fallback: legalize: G_ICMP <8 x s1>,<8 x s8>

Run:explore-04ca53e65f-20261014-114124
Kind:fallback
Category:legalize: G_ICMP <8 x s1>,<8 x s8>
Occurrences:12 in 1 configs, 1 test files
Snippet from:rvp-simd-64.ll @test_eq_b 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 <8 x i8> @test_eq_b(<8 x i8> %a, <8 x i8> %b) {
  %cmp = icmp eq <8 x i8> %a, %b
  %res = sext <8 x i1> %cmp to <8 x i8>
  ret <8 x i8> %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: %2:_(<8 x s1>) = G_ICMP intpred(eq), %0:_(<8 x s8>), %1:_ (in function: test_eq_b)
warning: Instruction selection used fallback path for test_eq_b

Occurrences (12):

InputFunctionConfig
rvp-simd-64.lltest_eq_b-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs
rvp-simd-64.lltest_ne_b-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs
rvp-simd-64.lltest_nez_b-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs
rvp-simd-64.lltest_slt_b-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs
rvp-simd-64.lltest_sle_b-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs
rvp-simd-64.lltest_sgt_b-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs
rvp-simd-64.lltest_sge_b-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs
rvp-simd-64.lltest_sgez_b-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs
rvp-simd-64.lltest_ult_b-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs
rvp-simd-64.lltest_ule_b-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs
rvp-simd-64.lltest_ugt_b-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs
rvp-simd-64.lltest_uge_b-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs

Generated 2026-10-15 08:05 UTC.