add test for codegen of SIMD vector from array repeat #151869

folkertdev · 2026-01-30T16:59:21Z

It appears that this issue was fixed silently in LLVM 19. The original codegen was terrible, but starting at LLVM 19 opt is able to generate good code.

https://llvm.godbolt.org/z/5vq8scP6q

cc @programmerjake

rustbot · 2026-01-30T16:59:27Z

r? @Mark-Simulacrum

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tests/codegen-llvm/simd/array-repeat.rs

rust-log-analyzer · 2026-01-30T18:29:52Z

The job pr-check-2 failed! Check out the build log: (web) (plain enhanced) (plain)

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##[group]Runner Image Provisioner
Hosted Compute Agent
Version: 20260123.484
Commit: 6bd6555ca37d84114959e1c76d2c01448ff61c5d
Build Date: 2026-01-23T19:41:17Z
Worker ID: {0ca236c6-d616-4458-9b19-d95f3a937a03}
Azure Region: westcentralus
##[endgroup]
##[group]Operating System
Ubuntu
24.04.3
LTS
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---
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap (line 72) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,RandomState>::new (line 264) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,RandomState>::from (line 1504) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,RandomState>::with_capacity (line 283) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::capacity (line 445) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::clear (line 819) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::contains_key (line 1220) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::drain (line 721) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::entry (line 959) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::extract_if (line 761) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::get (line 987) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::get_disjoint_mut (line 1119) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::get_disjoint_mut (line 1077) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::hasher (line 837) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::get_key_value (line 1017) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::get_disjoint_unchecked_mut (line 1162) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::get_mut (line 1247) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::insert (line 1280) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::into_iter (line 2053) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::into_keys (line 491) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::into_values (line 586) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::is_empty (line 698) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::iter (line 618) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::iter_mut (line 648) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::keys (line 461) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::len (line 681) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::remove (line 1339) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::reserve (line 870) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::remove_entry (line 1367) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::retain (line 792) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::shrink_to (line 937) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::shrink_to_fit (line 913) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::try_insert (line 1309) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::try_reserve (line 895) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S>::with_capacity_and_hasher (line 383) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::values (line 523) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S,A>::values_mut (line 552) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::HashMap<K,V,S>::with_hasher (line 351) ... ok
test library/std/src/collections/hash/map.rs - collections::hash::map::IntoValues (line 1877) ... ok
---
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,RandomState>::new (line 142) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,RandomState>::with_capacity (line 161) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::capacity (line 313) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,RandomState>::from (line 1180) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::clear (line 490) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::contains (line 758) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::drain (line 398) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::difference (line 630) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::entry (line 861) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::extract_if (line 434) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::get (line 783) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::get_or_insert (line 805) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::get_or_insert_with (line 829) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::hasher (line 508) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::insert (line 983) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::into_iter (line 1643) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::is_disjoint (line 903) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::intersection (line 697) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::is_empty (line 375) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::iter (line 329) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::is_superset (line 951) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::is_subset (line 929) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::len (line 357) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::reserve (line 541) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::remove (line 1030) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::replace (line 1004) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::retain (line 465) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::shrink_to (line 607) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::shrink_to_fit (line 584) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::symmetric_difference (line 660) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::take (line 1058) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::try_reserve (line 567) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S,A>::union (line 726) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S>::with_capacity_and_hasher (line 255) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::HashSet<T,S>::with_hasher (line 223) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::Intersection (line 1507) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::IntoIter (line 1422) ... ok
test library/std/src/collections/hash/set.rs - collections::hash::set::Iter (line 1392) ... ok
---

---- [codegen] tests/codegen-llvm/simd/array-repeat.rs stdout ----
------FileCheck stdout------------------------------

------FileCheck stderr------------------------------
/checkout/tests/codegen-llvm/simd/array-repeat.rs:16:17: error: CHECK-NEXT: expected string not found in input
 // CHECK-NEXT: %0 = insertelement <8 x i16> poison, i16 %v, i64 0
                ^
/checkout/obj/build/x86_64-unknown-linux-gnu/test/codegen-llvm/simd/array-repeat/array-repeat.ll:8:6: note: scanning from here
start:
     ^
/checkout/obj/build/x86_64-unknown-linux-gnu/test/codegen-llvm/simd/array-repeat/array-repeat.ll:10:23: note: possible intended match here
 %_5.sroa.4.0.p.sroa_idx = getelementptr inbounds nuw i8, ptr %p, i32 2
                      ^

Input file: /checkout/obj/build/x86_64-unknown-linux-gnu/test/codegen-llvm/simd/array-repeat/array-repeat.ll
Check file: /checkout/tests/codegen-llvm/simd/array-repeat.rs

-dump-input=help explains the following input dump.

Input was:
<<<<<<
           1: ; ModuleID = 'array_repeat.57d4eb84faba7a8b-cgu.0' 
           2: source_filename = "array_repeat.57d4eb84faba7a8b-cgu.0" 
           3: target datalayout = "e-m:e-p:32:32-p10:8:8-p20:8:8-i64:64-i128:128-n32:64-S128-ni:1:10:20" 
           4: target triple = "wasm32-unknown-wasip1" 
           5:  
           6: ; Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(argmem: write) 
           7: define dso_local void @foo(i16 noundef %v, ptr noalias noundef writeonly align 1 captures(none) dereferenceable(16) initializes((0, 16)) %p) unnamed_addr #0 { 
           8: start: 
next:16'0          X~ error: no match found
           9:  store i16 %v, ptr %p, align 1 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          10:  %_5.sroa.4.0.p.sroa_idx = getelementptr inbounds nuw i8, ptr %p, i32 2 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
next:16'1                           ?                                                  possible intended match
          11:  store i16 %v, ptr %_5.sroa.4.0.p.sroa_idx, align 1 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          12:  %_5.sroa.5.0.p.sroa_idx = getelementptr inbounds nuw i8, ptr %p, i32 4 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          13:  store i16 %v, ptr %_5.sroa.5.0.p.sroa_idx, align 1 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          14:  %_5.sroa.6.0.p.sroa_idx = getelementptr inbounds nuw i8, ptr %p, i32 6 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          15:  store i16 %v, ptr %_5.sroa.6.0.p.sroa_idx, align 1 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          16:  %_5.sroa.7.0.p.sroa_idx = getelementptr inbounds nuw i8, ptr %p, i32 8 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          17:  store i16 %v, ptr %_5.sroa.7.0.p.sroa_idx, align 1 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          18:  %_5.sroa.8.0.p.sroa_idx = getelementptr inbounds nuw i8, ptr %p, i32 10 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          19:  store i16 %v, ptr %_5.sroa.8.0.p.sroa_idx, align 1 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          20:  %_5.sroa.9.0.p.sroa_idx = getelementptr inbounds nuw i8, ptr %p, i32 12 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          21:  store i16 %v, ptr %_5.sroa.9.0.p.sroa_idx, align 1 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          22:  %_5.sroa.10.0.p.sroa_idx = getelementptr inbounds nuw i8, ptr %p, i32 14 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          23:  store i16 %v, ptr %_5.sroa.10.0.p.sroa_idx, align 1 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          24:  ret void 
next:16'0     ~~~~~~~~~~
          25: } 
next:16'0     ~~
          26:  
next:16'0     ~
          27: attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(argmem: write) "target-cpu"="generic" } 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          28:  
next:16'0     ~
          29: !llvm.ident = !{!0} 
next:16'0     ~~~~~~~~~~~~~~~~~~~~
          30:  
next:16'0     ~
          31: !0 = !{!"rustc version 1.95.0-nightly (58a5550ab 2026-01-30)"} 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>>>>>

------------------------------------------

error: verification with 'FileCheck' failed
status: exit status: 1
command: "/checkout/obj/build/x86_64-unknown-linux-gnu/ci-llvm/bin/FileCheck" "--input-file" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/codegen-llvm/simd/array-repeat/array-repeat.ll" "/checkout/tests/codegen-llvm/simd/array-repeat.rs" "--check-prefix=CHECK" "--allow-unused-prefixes" "--dump-input-context" "100"
stdout: none
--- stderr -------------------------------
/checkout/tests/codegen-llvm/simd/array-repeat.rs:16:17: error: CHECK-NEXT: expected string not found in input
 // CHECK-NEXT: %0 = insertelement <8 x i16> poison, i16 %v, i64 0
                ^
/checkout/obj/build/x86_64-unknown-linux-gnu/test/codegen-llvm/simd/array-repeat/array-repeat.ll:8:6: note: scanning from here
start:
     ^
/checkout/obj/build/x86_64-unknown-linux-gnu/test/codegen-llvm/simd/array-repeat/array-repeat.ll:10:23: note: possible intended match here
 %_5.sroa.4.0.p.sroa_idx = getelementptr inbounds nuw i8, ptr %p, i32 2
                      ^

Input file: /checkout/obj/build/x86_64-unknown-linux-gnu/test/codegen-llvm/simd/array-repeat/array-repeat.ll
Check file: /checkout/tests/codegen-llvm/simd/array-repeat.rs

-dump-input=help explains the following input dump.

Input was:
<<<<<<
           1: ; ModuleID = 'array_repeat.57d4eb84faba7a8b-cgu.0' 
           2: source_filename = "array_repeat.57d4eb84faba7a8b-cgu.0" 
           3: target datalayout = "e-m:e-p:32:32-p10:8:8-p20:8:8-i64:64-i128:128-n32:64-S128-ni:1:10:20" 
           4: target triple = "wasm32-unknown-wasip1" 
           5:  
           6: ; Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(argmem: write) 
           7: define dso_local void @foo(i16 noundef %v, ptr noalias noundef writeonly align 1 captures(none) dereferenceable(16) initializes((0, 16)) %p) unnamed_addr #0 { 
           8: start: 
next:16'0          X~ error: no match found
           9:  store i16 %v, ptr %p, align 1 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          10:  %_5.sroa.4.0.p.sroa_idx = getelementptr inbounds nuw i8, ptr %p, i32 2 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
next:16'1                           ?                                                  possible intended match
          11:  store i16 %v, ptr %_5.sroa.4.0.p.sroa_idx, align 1 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          12:  %_5.sroa.5.0.p.sroa_idx = getelementptr inbounds nuw i8, ptr %p, i32 4 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          13:  store i16 %v, ptr %_5.sroa.5.0.p.sroa_idx, align 1 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          14:  %_5.sroa.6.0.p.sroa_idx = getelementptr inbounds nuw i8, ptr %p, i32 6 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          15:  store i16 %v, ptr %_5.sroa.6.0.p.sroa_idx, align 1 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          16:  %_5.sroa.7.0.p.sroa_idx = getelementptr inbounds nuw i8, ptr %p, i32 8 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          17:  store i16 %v, ptr %_5.sroa.7.0.p.sroa_idx, align 1 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          18:  %_5.sroa.8.0.p.sroa_idx = getelementptr inbounds nuw i8, ptr %p, i32 10 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          19:  store i16 %v, ptr %_5.sroa.8.0.p.sroa_idx, align 1 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          20:  %_5.sroa.9.0.p.sroa_idx = getelementptr inbounds nuw i8, ptr %p, i32 12 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          21:  store i16 %v, ptr %_5.sroa.9.0.p.sroa_idx, align 1 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          22:  %_5.sroa.10.0.p.sroa_idx = getelementptr inbounds nuw i8, ptr %p, i32 14 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          23:  store i16 %v, ptr %_5.sroa.10.0.p.sroa_idx, align 1 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          24:  ret void 
next:16'0     ~~~~~~~~~~
          25: } 
next:16'0     ~~
          26:  
next:16'0     ~
          27: attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(argmem: write) "target-cpu"="generic" } 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          28:  
next:16'0     ~
          29: !llvm.ident = !{!0} 
next:16'0     ~~~~~~~~~~~~~~~~~~~~
          30:  
next:16'0     ~
          31: !0 = !{!"rustc version 1.95.0-nightly (58a5550ab 2026-01-30)"} 
next:16'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>>>>>
------------------------------------------

---- [codegen] tests/codegen-llvm/simd/array-repeat.rs stdout end ----

folkertdev · 2026-01-30T18:46:02Z

Hmm, it is fixed on x86_64 and aarch64, but not for other targets where vector types require a target feature.

for s390x it only optimizes when the vector target feature is available
for wasm32 even with +simd128 it does not optimize (should just be a splat I think?)

Do we consider that fixed?

folkertdev · 2026-01-30T19:08:15Z

I did file llvm/llvm-project#178940 for the wasm issue, cc @nikic

workingjubilee · 2026-01-30T21:33:19Z

For s390x without +vector, it probably comes from type legalization: LLVM, if it can't fit a type or operation with that type to a series of machine operations, will, during... lowering to SelectionDAG, I think?... "scalarize" the operations into operations on a valid type.

folkertdev · 2026-01-30T21:41:33Z

I'm a bit out of my depth here, but I would expect the transformation to a vector splat to happen much earlier than that. You're right that it does appear use information about what types are legal for the current target though.

folkertdev added the A-SIMD Area: SIMD (Single Instruction Multiple Data) label Jan 30, 2026

rustbot assigned Mark-Simulacrum Jan 30, 2026

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Jan 30, 2026

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add test for simd from array repeat codegen

1369f03

folkertdev force-pushed the simd-array-repeat branch from 2423398 to 1369f03 Compare January 30, 2026 17:49

programmerjake reviewed Jan 30, 2026

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add test for codegen of SIMD vector from array repeat #151869

add test for codegen of SIMD vector from array repeat #151869

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add test for codegen of SIMD vector from array repeat #151869

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add test for codegen of SIMD vector from array repeat #151869

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folkertdev commented Jan 30, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

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rust-log-analyzer commented Jan 30, 2026

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folkertdev commented Jan 30, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

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workingjubilee commented Jan 30, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

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folkertdev commented Jan 30, 2026 •

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folkertdev commented Jan 30, 2026 •

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workingjubilee commented Jan 30, 2026 •

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