fallback: legalize: G_SHL <2 x s32>

Run:explore-04ca53e65f-20261014-114124
Kind:fallback
Category:legalize: G_SHL <2 x s32>
Occurrences:4 in 1 configs, 1 test files
Snippet from:rvp-simd-64.ll @test_pslli_w 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 <2 x i32> @test_pslli_w(<2 x i32> %a) {
  %res = shl <2 x i32> %a, splat (i32 2)
  ret <2 x i32> %res
}

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: %3:_(<2 x s32>) = G_SHL %0:_, %1:_(<2 x s32>) (in function: test_pslli_w)
warning: Instruction selection used fallback path for test_pslli_w

Occurrences (4):

InputFunctionConfig
rvp-simd-64.lltest_pslli_w-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs
rvp-simd-64.lltest_psll_ws-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs
rvp-simd-64.lltest_psll_ws_mask-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs
rvp-simd-64.lltest_psll_ws_vec_shamt-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs

Generated 2026-10-15 08:05 UTC.