fallback: legalize: G_SHUFFLE_VECTOR <4 x s16>,<2 x s16>

Run:main-04ca53e65f-20261014-113325
Kind:fallback
Category:legalize: G_SHUFFLE_VECTOR <4 x s16>,<2 x s16>
Occurrences:1 in 1 configs, 1 test files
Snippet from:rvp-zip.ll @test_pzip_v4i16 via llvm-extract
Config:-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs
Local check:reproduces at 04ca53e65f
Compiler Explorer:not uploaded (over --godbolt-limit or disabled)

Snippet:

define <4 x i16> @test_pzip_v4i16(<2 x i16> %a, <2 x i16> %b) {
  %r = shufflevector <2 x i16> %a, <2 x i16> %b, <4 x i32> <i32 0, i32 2, i32 1, i32 3>
  ret <4 x i16> %r
}

Reproduce:

llc -mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs -global-isel -global-isel-abort=2 -pass-remarks-missed=gisel.* snippet.ll -o -
llc -mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs -global-isel=0 snippet.ll -o -

Local llc output:

remark: <unknown>:0:0: unable to legalize instruction: %6:_(<4 x s16>) = G_SHUFFLE_VECTOR %0:_(<2 x s16>), %1:_, shufflemask(0, 2, 1, 3) (in function: test_pzip_v4i16)
warning: Instruction selection used fallback path for test_pzip_v4i16

Occurrences (1):

InputFunctionConfig
rvp-zip.lltest_pzip_v4i16-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs

Generated 2026-10-15 08:05 UTC.