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

Run:	explore-bc8218b282-20261015-075519
Kind:	fallback
Category:	legalize: G_ICMP <8 x s1>,<8 x s8>
Occurrences:	14 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 bc8218b282
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 (14):

Input	Function	Config
rvp-simd-64.ll	test_eq_b	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.ll	test_ne_b	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.ll	test_nez_b	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.ll	test_slt_b	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.ll	test_sle_b	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.ll	test_sgt_b	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.ll	test_sge_b	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.ll	test_sgez_b	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.ll	test_ult_b	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.ll	test_ule_b	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.ll	test_ugt_b	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.ll	test_uge_b	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.02d9ee011d.ll (mutant of rvp-simd-64.ll)	test_ugt_b	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.a7ed24044c.ll (mutant of rvp-simd-64.ll)	test_sgez_b	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`

Generated 2026-10-15 08:05 UTC.