0xfffff80539cad580) at dtrace.c:7022:2 [inlined]
    frame llvm#13: 0xffffffff840054de dtrace.ko`dtrace_probe(id=88998, arg0=14343377283488, arg1=<unavailable>, arg2=<unavailable>, arg3=<unavailable>, arg4=<unavailable>) at dtrace.c:7665:6
    frame llvm#14: 0xffffffff83e5213d systrace.ko`systrace_probe(sa=<unavailable>, type=<unavailable>, retval=<unavailable>) at systrace.c:226:2
    frame llvm#15: 0xffffffff8112318d kernel`syscallenter(td=0xfffff801318d5780) at subr_syscall.c:160:4 [inlined]
    frame llvm#16: 0xffffffff81123112 kernel`amd64_syscall(td=0xfffff801318d5780, traced=0) at trap.c:1208:2
    frame llvm#17: 0xffffffff810f1dbb kernel`fast_syscall_common at exception.S:570
```
mikolaj-pirog pushed a commit that referenced this pull request Feb 5, 2026
In this PR i move the insertion point in the
`yieldReplacementForFusedProducer` because i ran into some issue where a
`tensor.extract_slices` tried to use a result of `affine.apply` that was
inserted at the end of the block instead of the start of it.

This is the full error of the test i added before this change:

```mlir
third-party/llvm-project/mlir/test/Interfaces/TilingInterface/tile-fuse-and-yield-using-scfforall.mlir:83:11: error: operand #1 does not dominate this use
  %pack = linalg.pack %gen#1
          ^
third-party/llvm-project/mlir/test/Interfaces/TilingInterface/tile-fuse-and-yield-using-scfforall.mlir:83:11: note: see current operation: %24 = "tensor.extract_slice"(%23, %36, %8) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xf32>, index, index) -> tensor<?x1024xf32>
third-party/llvm-project/mlir/test/Interfaces/TilingInterface/tile-fuse-and-yield-using-scfforall.mlir:71:12: note: operand defined here (op in the same block)
  %gen:2 = linalg.generic {
           ^
// -----// IR Dump After InterpreterPass Failed (transform-interpreter) //----- //
#map = affine_map<(d0, d1) -> (d0, d1)>
#map1 = affine_map<(d0) -> (d0 * 16)>
#map2 = affine_map<(d0) -> (d0 * -16 + 32)>
#map3 = affine_map<(d0) -> (16, d0 * -16 + 32)>
#map4 = affine_map<(d0) -> (d0 - 1)>
"builtin.module"() ({
  "func.func"() <{function_type = (tensor<32x1024xf32>) -> (tensor<32x1024xf32>, tensor<2x512x16x2xi8>), sym_name = "fuse_pack_consumer_into_multi_output_generic"}> ({
  ^bb0(%arg1: tensor<32x1024xf32>):
    %2 = "arith.constant"() <{value = 0 : i8}> : () -> i8
    %3 = "tensor.empty"() : () -> tensor<32x1024xf32>
    %4 = "tensor.empty"() : () -> tensor<32x1024xi8>
    %5 = "tensor.empty"() : () -> tensor<2x512x16x2xi8>
    %6:2 = "linalg.generic"(%arg1, %3, %4) <{indexing_maps = [#map, #map, #map], iterator_types = [#linalg.iterator_type<parallel>, #linalg.iterator_type<parallel>], operandSegmentSizes = array<i32: 1, 2>}> ({
    ^bb0(%arg9: f32, %arg10: f32, %arg11: i8):
      %41 = "arith.fptoui"(%arg9) : (f32) -> i8
      "linalg.yield"(%arg9, %41) : (f32, i8) -> ()
    }) : (tensor<32x1024xf32>, tensor<32x1024xf32>, tensor<32x1024xi8>) -> (tensor<32x1024xf32>, tensor<32x1024xi8>)
    %7:3 = "scf.forall"(%5, %3, %4) <{operandSegmentSizes = array<i32: 0, 0, 0, 3>, staticLowerBound = array<i64: 0>, staticStep = array<i64: 1>, staticUpperBound = array<i64: 2>}> ({
    ^bb0(%arg2: index, %arg3: tensor<2x512x16x2xi8>, %arg4: tensor<32x1024xf32>, %arg5: tensor<32x1024xi8>):
      %8 = "affine.apply"(%arg2) <{map = #map1}> : (index) -> index
      %9 = "affine.apply"(%arg2) <{map = #map2}> : (index) -> index
      %10 = "affine.min"(%arg2) <{map = #map3}> : (index) -> index
      %11 = "affine.apply"(%10) <{map = #map4}> : (index) -> index
      %12 = "affine.apply"(%arg2) <{map = #map1}> : (index) -> index
      %13 = "affine.apply"(%10) <{map = #map4}> : (index) -> index
      %14 = "affine.apply"(%arg2) <{map = #map1}> : (index) -> index
      %15 = "affine.apply"(%10) <{map = #map4}> : (index) -> index
      %16 = "affine.apply"(%arg2) <{map = #map1}> : (index) -> index
      %17 = "affine.apply"(%10) <{map = #map4}> : (index) -> index
      %18 = "tensor.extract_slice"(%arg1, %12, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xf32>, index, index) -> tensor<?x1024xf32>
      %19 = "tensor.empty"() : () -> tensor<32x1024xf32>
      %20 = "tensor.extract_slice"(%19, %14, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xf32>, index, index) -> tensor<?x1024xf32>
      %21 = "tensor.extract_slice"(%3, %14, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xf32>, index, index) -> tensor<?x1024xf32>
      %22 = "tensor.empty"() : () -> tensor<32x1024xi8>
      %23 = "tensor.extract_slice"(%22, %16, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xi8>, index, index) -> tensor<?x1024xi8>
      %24 = "tensor.extract_slice"(%4, %16, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xi8>, index, index) -> tensor<?x1024xi8>
      %25 = "tensor.empty"() : () -> tensor<32x1024xf32>
      %26 = "tensor.extract_slice"(%25, %38, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xf32>, index, index) -> tensor<?x1024xf32>
      %27 = "tensor.extract_slice"(%arg4, %38, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xf32>, index, index) -> tensor<?x1024xf32>
      %28 = "tensor.empty"() : () -> tensor<32x1024xi8>
      %29 = "tensor.extract_slice"(%28, %8, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xi8>, index, index) -> tensor<?x1024xi8>
      %30 = "tensor.extract_slice"(%arg5, %8, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xi8>, index, index) -> tensor<?x1024xi8>
      %31:2 = "linalg.generic"(%18, %27, %30) <{indexing_maps = [#map, #map, #map], iterator_types = [#linalg.iterator_type<parallel>, #linalg.iterator_type<parallel>], operandSegmentSizes = array<i32: 1, 2>}> ({
      ^bb0(%arg6: f32, %arg7: f32, %arg8: i8):
        %40 = "arith.fptoui"(%arg6) : (f32) -> i8
        "linalg.yield"(%arg6, %40) : (f32, i8) -> ()
      }) : (tensor<?x1024xf32>, tensor<?x1024xf32>, tensor<?x1024xi8>) -> (tensor<?x1024xf32>, tensor<?x1024xi8>)
      %32 = "tensor.extract_slice"(%6#1, %8, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xi8>, index, index) -> tensor<?x1024xi8>
      %33 = "tensor.empty"() : () -> tensor<2x512x16x2xi8>
      %34 = "tensor.extract_slice"(%33, %arg2) <{operandSegmentSizes = array<i32: 1, 1, 0, 0>, static_offsets = array<i64: -9223372036854775808, 0, 0, 0>, static_sizes = array<i64: 1, 512, 16, 2>, static_strides = array<i64: 1, 1, 1, 1>}> : (tensor<2x512x16x2xi8>, index) -> tensor<1x512x16x2xi8>
      %35 = "tensor.extract_slice"(%arg3, %arg2) <{operandSegmentSizes = array<i32: 1, 1, 0, 0>, static_offsets = array<i64: -9223372036854775808, 0, 0, 0>, static_sizes = array<i64: 1, 512, 16, 2>, static_strides = array<i64: 1, 1, 1, 1>}> : (tensor<2x512x16x2xi8>, index) -> tensor<1x512x16x2xi8>
      %36 = "linalg.pack"(%31#1, %35, %2) <{inner_dims_pos = array<i64: 0, 1>, operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_inner_tiles = array<i64: 16, 2>}> : (tensor<?x1024xi8>, tensor<1x512x16x2xi8>, i8) -> tensor<1x512x16x2xi8>
      %37 = "affine.apply"(%10) <{map = #map4}> : (index) -> index
      %38 = "affine.apply"(%arg2) <{map = #map1}> : (index) -> index
      %39 = "affine.apply"(%10) <{map = #map4}> : (index) -> index
      "scf.forall.in_parallel"() ({
        "tensor.parallel_insert_slice"(%36, %arg3, %arg2) <{operandSegmentSizes = array<i32: 1, 1, 1, 0, 0>, static_offsets = array<i64: -9223372036854775808, 0, 0, 0>, static_sizes = array<i64: 1, 512, 16, 2>, static_strides = array<i64: 1, 1, 1, 1>}> : (tensor<1x512x16x2xi8>, tensor<2x512x16x2xi8>, index) -> ()
        "tensor.parallel_insert_slice"(%31#0, %arg4, %38, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<?x1024xf32>, tensor<32x1024xf32>, index, index) -> ()
        "tensor.parallel_insert_slice"(%31#1, %arg5, %8, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<?x1024xi8>, tensor<32x1024xi8>, index, index) -> ()
      }) : () -> ()
    }) : (tensor<2x512x16x2xi8>, tensor<32x1024xf32>, tensor<32x1024xi8>) -> (tensor<2x512x16x2xi8>, tensor<32x1024xf32>, tensor<32x1024xi8>)
    "func.return"(%7#1, %7#0) : (tensor<32x1024xf32>, tensor<2x512x16x2xi8>) -> ()
  }) : () -> ()
  "builtin.module"() ({
    "transform.named_sequence"() <{arg_attrs = [{transform.readonly}], function_type = (!transform.any_op) -> (), sym_name = "__transform_main"}> ({
    ^bb0(%arg0: !transform.any_op):
      %0 = "transform.structured.match"(%arg0) <{ops = ["linalg.pack"]}> : (!transform.any_op) -> !transform.any_op
      %1:2 = "transform.test.fuse_and_yield"(%0) <{tile_interchange = [], tile_sizes = [1], use_forall = true}> : (!transform.any_op) -> (!transform.any_op, !transform.any_op)
      "transform.yield"() : () -> ()
    }) : () -> ()
  }) {transform.with_named_sequence} : () -> ()
}) : () -> ()
``` 

I also noticed that Interface tests are missing from the bazel overlay
so i also added this.
mikolaj-pirog pushed a commit that referenced this pull request Feb 5, 2026
…m#167446)

Add SVE optimization for AArch64 architectures. The idea is to use
predicate registers to avoid branching.
Microbench in repo shows considerable improvements on NV GB10 (locked on
largest X925):

```
======================================================================
BENCHMARK STATISTICS (time in nanoseconds)
======================================================================

memcpy_Google_A:
  Old - Mean: 3.1257 ns, Median: 3.1162 ns
  New - Mean: 2.8402 ns, Median: 2.8265 ns
  Improvement: +9.14% (mean), +9.30% (median)

memcpy_Google_B:
  Old - Mean: 2.3171 ns, Median: 2.3159 ns
  New - Mean: 1.6589 ns, Median: 1.6593 ns
  Improvement: +28.40% (mean), +28.35% (median)

memcpy_Google_D:
  Old - Mean: 8.7602 ns, Median: 8.7645 ns
  New - Mean: 8.4307 ns, Median: 8.4308 ns
  Improvement: +3.76% (mean), +3.81% (median)

memcpy_Google_L:
  Old - Mean: 1.7137 ns, Median: 1.7091 ns
  New - Mean: 1.4530 ns, Median: 1.4553 ns
  Improvement: +15.22% (mean), +14.85% (median)

memcpy_Google_M:
  Old - Mean: 1.9823 ns, Median: 1.9825 ns
  New - Mean: 1.4826 ns, Median: 1.4840 ns
  Improvement: +25.20% (mean), +25.15% (median)

memcpy_Google_Q:
  Old - Mean: 1.6812 ns, Median: 1.6784 ns
  New - Mean: 1.1538 ns, Median: 1.1517 ns
  Improvement: +31.37% (mean), +31.38% (median)

memcpy_Google_S:
  Old - Mean: 2.1816 ns, Median: 2.1786 ns
  New - Mean: 1.6297 ns, Median: 1.6287 ns
  Improvement: +25.29% (mean), +25.24% (median)

memcpy_Google_U:
  Old - Mean: 2.2851 ns, Median: 2.2825 ns
  New - Mean: 1.7219 ns, Median: 1.7187 ns
  Improvement: +24.65% (mean), +24.70% (median)

memcpy_Google_W:
  Old - Mean: 2.0408 ns, Median: 2.0361 ns
  New - Mean: 1.5260 ns, Median: 1.5252 ns
  Improvement: +25.23% (mean), +25.09% (median)

uniform_384_to_4096:
  Old - Mean: 26.9067 ns, Median: 26.8845 ns
  New - Mean: 26.8083 ns, Median: 26.8149 ns
  Improvement: +0.37% (mean), +0.26% (median)
```
The beginning of the memcpy function looks like the following:
```
Dump of assembler code for function _ZN22__llvm_libc_22_0_0_git6memcpyEPvPKvm:
   0x0000000000001340 <+0>:     cbz     x2, 0x143c <_ZN22__llvm_libc_22_0_0_git6memcpyEPvPKvm+252>
   0x0000000000001344 <+4>:     cbz     x0, 0x1440 <_ZN22__llvm_libc_22_0_0_git6memcpyEPvPKvm+256>
   0x0000000000001348 <+8>:     cbz     x1, 0x1444 <_ZN22__llvm_libc_22_0_0_git6memcpyEPvPKvm+260>
   0x000000000000134c <+12>:    subs    x8, x2, #0x20
   0x0000000000001350 <+16>:    b.hi    0x1374 <_ZN22__llvm_libc_22_0_0_git6memcpyEPvPKvm+52>  // b.pmore
   0x0000000000001354 <+20>:    rdvl    x8, #1
   0x0000000000001358 <+24>:    whilelo p0.b, xzr, x2
   0x000000000000135c <+28>:    ld1b    {z0.b}, p0/z, [x1]
   0x0000000000001360 <+32>:    whilelo p1.b, x8, x2
   0x0000000000001364 <+36>:    ld1b    {z1.b}, p1/z, [x1, #1, mul vl]
   0x0000000000001368 <+40>:    st1b    {z0.b}, p0, [x0]
   0x000000000000136c <+44>:    st1b    {z1.b}, p1, [x0, #1, mul vl]
   0x0000000000001370 <+48>:    ret
```

---------

Co-authored-by: Guillaume Chatelet <chatelet.guillaume@gmail.com>
mikolaj-pirog pushed a commit that referenced this pull request Feb 12, 2026
…8306)

In FreeBSD, allproc is a prepend list and new processes are appended at
head. This results in reverse pid order, so we first need to order pid
incrementally then print threads according to the correct order.

Before:
```
Process 0 stopped
* thread #1: tid = 101866, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff8015882f780, flags=259) at sched_ule.c:2448:26, name = '(pid 12991) dtrace'
  thread llvm#2: tid = 101915, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff80158825780, flags=259) at sched_ule.c:2448:26, name = '(pid 11509) zsh'
  thread llvm#3: tid = 101942, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff80142599000, flags=259) at sched_ule.c:2448:26, name = '(pid 11504) ftcleanup'
  thread llvm#4: tid = 101545, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff80131898000, flags=259) at sched_ule.c:2448:26, name = '(pid 5599) zsh'
  thread llvm#5: tid = 100905, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff80131899000, flags=259) at sched_ule.c:2448:26, name = '(pid 5598) sshd-session'
  thread llvm#6: tid = 101693, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff8015886e780, flags=259) at sched_ule.c:2448:26, name = '(pid 5595) sshd-session'
  thread llvm#7: tid = 101626, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff801588be000, flags=259) at sched_ule.c:2448:26, name = '(pid 5592) sh'
...
```

After:
```
(lldb) thread list
Process 0 stopped
* thread #1: tid = 100000, 0xffffffff80bf9322 kernel`sched_switch(td=0xffffffff81abe840, flags=259) at sched_ule.c:2448:26, name = '(pid 0) kernel'
  thread llvm#2: tid = 100035, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff801052d9780, flags=259) at sched_ule.c:2448:26, name = '(pid 0) kernel/softirq_0'
  thread llvm#3: tid = 100036, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff801052d9000, flags=259) at sched_ule.c:2448:26, name = '(pid 0) kernel/softirq_1'
  thread llvm#4: tid = 100037, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff801052d8780, flags=259) at sched_ule.c:2448:26, name = '(pid 0) kernel/softirq_2'
  thread llvm#5: tid = 100038, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff801052d8000, flags=259) at sched_ule.c:2448:26, name = '(pid 0) kernel/softirq_3'
  thread llvm#6: tid = 100039, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff801052d7780, flags=259) at sched_ule.c:2448:26, name = '(pid 0) kernel/softirq_4'
  thread llvm#7: tid = 100040, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff801052d7000, flags=259) at sched_ule.c:2448:26, name = '(pid 0) kernel/softirq_5'
...
```

Signed-off-by: Minsoo Choo <minsoochoo0122@proton.me>
mikolaj-pirog pushed a commit that referenced this pull request Feb 22, 2026
…er. (llvm#181941)

The progress event reporter has a thread that reports events every 250
millisecond. and is destroyed in its destructor.

When in event reporter desctructor, the event reporter may have pending
event but the call mutex is destroyed leading to the crash.

Relevant stack trace from CI.
```
[2026-02-13T17:46:13.577Z] libc++abi: terminating due to uncaught exception of type std::__1::system_error: mutex lock failed: Invalid argument 
[2026-02-13T17:46:13.577Z] PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash report from ~/Library/Logs/DiagnosticReports/. 

[2026-02-13T17:46:13.577Z]  #0 0x0000000102b6943c llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake-os-verficiation/lldb-build/bin/lldb-dap+0x10008943c) 
[2026-02-13T17:46:13.577Z]  #1 0x0000000102b67368 llvm::sys::RunSignalHandlers() (/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake-os-verficiation/lldb-build/bin/lldb-dap+0x100087368) 
[2026-02-13T17:46:13.577Z]  llvm#2 0x0000000102b69f20 SignalHandler(int, __siginfo*, void*) (/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake-os-verficiation/lldb-build/bin/lldb-dap+0x100089f20)
[2026-02-13T17:46:13.577Z]  llvm#3 0x000000018bbdb744 (/usr/lib/system/libsystem_platform.dylib+0x1804e3744) 
[2026-02-13T17:46:13.577Z]  llvm#4 0x000000018bbd1888 (/usr/lib/system/libsystem_pthread.dylib+0x1804d9888) 
[2026-02-13T17:46:13.577Z]  llvm#5 0x000000018bad6850 (/usr/lib/system/libsystem_c.dylib+0x1803de850) 
[2026-02-13T17:46:13.577Z]  llvm#6 0x000000018bb85858 (/usr/lib/libc++abi.dylib+0x18048d858) 
[2026-02-13T17:46:13.577Z]  llvm#7 0x000000018bb744bc (/usr/lib/libc++abi.dylib+0x18047c4bc) 
[2026-02-13T17:46:13.577Z]  llvm#8 0x000000018b7a0424 (/usr/lib/libobjc.A.dylib+0x1800a8424) 
[2026-02-13T17:46:13.577Z]  llvm#9 0x000000018bb84c2c (/usr/lib/libc++abi.dylib+0x18048cc2c) 
[2026-02-13T17:46:13.577Z] llvm#10 0x000000018bb88394 (/usr/lib/libc++abi.dylib+0x180490394) 
[2026-02-13T17:46:13.577Z] llvm#11 0x000000018bb8833c (/usr/lib/libc++abi.dylib+0x18049033c) 
[2026-02-13T17:46:13.577Z] llvm#12 0x000000018bb01b90 (/usr/lib/libc++.1.dylib+0x180409b90) 
[2026-02-13T17:46:13.577Z] llvm#13 0x000000018bb01b34 (/usr/lib/libc++.1.dylib+0x180409b34) 
[2026-02-13T17:46:13.577Z] llvm#14 0x000000018bb038a0 (/usr/lib/libc++.1.dylib+0x18040b8a0) 
[2026-02-13T17:46:13.577Z] llvm#15 0x0000000102b6fbac lldb_dap::DAP::Send(std::__1::variant<lldb_dap::protocol::Request, lldb_dap::protocol::Response, lldb_dap::protocol::Event> const&) (/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake-os-verficiation/lldb-build/bin/lldb-dap+0x10008fbac) 
[2026-02-13T17:46:13.577Z] llvm#16 0x0000000102b6f890 lldb_dap::DAP::SendJSON(llvm::json::Value const&) (/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake-os-verficiation/lldb-build/bin/lldb-dap+0x10008f890) 
[2026-02-13T17:46:13.577Z] llvm#17 0x0000000102b78788 std::__1::__function::__func<lldb_dap::DAP::DAP(lldb_dap::Log&, lldb_dap::ReplMode, std::__1::vector<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>, std::__1::allocator<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>>>, bool, llvm::StringRef, lldb_private::transport::JSONTransport<lldb_dap::ProtocolDescriptor>&, lldb_private::MainLoopPosix&)::$_0, std::__1::allocator<lldb_dap::DAP::DAP(lldb_dap::Log&, lldb_dap::ReplMode, std::__1::vector<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>, std::__1::allocator<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>>>, bool, llvm::StringRef, lldb_private::transport::JSONTransport<lldb_dap::ProtocolDescriptor>&, lldb_private::MainLoopPosix&)::$_0>, void (lldb_dap::ProgressEvent&)>::operator()(lldb_dap::ProgressEvent&) (/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake-os-verficiation/lldb-build/bin/lldb-dap+0x100098788) 
[2026-02-13T17:46:13.577Z] llvm#18 0x0000000102b8939c lldb_dap::ProgressEventManager::ReportIfNeeded() (/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake-os-verficiation/lldb-build/bin/lldb-dap+0x1000a939c) 
[2026-02-13T17:46:13.577Z] llvm#19 0x0000000102b8982c lldb_dap::ProgressEventReporter::ReportStartEvents() (/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake-os-verficiation/lldb-build/bin/lldb-dap+0x1000a982c) 
[2026-02-13T17:46:13.577Z] llvm#20 0x0000000102b8a038 void* std::__1::__thread_proxy[abi:nn200100]<std::__1::tuple<std::__1::unique_ptr<std::__1::__thread_struct, std::__1::default_delete<std::__1::__thread_struct>>, lldb_dap::ProgressEventReporter::ProgressEventReporter(std::__1::function<void (lldb_dap::ProgressEvent&)>)::$_0>>(void*) (/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake-os-verficiation/lldb-build/bin/lldb-dap+0x1000aa038) 
[2026-02-13T17:46:13.577Z] llvm#21 0x000000018bbd1c08 (/usr/lib/system/libsystem_pthread.dylib+0x1804d9c08) [2026-02-13T17:46:13.577Z] llvm#22 0x000000018bbccba8 (/usr/lib/system/libsystem_pthread.dylib+0x1804d4ba8)
```
rdar://170331108
mikolaj-pirog pushed a commit that referenced this pull request Feb 22, 2026
I created an issue about this in llvm#179976.

Clang's Address Sanitizer installs its own SEH filter which handles some
types of uncaught exceptions. Along with register values and some other
information, it also generates a stack trace. However, current logic is
incomplete. It relies on DbgHelp's SymFunctionTableAccess64 and
SymGetModuleBase64 which won't work with machine code that has its
RUNTIME_FUNCTION entry registered with Rtl* (e.g. RtlAddFunctionTable)
system calls. Most likely, this is because DbgHelp either relies on
information in PDB files or considers PDATA and XDATA only from loaded
EXE and DLL modules. Either way, consider the following example:

```
#include <windows.h>
#include <iostream>
#include <vector>

typedef union _UNWIND_CODE {
    struct {
        BYTE CodeOffset;
        BYTE UnwindOp : 4;
        BYTE OpInfo : 4;
    };
    USHORT FrameOffset;
} UNWIND_CODE, * PUNWIND_CODE;

typedef struct _UNWIND_INFO {
    BYTE Version : 3;
    BYTE Flags : 5;
    BYTE SizeOfProlog;
    BYTE CountOfCodes;
    BYTE FrameRegister : 4;
    BYTE FrameOffset : 4;
    UNWIND_CODE UnwindCode[1]; // Variable size
} UNWIND_INFO, * PUNWIND_INFO;

#define UWOP_PUSH_NONVOL      0
#define UWOP_ALLOC_LARGE      1
#define UWOP_ALLOC_SMALL      2
#define UWOP_SET_FPREG        3
#define UWOP_SAVE_NONVOL      4
#define UWOP_SAVE_NONVOL_FAR  5
#define UWOP_SAVE_XMM128      8
#define UWOP_SAVE_XMM128_FAR  9
#define UWOP_PUSH_MACHFRAME   10

int main() {
    // PUSH RBX         (0x53)                - Save non-volatile register
    // SUB RSP, 0x20    (0x48 0x83 0xEC 0x20) - Allocate 32 bytes (shadow space)
    // XOR RAX, RAX     (0x48 0x31 0xC0)      - Zero out RAX
    // MOV RAX, [RAX]   (0x48 0x8B 0x00)      - Dereference NULL
    
    std::vector<unsigned char> code = {
        0x53,
        0x48, 0x83, 0xEC, 0x20,
        0x48, 0x31, 0xC0,
        0x48, 0x8B, 0x00
    };

    size_t codeSize = code.size();
    size_t totalSize = 100;

    LPVOID pMemory = VirtualAlloc(NULL, totalSize, MEM_COMMIT | MEM_RESERVE, PAGE_EXECUTE_READWRITE);
    
    BYTE* pCodeBase = (BYTE*)pMemory;
    PUNWIND_INFO pUnwindInfo = (PUNWIND_INFO)(pCodeBase + codeSize);    

    size_t alignmentPadding = 0;
    if ((size_t)pUnwindInfo % 4 != 0) {
        alignmentPadding = 4 - ((size_t)pUnwindInfo % 4);
        pUnwindInfo = (PUNWIND_INFO)((BYTE*)pUnwindInfo + alignmentPadding);
    }

    memcpy(pCodeBase, code.data(), codeSize);

    pUnwindInfo->Version = 1;
    pUnwindInfo->Flags = UNW_FLAG_NHANDLER;
    pUnwindInfo->Flags = 0; 
    pUnwindInfo->SizeOfProlog = 5; 
    pUnwindInfo->CountOfCodes = 2; 
    pUnwindInfo->FrameRegister = 0;
    pUnwindInfo->FrameOffset = 0;

    pUnwindInfo->UnwindCode[0].CodeOffset = 5;
    pUnwindInfo->UnwindCode[0].UnwindOp = UWOP_ALLOC_SMALL;
    pUnwindInfo->UnwindCode[0].OpInfo = 3; 

    pUnwindInfo->UnwindCode[1].CodeOffset = 1;
    pUnwindInfo->UnwindCode[1].UnwindOp = UWOP_PUSH_NONVOL;
    pUnwindInfo->UnwindCode[1].OpInfo = 3; // RBX

    RUNTIME_FUNCTION tableEntry = {};
    tableEntry.BeginAddress = 0;
    tableEntry.EndAddress = (DWORD)codeSize;
    tableEntry.UnwindData = (DWORD)((BYTE*)pUnwindInfo - (BYTE*)pMemory);

    DWORD64 baseAddress = (DWORD64)pMemory;
    RtlAddFunctionTable(&tableEntry, 1, baseAddress);

    typedef void(*FuncType)();
    FuncType myFunc = (FuncType)pMemory;
    myFunc();

    return 0;
}
```

Windows' kernel can propagate hardware exception through that function,
so clearly these entries are at least partially correct. Right now,
ASan's stack walking produces this (compiled with latest release,
clang++):

```
PS D:\Local Projects\cpp-playground> ./a.exe
=================================================================
==14216==ERROR: AddressSanitizer: access-violation on unknown address 0x000000000000 (pc 0x0199561c0008 bp 0x004cf0cffb30 sp 0x004cf0cff970 T0)
==14216==The signal is caused by a READ memory access.
==14216==Hint: address points to the zero page.
    #0 0x0199561c0007  (<unknown module>)
    #1 0x000000000000  (<unknown module>)
    llvm#2 0x000000000000  (<unknown module>)

==14216==Register values:
rax = 0  rbx = 4cf0cffaa0  rcx = 7ffcb97b4e28  rdx = 19955dc0000
rdi = 11bf564a0040  rsi = 0  rbp = 4cf0cffb30  rsp = 4cf0cff970
r8  = 7ffffffffffffffc  r9  = 1  r10 = 0  r11 = 246
r12 = 0  r13 = 0  r14 = 0  r15 = 0
AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: access-violation (<unknown module>)
==14216==ABORTING
```

Frames one and two is just some stack space allocated by that dynamic
function. While patched version produces this:

```
PS D:\Local Projects\cpp-playground> ./a.exe
=================================================================
==13660==ERROR: AddressSanitizer: access-violation on unknown address 0x000000000000 (pc 0x01ed5ad70008 bp 0x00d76492f650 sp 0x00d76492f490 T0)
==13660==The signal is caused by a READ memory access.
==13660==Hint: address points to the zero page.
    #0 0x01ed5ad70007  (<unknown module>)
    #1 0x7ff732e518a1 in main (D:\Local Projects\cpp-playground\a.exe+0x1400018a1)
    llvm#2 0x7ff732e56a9b in invoke_main D:\a\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:78
    llvm#3 0x7ff732e56a9b in __scrt_common_main_seh D:\a\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288
    llvm#4 0x7ffcb878e8d6  (C:\WINDOWS\System32\KERNEL32.DLL+0x18002e8d6)
    llvm#5 0x7ffcb966c53b  (C:\WINDOWS\SYSTEM32\ntdll.dll+0x18008c53b)

==13660==Register values:
rax = 0  rbx = d76492f5c0  rcx = 7ffcb97b4e28  rdx = 1ed5a870000
rdi = 12135afa0040  rsi = 0  rbp = d76492f650  rsp = d76492f490
r8  = 7ffffffffffffffc  r9  = 1  r10 = 0  r11 = 246
r12 = 0  r13 = 0  r14 = 0  r15 = 0
AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: access-violation (<unknown module>)
==13660==ABORTING
```

Now we see that stack walking handled our dynamic function properly.
Interestingly enough, it appears that other overloaded version of
UnwindSlow procedure that works without CONTEXT structure already has
some logic to handle this. Theoretically, symbolizer should also be able
to provide some information about these functions, but I don't think
that this is necessary.

I added SANITIZER_WINDOWS64 check because I am pretty sure Microsoft
only mentions these functions for 64 bit version of their OS. I also
can't check how this works on ARM.
mikolaj-pirog pushed a commit that referenced this pull request Mar 13, 2026
Using code/ideas from the x86 backend to optimize a select on a bitcast
integer. The previous aarch64 approach was to individually extract the
bits from the mask, which is kind of terrible.

https://rust.godbolt.org/z/576sndT66

```llvm
define void @if_then_else8(ptr %out, i8 %mask, ptr %if_true, ptr %if_false) {
start:
  %t = load <8 x i32>, ptr %if_true, align 4
  %f = load <8 x i32>, ptr %if_false, align 4
  %m = bitcast i8 %mask to <8 x i1>
  %s = select <8 x i1> %m, <8 x i32> %t, <8 x i32> %f
  store <8 x i32> %s, ptr %out, align 4
  ret void
}
```

turned into 

```asm
if_then_else8:                          // @if_then_else8
        sub     sp, sp, llvm#16
        ubfx    w8, w1, llvm#4, #1
        and     w11, w1, #0x1
        ubfx    w9, w1, llvm#5, #1
        fmov    s1, w11
        ubfx    w10, w1, #1, #1
        fmov    s0, w8
        ubfx    w8, w1, llvm#6, #1
        ldp     q5, q2, [x3]
        mov     v1.h[1], w10
        ldp     q4, q3, [x2]
        mov     v0.h[1], w9
        ubfx    w9, w1, llvm#2, #1
        mov     v1.h[2], w9
        ubfx    w9, w1, llvm#3, #1
        mov     v0.h[2], w8
        ubfx    w8, w1, llvm#7, #1
        mov     v1.h[3], w9
        mov     v0.h[3], w8
        ushll   v1.4s, v1.4h, #0
        ushll   v0.4s, v0.4h, #0
        shl     v1.4s, v1.4s, llvm#31
        shl     v0.4s, v0.4s, llvm#31
        cmlt    v1.4s, v1.4s, #0
        cmlt    v0.4s, v0.4s, #0
        bsl     v1.16b, v4.16b, v5.16b
        bsl     v0.16b, v3.16b, v2.16b
        stp     q1, q0, [x0]
        add     sp, sp, llvm#16
        ret
```

With this PR that instead emits

```asm
if_then_else8:
   adrp x8, .LCPI0_1
   dup v0.4s, w1
   ldr q1, [x8, :lo12:.LCPI0_1]
   adrp x8, .LCPI0_0
   ldr q2, [x8, :lo12:.LCPI0_0]
   ldp q4, q3, [x2]
   and v1.16b, v0.16b, v1.16b
   and v0.16b, v0.16b, v2.16b
   ldp q5, q2, [x3]
   cmeq v1.4s, v1.4s, #0
   cmeq v0.4s, v0.4s, #0
   bsl v1.16b, v2.16b, v3.16b
   bsl v0.16b, v5.16b, v4.16b
   stp q0, q1, [x0]
   ret
```

So substantially shorter. Instead of building the mask
element-by-element, this approach (by virtue of not splitting) instead
splats the mask value into all vector lanes, performs a bitwise and with
powers of 2, and compares with zero to construct the mask vector.

cc rust-lang/rust#122376
cc llvm#175769
mikolaj-pirog pushed a commit that referenced this pull request Mar 13, 2026
llvm#184186)

…83889)"

This reverts commit 2342db0.

Revert "[CMake] Propagate dependencies to OBJECT libraries in
`add_llvm_library` (llvm#183541)"

This reverts commit e3c0454.
mikolaj-pirog pushed a commit that referenced this pull request Mar 13, 2026
`SE.getUMaxExpr` causes assertion failure due to type mismatch here:


https://github.com/llvm/llvm-project/blob/main/llvm/lib/Analysis/LoopAccessAnalysis.cpp#L253

Running `opt -S -p loop-vectorize -debug-only=loop-vectorize
llvm/test/Analysis/LoopAccessAnalysis/type-mismatch-in-scalar-evolution.ll
` without the changes made in LoopAccessAnalysis.cpp causes assertion
failure.
Attaching the stack dump for reference:
```
LV: Checking a loop in 'loop_contains_store_assumed_bounds' from input.ll
LV: Loop hints: force=? width=4 interleave=0
LV: Found a loop: for.body
LV: Found an induction variable.
opt: /home/kshitij/llvm-project/llvm/lib/Analysis/ScalarEvolution.cpp:3918: const llvm::SCEV* llvm::ScalarEvolution::getMinMaxExpr(llvm::SCEVTypes, llvm::SmallVectorImpl<const llvm::SCEV*>&): Assertion `getEffectiveSCEVType(Ops[i]->getType()) == ETy && "Operand types don't match!"' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace and instructions to reproduce the bug.
Stack dump:
0.	Program arguments: opt -S -passes=loop-vectorize -debug-only=loop-vectorize -force-vector-width=4 -disable-output input.ll
1.	Running pass "function(loop-vectorize<no-interleave-forced-only;no-vectorize-forced-only;>)" on module "input.ll"
2.	Running pass "loop-vectorize<no-interleave-forced-only;no-vectorize-forced-only;>" on function "loop_contains_store_assumed_bounds"
 #0 0x000058ee97c5e652 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/usr/local/bin/opt+0x4f44652)
 #1 0x000058ee97c5af0f llvm::sys::RunSignalHandlers() (/usr/local/bin/opt+0x4f40f0f)
 llvm#2 0x000058ee97c5b05c SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
 llvm#3 0x00007c49d4c45330 (/lib/x86_64-linux-gnu/libc.so.6+0x45330)
 llvm#4 0x00007c49d4c9eb2c __pthread_kill_implementation ./nptl/pthread_kill.c:44:76
 llvm#5 0x00007c49d4c9eb2c __pthread_kill_internal ./nptl/pthread_kill.c:78:10
 llvm#6 0x00007c49d4c9eb2c pthread_kill ./nptl/pthread_kill.c:89:10
 llvm#7 0x00007c49d4c4527e raise ./signal/../sysdeps/posix/raise.c:27:6
 llvm#8 0x00007c49d4c288ff abort ./stdlib/abort.c:81:7
 llvm#9 0x00007c49d4c2881b _nl_load_domain ./intl/loadmsgcat.c:1177:9
llvm#10 0x00007c49d4c3b517 (/lib/x86_64-linux-gnu/libc.so.6+0x3b517)
llvm#11 0x000058ee98003fdb llvm::ScalarEvolution::getMinMaxExpr(llvm::SCEVTypes, llvm::SmallVectorImpl<llvm::SCEV const*>&) (/usr/local/bin/opt+0x52e9fdb)
llvm#12 0x000058ee98004507 llvm::ScalarEvolution::getUMaxExpr(llvm::SCEV const*, llvm::SCEV const*) (/usr/local/bin/opt+0x52ea507)
llvm#13 0x000058ee980dc728 llvm::getStartAndEndForAccess(llvm::Loop const*, llvm::SCEV const*, llvm::Type*, llvm::SCEV const*, llvm::SCEV const*, llvm::ScalarEvolution*, llvm::DenseMap<std::pair<llvm::SCEV const*, llvm::Type*>, std::pair<llvm::SCEV const*, llvm::SCEV const*>, llvm::DenseMapInfo<std::pair<llvm::SCEV const*, llvm::Type*>, void>, llvm::detail::DenseMapPair<std::pair<llvm::SCEV const*, llvm::Type*>, std::pair<llvm::SCEV const*, llvm::SCEV const*>>>*, llvm::DominatorTree*, llvm::AssumptionCache*, std::optional<llvm::ScalarEvolution::LoopGuards>&) (/usr/local/bin/opt+0x53c2728)
llvm#14 0x000058ee9814008b llvm::isDereferenceableAndAlignedInLoop(llvm::LoadInst*, llvm::Loop*, llvm::ScalarEvolution&, llvm::DominatorTree&, llvm::AssumptionCache*, llvm::SmallVectorImpl<llvm::SCEVPredicate const*>*) (/usr/local/bin/opt+0x542608b)
llvm#15 0x000058ee9a0fa1ca llvm::LoopVectorizationLegality::canUncountableExitConditionLoadBeMoved(llvm::BasicBlock*) (/usr/local/bin/opt+0x73e01ca)
llvm#16 0x000058ee9a0faee0 llvm::LoopVectorizationLegality::isVectorizableEarlyExitLoop() (/usr/local/bin/opt+0x73e0ee0)
llvm#17 0x000058ee9a104678 llvm::LoopVectorizationLegality::canVectorize(bool) (/usr/local/bin/opt+0x73ea678)
llvm#18 0x000058ee9a08c953 llvm::LoopVectorizePass::processLoop(llvm::Loop*) (/usr/local/bin/opt+0x7372953)
llvm#19 0x000058ee9a090e21 llvm::LoopVectorizePass::runImpl(llvm::Function&) (/usr/local/bin/opt+0x7376e21)
llvm#20 0x000058ee9a0914e0 llvm::LoopVectorizePass::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/usr/local/bin/opt+0x73774e0)
llvm#21 0x000058ee99e419a5 llvm::detail::PassModel<llvm::Function, llvm::LoopVectorizePass, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) PassBuilderPipelines.cpp:0:0
llvm#22 0x000058ee97f18905 llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/usr/local/bin/opt+0x51fe905)
llvm#23 0x000058ee995d70d5 llvm::detail::PassModel<llvm::Function, llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) AMDGPUTargetMachine.cpp:0:0
llvm#24 0x000058ee97f17051 llvm::ModuleToFunctionPassAdaptor::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/usr/local/bin/opt+0x51fd051)
llvm#25 0x000058ee995d7775 llvm::detail::PassModel<llvm::Module, llvm::ModuleToFunctionPassAdaptor, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) AMDGPUTargetMachine.cpp:0:0
llvm#26 0x000058ee97f1783d llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/usr/local/bin/opt+0x51fd83d)
llvm#27 0x000058ee9c153909 llvm::runPassPipeline(llvm::StringRef, llvm::Module&, llvm::TargetMachine*, llvm::TargetLibraryInfoImpl*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::StringRef, llvm::ArrayRef<llvm::PassPlugin>, llvm::ArrayRef<std::function<void (llvm::PassBuilder&)>>, llvm::opt_tool::OutputKind, llvm::opt_tool::VerifierKind, bool, bool, bool, bool, bool, bool, bool, bool) (/usr/local/bin/opt+0x9439909)
llvm#28 0x000058ee97c3f380 optMain (/usr/local/bin/opt+0x4f25380)
llvm#29 0x00007c49d4c2a1ca __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:74:3
llvm#30 0x00007c49d4c2a28b call_init ./csu/../csu/libc-start.c:128:20
llvm#31 0x00007c49d4c2a28b __libc_start_main ./csu/../csu/libc-start.c:347:5
llvm#32 0x000058ee97c309a5 _start (/usr/local/bin/opt+0x4f169a5)
```

This is caused by a type mismatch between
`SE.getSCEV(DerefRK.IRArgValue)` and `DerefBytesSCEV`.
Fixing this by extending them to the wider type.
mikolaj-pirog pushed a commit that referenced this pull request Jul 1, 2026
…lvm#191275)" (llvm#206816)

This reverts commit 0f51760.

A test fails with the commit
(llvm#191275 (comment)):

```
Traceback (most recent call last):
  File "/home/tcwg-buildbot/worker/lldb-aarch64-ubuntu/llvm-project/lldb/test/API/functionalities/scripted_frame_provider/TestScriptedFrameProvider.py", line 596, in test_python_source_frames
    self.assertNotIn("0xffffffffffffffff", output.lower())
AssertionError: '0xffffffffffffffff' unexpectedly found in "* thread llvm#2, name = 'a.out', stop reason = breakpoint 1.1\n  * frame #0: compute_fibonacci at python_helper.py:7 [synthetic]\n    frame #1: process_data at python_helper.py:16 [synthetic]\n    frame llvm#2: main at python_helper.py:27 [synthetic]\n    frame llvm#3: 0x0000badc2de81358 a.out`thread_func(thread_num=0) at main.cpp:44:13\n    frame llvm#4: 0x0000badc2de81f9c a.out`void std::__invoke_impl<void, void (*)(int), int>((null)=__invoke_other @ 0x0000f1555ebae74f, __f=0x0000badc66845ec0, __args=0x0000badc66845eb8) at invoke.h:61:14\n    frame llvm#5: 0x0000badc2de81f18 a.out`std::__invoke_result<void (*)(int), int>::type std::__invoke<void (*)(int), int>(__fn=0x0000badc66845ec0, __args=0x0000badc66845eb8) at invoke.h:96:14\n    frame llvm#6: 0x0000badc2de81ee4 a.out`void std::thread::_invoker<std::tuple<void (*)(int), int>>::_m_invoke<0ul, 1ul>(this=0x0000badc66845eb8, (null)=_index_tuple<0ul, 1ul> @ 0x0000f1555ebae7af) at std_thread.h:259:13\n    frame llvm#7: 0x0000badc2de81e98 a.out`std::thread::_invoker<std::tuple<void (*)(int), int>>::operator()(this=0x0000badc66845eb8) at std_thread.h:266:11\n    frame llvm#8: 0x0000badc2de81d70 a.out`std::thread::_state_impl<std::thread::_invoker<std::tuple<void (*)(int), int>>>::_m_run(this=0xffffffffffffffff) at std_thread.h:211:13\n    frame llvm#9: 0x0000f1555ef029cc libstdc++.so.6`___lldb_unnamed_symbol_d29b0 + 28\n    frame llvm#10: 0x0000f1555ec30398 libc.so.6`___lldb_unnamed_symbol_800c0 + 728\n    frame llvm#11: 0x0000f1555ec99e9c libc.so.6`___lldb_unnamed_symbol_e9e90 + 12\n"
```

I don't know why this test fails with the PR, but I don't have time to
fix it now, so revert it to unblock CI.

The backtrace was
```
    frame #0: compute_fibonacci at python_helper.py:7 [synthetic]
    frame #1: process_data at python_helper.py:16 [synthetic]
    frame llvm#2: main at python_helper.py:27 [synthetic]
    frame llvm#3: 0x0000badc2de81358 a.out`thread_func(thread_num=0) at main.cpp:44:13
    frame llvm#4: 0x0000badc2de81f9c a.out`void std::__invoke_impl<void, void (*)(int), int>((null)=__invoke_other @ 0x0000f1555ebae74f, __f=0x0000badc66845ec0, __args=0x0000badc66845eb8) at invoke.h:61:14
    frame llvm#5: 0x0000badc2de81f18 a.out`std::__invoke_result<void (*)(int), int>::type std::__invoke<void (*)(int), int>(__fn=0x0000badc66845ec0, __args=0x0000badc66845eb8) at invoke.h:96:14
    frame llvm#6: 0x0000badc2de81ee4 a.out`void std::thread::_invoker<std::tuple<void (*)(int), int>>::_m_invoke<0ul, 1ul>(this=0x0000badc66845eb8, (null)=_index_tuple<0ul, 1ul> @ 0x0000f1555ebae7af) at std_thread.h:259:13
    frame llvm#7: 0x0000badc2de81e98 a.out`std::thread::_invoker<std::tuple<void (*)(int), int>>::operator()(this=0x0000badc66845eb8) at std_thread.h:266:11
    frame llvm#8: 0x0000badc2de81d70 a.out`std::thread::_state_impl<std::thread::_invoker<std::tuple<void (*)(int), int>>>::_m_run(this=0xffffffffffffffff) at std_thread.h:211:13
    frame llvm#9: 0x0000f1555ef029cc libstdc++.so.6`___lldb_unnamed_symbol_d29b0 + 28
    frame llvm#10: 0x0000f1555ec30398 libc.so.6`___lldb_unnamed_symbol_800c0 + 728
    frame llvm#11: 0x0000f1555ec99e9c libc.so.6`___lldb_unnamed_symbol_e9e90 + 12
```

This contains 0xffffffffffffffff in frame 8.
mikolaj-pirog pushed a commit that referenced this pull request Jul 1, 2026
Summary

This builds on the accelerator plugin protocol
(llvm#201489) by letting a plugin
ask the client to create and connect a second
target — the mechanism a real backend (e.g. a GPU debug stub) uses to
surface
  the accelerator alongside the CPU process being debugged.

  ### What this adds

**Protocol** — a new `AcceleratorConnectionInfo` describing how the
client
  should bring up the accelerator target.

  **Client** — when an `AcceleratorActions` carries `connect_info`,
`ProcessGDBRemote` creates a new (empty) target, reverse-connects it to
the GDB
  server the plugin points.

  **Mock server (for testing)** — to exercise this end to end, the mock
accelerator plugin stands up an in-process GDB server backed by a
minimal fake
process: `ProcessMockAccelerator`, `ThreadMockAccelerator` and
`RegisterContextMockAccelerator`.

  ### Scope

Intentionally minimal: the goal is to create and show the second
(accelerator)
target. There is no register/memory modeling beyond what a connection
requires. Next set of PRs will build up on this.

  ### Testing


Demo of how this looks with this PR. (explicitly asking the native
process to stop at every breakpoint for testability)

```
satyajanga@devgpu011:toolchain $ ./bin/lldb
(lldb) file /home/satyajanga/llvm-sand/build/Debug/fbcode-x86_64/toolchain/lldb-test-build.noindex/accelerator/mock/TestMockAcceleratorActions/a.out                                     Current executable set to '/home/satyajanga/llvm-sand/build/Debug/fbcode-x86_64/toolchain/lldb-test-build.noindex/accelerator/mock/TestMockAcceleratorActions/a.out' (x86_64).
(lldb) log enable -f /tmp/packets.log gdb-remote packets                                                                                                                                 (lldb) r
Process 1430531 launched: '/home/satyajanga/llvm-sand/build/Debug/fbcode-x86_64/toolchain/lldb-test-build.noindex/accelerator/mock/TestMockAcceleratorActions/a.out' (x86_64)
Process 1430531 stopped
(lldb) target list
Current targets:
* target #0: /home/satyajanga/llvm-sand/build/Debug/fbcode-x86_64/toolchain/lldb-test-build.noindex/accelerator/mock/TestMockAcceleratorActions/a.out ( arch=x86_64-unknown-linux-gnu, platform=host, pid=1430531, state=stopped )
(lldb) c
Process 1430531 resuming
Process 1 stopped
* thread #1, name = 'Mock Accelerator Thread', stop reason = trace
       frame #0: 0x0000000000001004
error: memory read failed for 0x1000
Target 0: (a.out) stopped.
(lldb) target list
Current targets:
  target #0: /home/satyajanga/llvm-sand/build/Debug/fbcode-x86_64/toolchain/lldb-test-build.noindex/accelerator/mock/TestMockAcceleratorActions/a.out ( arch=x86_64-unknown-linux-gnu, platform=host, pid=1430531, state=stopped )
* target #1: <none> ( arch=x86_64-unknown-linux-gnu, platform=host, pid=1, state=stopped )
(lldb) c
Process 1 resuming
(lldb) target select 0
Current targets:
* target #0: /home/satyajanga/llvm-sand/build/Debug/fbcode-x86_64/toolchain/lldb-test-build.noindex/accelerator/mock/TestMockAcceleratorActions/a.out ( arch=x86_64-unknown-linux-gnu, platform=host, pid=1430531, state=stopped )
  target #1: <none> ( arch=x86_64-unknown-linux-gnu, platform=host, pid=1, state=running )
(lldb) c
Process 1430531 resuming
Process 1430531 stopped
(lldb) target list
Current targets:
* target #0: /home/satyajanga/llvm-sand/build/Debug/fbcode-x86_64/toolchain/lldb-test-build.noindex/accelerator/mock/TestMockAcceleratorActions/a.out ( arch=x86_64-unknown-linux-gnu, platform=host, pid=1430531, state=stopped )
  target #1: <none> ( arch=x86_64-unknown-linux-gnu, platform=host, pid=1, state=running )
(lldb)
a.out │ internal accelerator-plugin (mock) breakpoint(-4).
```

Packet log, 
you can notice the actions set with breakpoint info and later responding
with connection info. and you can also see the 5 GPRs

```
lldb             < 104> send packet: $qSupported:xmlRegisters=i386,arm,mips,arc;multiprocess+;fork-events+;vfork-events+;swbreak+;hwbreak+#cd
lldb             < 299> read packet: $PacketSize=131072;QStartNoAckMode+;qEcho+;native-signals+;QThreadSuffixSupported+;QListThreadsInStopReply+;qXfer:features:read+;QNonStop+;jMultiBreakpoint+;QPassSignals+;qXfer:auxv:read+;qXfer:libraries-svr4:read+;qXfer:siginfo:read+;accelerator-plugins+;multiprocess+;fork-events+;vfork-events+llvm#86
..
lldb             <  32> send packet: $jAcceleratorPluginInitialize#50
lldb             < 238> read packet: $[{"breakpoints":[{"by_address":null,"by_name":{"function_name":"mock_gpu_accelerator_initialize","shlib":null}],"identifier":1,"symbol_names":["mock_gpu_accelerator_compute"]}]],"identifier":1,"plugin_name":"mock","session_name":""}]]#2f
..
intern-state     < 314> send packet: $jAcceleratorPluginBreakpointHit:{"breakpoint":{"by_address":null,"by_name":{"function_name":"mock_gpu_accelerator_initialize","shlib":null}],"identifier":1,"symbol_names":["mock_gpu_accelerator_compute"]}],"plugin_name":"mock","symbol_values":[{"name":"mock_gpu_accelerator_compute","value":93824992235840}]]}]#e7
intern-state     < 487> read packet: ${"actions":{"breakpoints":[{"by_address":null,"by_name":{"function_name":"mock_gpu_accelerator_finish","shlib":"a.out"}],"identifier":3,"symbol_names":[]}],{"by_address":{"load_address":93824992235840}],"by_name":null,"identifier":2,"symbol_names":[]}],{"by_address":null,"by_name":{"function_name":"mock_gpu_accelerator_connect","shlib":null}],"identifier":4,"symbol_names":[]}]],"identifier":2,"plugin_name":"mock","session_name":""}],"auto_resume_native":false,"disable_bp":true}]#7d
..
..
intern-state     < 218> send packet: $jAcceleratorPluginBreakpointHit:{"breakpoint":{"by_address":null,"by_name":{"function_name":"mock_gpu_accelerator_connect","shlib":null}],"identifier":4,"symbol_names":[]}],"plugin_name":"mock","symbol_values":[]}]#d1
intern-state     < 268> read packet: ${"actions":{"breakpoints":[],"connect_info":{"connect_url":"connect://localhost:32893","exe_path":null,"synchronous":true,"triple":null}],"identifier":4,"plugin_name":"mock","session_name":"Mock Accelerator Session"}],"auto_resume_native":false,"disable_bp":true}]#8e
intern-state     <   1> send packet: +
intern-state     history[1] tid=0x15d41f <   1> send packet: +
intern-state     <  19> send packet: $QStartNoAckMode#b0
intern-state     <   1> read packet: +
intern-state     <   6> read packet: $OK#9a
intern-state     <   1> send packet: +
intern-state     < 104> send packet: $qSupported:xmlRegisters=i386,arm,mips,arc;multiprocess+;fork-events+;vfork-events+;swbreak+;hwbreak+#cd
intern-state     < 159> read packet: $PacketSize=131072;QStartNoAckMode+;qEcho+;native-signals+;QThreadSuffixSupported+;QListThreadsInStopReply+;qXfer:features:read+;QNonStop+;jMultiBreakpoint+#f3
intern-state     <  26> send packet: $QThreadSuffixSupported#e4
intern-state     <   6> read packet: $OK#9a
intern-state     <  27> send packet: $QListThreadsInStopReply#21
intern-state     <   6> read packet: $OK#9a
intern-state     <  13> send packet: $qHostInfo#9b
intern-state     < 364> read packet: $triple:7838365f36342d2d6c696e75782d676e75;ptrsize:8;watchpoint_exceptions_received:after;endian:little;os_version:6.13.2;os_build:362e31332e322d305f66626b355f
68617264656e65645f7263325f305f67313733613962316463613431;os_kernel:233120534d5020576564204a756c2032332030393a32343a3330205044542032303235;hostname:6465766770753031312e656167322e66616365626f6f6b2e6
36f6d;#c4
intern-state     <  10> send packet: $vCont?llvm#49
intern-state     <  19> read packet: $vCont;c;C;s;S;t#11
intern-state     <  27> send packet: $qVAttachOrWaitSupported#38
intern-state     <   6> read packet: $OK#9a
intern-state     <  23> send packet: $QEnableErrorStrings#8c
intern-state     <   6> read packet: $OK#9a
intern-state     <  16> send packet: $qProcessInfo#dc
intern-state     <   7> read packet: $E01#a6
intern-state     <   6> send packet: $qC#b4
intern-state     <   7> read packet: $QC1#c5
intern-state     <   5> send packet: $?#3f
intern-state     < 291> read packet: $T00thread:1;name:Mock Accelerator Thread;threads:1;thread-pcs:0000000000001004;00:0010000000000000;01:0110000000000000;02:0210000000000000;03:0310000000000000
;04:0410000000000000;05:0510000000000000;reason:trace;description:6d6f636b20616363656c657261746f72207468726561642073746f70706564;llvm#83
intern-state     <  16> send packet: $qProcessInfo#dc
intern-state     <   7> read packet: $E01#a6
intern-state     <  16> send packet: $qProcessInfo#dc
intern-state     <   7> read packet: $E01#a6
intern-state     <  43> send packet: $qXfer:features:read:target.xml:0,131071#78
intern-state     < 889> read packet: $l<?xml version="1.0"?>
<target version="1.0">
  <architecture>x86_64</architecture>
  <feature>
    <reg name="r0" bitsize="64" regnum="0" offset="0" encoding="uint" format="hex" group="General Purpose Registers" />
    <reg name="r1" bitsize="64" regnum="1" offset="8" encoding="uint" format="hex" group="General Purpose Registers" />
    <reg name="sp" bitsize="64" regnum="2" offset="16" encoding="uint" format="hex" group="General Purpose Registers" generic="sp" />
    <reg name="fp" bitsize="64" regnum="3" offset="24" encoding="uint" format="hex" group="General Purpose Registers" generic="fp" />
    <reg name="pc" bitsize="64" regnum="4" offset="32" encoding="uint" format="hex" group="General Purpose Registers" generic="pc" />
    <reg name="flags" bitsize="64" regnum="5" offset="40" encoding="uint" format="hex" group="General Purpose Registers" />
  </feature>
</target>
llvm#82
intern-state     <  19> send packet: $p0;thread:0001;llvm#89
intern-state     <  20> read packet: $0010000000000000#01
intern-state     <  16> send packet: $qProcessInfo#dc
intern-state     <   7> read packet: $E01#a6
intern-state     <  19> send packet: $p0;thread:0001;llvm#89
intern-state     <  20> read packet: $0010000000000000#01
intern-state     <  16> send packet: $qProcessInfo#dc
intern-state     <   7> read packet: $E01#a6
intern-state     <  16> send packet: $qProcessInfo#dc
intern-state     <   7> read packet: $E01#a6
intern-state     <  16> send packet: $qProcessInfo#dc
intern-state     <   7> read packet: $E01#a6
intern-state     <  26> send packet: $qStructuredDataPlugins#02
intern-state     <   6> read packet: $[]#b8
intern-state     <  26> send packet: $qMemoryRegionInfo:1004#d9
intern-state     <  41> read packet: $error:6e6f7420696d706c656d656e746564;#f7
intern-state     <  16> send packet: $jThreadsInfo#c1
intern-state     < 198> read packet: $[{"description":"mock accelerator thread stopped","name":"Mock Accelerator Thread","reason":"trace","registers":{"2":"0210000000000000","3":"0310000000000000"
,"4":"0410000000000000"}],"tid":1}]]#4a

```
mikolaj-pirog pushed a commit that referenced this pull request Jul 7, 2026
…long encodings (llvm#205907)

When a (signed or unsigned) LEB128 value is encoded with extra trailing
bytes that only carry zero- or sign-extension, the decode loop could
keep
running with the shift amount at 64 or beyond and then evaluate
`Slice << Shift`, which is undefined behavior for a 64-bit type.

The DWARF expression parser feeds attacker-controlled LEB128 operands
(such as `DW_OP_bregN` / `DW_OP_constu`) through
`DataExtractor::getULEB128` / `getSLEB128`, so the
`lldb-dwarf-expression-fuzzer` reaches this under UBSan.  The unsigned
case:

```
LEB128.h:152:20: runtime error: shift exponent 70 is too large for
64-bit type 'uint64_t' (aka 'unsigned long long')
    #0 llvm::decodeULEB128(...) LEB128.h:152
    #1 getLEB128<unsigned long long>(...) DataExtractor.cpp:227
    llvm#2 llvm::DataExtractor::getULEB128(...) DataExtractor.cpp:241
    llvm#3 llvm::DWARFExpression::Operation::extract(...) DWARFExpression.cpp:218
    llvm#7 lldb_private::DWARFExpression::Evaluate(...) DWARFExpression.cpp:1333
    llvm#9 LLVMFuzzerTestOneInput lldb-dwarf-expression-fuzzer.cpp:83
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior LEB128.h:152:20
```

and the signed case, reached the same way:

```
LEB128.h:190:20: runtime error: shift exponent 70 is too large for
64-bit type 'uint64_t' (aka 'unsigned long long')
    #0 llvm::decodeSLEB128(...) LEB128.h:190
    #1 getLEB128<long long>(...) DataExtractor.cpp:227
    llvm#2 llvm::DataExtractor::getSLEB128(...) DataExtractor.cpp:245
    llvm#3 llvm::DWARFExpression::Operation::extract(...) DWARFExpression.cpp:216
    llvm#7 lldb_private::DWARFExpression::Evaluate(...) DWARFExpression.cpp:1333
```

The existing range checks already guarantee that once `Shift` reaches 64
the remaining bytes are pure extension and contribute nothing to the
result, so skip the accumulating shift in that case.  Decoded values are
unchanged for all well-formed inputs.

Adds overlong-encoding regression cases to `LEB128Test`. Without the fix
the signed case is the UBSan diagnostic above in a sanitizer build, and
in a normal build the unsigned case also decodes to the wrong value (the
overlong `1` decodes as `11`).
RKSimon pushed a commit that referenced this pull request Aug 27, 2026
This PR optimizes the AArch64 backend for 128-bit integer squaring
(`u128 x * x`).

It updates the instruction selection logic to combine `(A + B) + B` into
`A + (B << 1)`. This allows the compiler to emit a single, optimal `add
... lsl #1` instruction instead of multiple separate `add` instructions.

A baseline test was added in the first commit, and the optimization is
provided in the second commit to clearly highlight the codegen
improvements.

Fixes llvm#213775
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