fallback: legalize: G_ASHR <2 x s16>

Run:	explore-bc8218b282-20261015-075519
Kind:	fallback
Category:	legalize: G_ASHR <2 x s16>
Occurrences:	2 in 1 configs, 1 test files
Snippet from:	rvp-simd-32.ll @test_psra_hs via llvm-extract
Config:	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
Local check:	reproduces at bc8218b282
Compiler Explorer:	not uploaded (over --godbolt-limit or disabled)

Snippet:

define <2 x i16> @test_psra_hs(<2 x i16> %a, i16 %shamt) {
  %insert = insertelement <2 x i16> poison, i16 %shamt, i32 0
  %b = shufflevector <2 x i16> %insert, <2 x i16> poison, <2 x i32> zeroinitializer
  %res = ashr <2 x i16> %a, %b
  ret <2 x i16> %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: %9:_(<2 x s16>) = G_ASHR %0:_, %8:_(<2 x s16>) (in function: test_psra_hs)
warning: Instruction selection used fallback path for test_psra_hs

Occurrences (2):

Input	Function	Config
rvp-simd-32.ll	test_psra_hs	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-32.ll	test_psra_hs_mask	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`

Generated 2026-10-15 08:05 UTC.