fallback: legalize: G

fallback: legalize: G_ADD <8 x s8>

Run:	explore-bc8218b282-20261015-075519
Kind:	fallback
Category:	legalize: G_ADD <8 x s8>
Occurrences:	41 in 22 configs, 13 test files
Snippet from:	rvp-simd-64.ll @test_padd_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_padd_b(<8 x i8> %a, <8 x i8> %b) {
  %res = add <8 x i8> %a, %b
  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 s8>) = G_ADD %0:_, %1:_ (in function: test_padd_b)
warning: Instruction selection used fallback path for test_padd_b

Occurrences (41):

Input	Function	Config
calling-conv-p-ext-vector.ll	test_cc_v8i8	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.ll	test_padd_b	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.ll	test_paaddu_b	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.ll	test_padd_bs_splat_lhs	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
rvp-simd-64.ll	test_padd_bs_splat_rhs	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
atomic-rmw-discard.29d59056ac.ll (mutant of atomic-rmw-discard.ll)	amomaxu_w_discard	`-O3 -mtriple=riscv32 -mattr=+a -verify-machineinstrs`
atomic-rmw-discard.9a35dedd62.ll (mutant of atomic-rmw-discard.ll)	amomaxu_w_discard	`-O3 -mtriple=riscv64 -mattr=+a -verify-machineinstrs`
calling-conv-p-ext-vector.ae7acf31eb.ll (mutant of calling-conv-p-ext-vector.ll)	test_cc_v8i8	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
clmul.4ac56ca0e7.ll (mutant of clmul.ll)	commutative_clmul_i8	`-mtriple=riscv64 -mattr=+m,+zbc -verify-machineinstrs`
clmul.5da9d2339f.ll (mutant of clmul.ll)	commutative_clmul_i8	`-mtriple=riscv32 -verify-machineinstrs`
clmul.6244fbdae0.ll (mutant of clmul.ll)	commutative_clmul_i8	`-mtriple=riscv64 -mattr=+m,+zbs -verify-machineinstrs`
clmul.638d009dfb.ll (mutant of clmul.ll)	commutative_clmul_i8	`-mtriple=riscv64 -mattr=+m,+zvbc -verify-machineinstrs`
clmul.6e2f35ab64.ll (mutant of clmul.ll)	commutative_clmul_i8	`-mtriple=riscv64 -mattr=+m -verify-machineinstrs`
clmul.7960b30cc2.ll (mutant of clmul.ll)	commutative_clmul_i8	`-mtriple=riscv32 -mattr=+m,+zbs -verify-machineinstrs`
clmul.7b948e8269.ll (mutant of clmul.ll)	commutative_clmul_i8	`-mtriple=riscv32 -mattr=+m,+zvbc -verify-machineinstrs`
clmul.ae0fc6b5df.ll (mutant of clmul.ll)	commutative_clmul_i8	`-mtriple=riscv64 -verify-machineinstrs`
clmul.dc79bff085.ll (mutant of clmul.ll)	commutative_clmul_i8	`-mtriple=riscv32 -mattr=+m -verify-machineinstrs`
clmul.e4193046d9.ll (mutant of clmul.ll)	commutative_clmul_i8	`-mtriple=riscv32 -mattr=+m,+zbc -verify-machineinstrs`
div-pow2.34903d600a.ll (mutant of div-pow2.ll)	sdiv64_pow2_4096	`-mtriple=riscv64 -verify-machineinstrs`
div-pow2.dc63464d30.ll (mutant of div-pow2.ll)	sdiv64_pow2_4096	`-mtriple=riscv32 -verify-machineinstrs`
half-zfa.147c6fbb3c.ll (mutant of half-zfa.ll)	fcmp_ueq_q	`-mtriple=riscv32 -target-abi ilp32f -mattr=+zfa,+zfhmin`
half-zfa.2480c66825.ll (mutant of half-zfa.ll)	fcmp_ueq_q	`-mtriple=riscv32 -target-abi ilp32f -mattr=+zfa,+zfh`
half-zfa.32350fa86f.ll (mutant of half-zfa.ll)	fcmp_ueq_q	`-mtriple=riscv64 -target-abi lp64f -mattr=+zfa,+zfhmin`
half-zfa.8746b07552.ll (mutant of half-zfa.ll)	fcmp_ueq_q	`-mtriple=riscv64 -target-abi lp64f -mattr=+zfa,+zfh`
orc-b-patterns.1259d845af.ll (mutant of orc-b-patterns.ll)	orc_b_i32_sub_shl8x_x_b1_not_used	`-mtriple=riscv64 -verify-machineinstrs`
orc-b-patterns.9a08c9787d.ll (mutant of orc-b-patterns.ll)	orc_b_i32_sub_shl8x_x_b1_not_used	`-mtriple=riscv64 -mattr=+zbb -verify-machineinstrs`
orc-b-patterns.e382d96685.ll (mutant of orc-b-patterns.ll)	orc_b_i32_sub_shl8x_x_b1_not_used	`-mtriple=riscv32 -verify-machineinstrs`
orc-b-patterns.f926dbceb7.ll (mutant of orc-b-patterns.ll)	orc_b_i32_sub_shl8x_x_b1_not_used	`-mtriple=riscv32 -mattr=+zbb -verify-machineinstrs`
rem.26f6084e6c.ll (mutant of rem.ll)	srem8	`-mtriple=riscv32 -verify-machineinstrs`
rem.61033975a9.ll (mutant of rem.ll)	srem8	`-mtriple=riscv64 -verify-machineinstrs`
rem.9b728a995d.ll (mutant of rem.ll)	srem8	`-mtriple=riscv64 -mattr=+m -verify-machineinstrs`
rem.d8fb904dbc.ll (mutant of rem.ll)	srem8	`-mtriple=riscv32 -mattr=+m -verify-machineinstrs`
rvp-zip.14d6f1ac8b.ll (mutant of rvp-zip.ll)	test_unzip16p_v4i16_partial_poison	`-mtriple=riscv64 -mattr=+experimental-p,+m,+zbb -verify-machineinstrs`
shifts.6f9ead363b.ll (mutant of shifts.ll)	ashr64_shamt32	`-mtriple=riscv32 -verify-machineinstrs`
shifts.acc968b0a1.ll (mutant of shifts.ll)	ashr64_shamt32	`-mtriple=riscv64 -verify-machineinstrs`
shlimm-addimm.3e4bb5d192.ll (mutant of shlimm-addimm.ll)	shl5_sub47968_a	`-mtriple=riscv64 -verify-machineinstrs`
shlimm-addimm.b603cfa1bc.ll (mutant of shlimm-addimm.ll)	shl5_sub47968_a	`-mtriple=riscv32 -verify-machineinstrs`
xcvmac.3ce4698076.ll (mutant of xcvmac.ll)	test.macsN	`-mtriple=riscv32 -mattr=+m -mattr=+xcvmac -verify-machineinstrs`
xqcibm-insert.8392cb5af7.ll (mutant of xqcibm-insert.ll)	test7	`-mtriple=riscv32 -mattr=+xqcibm,+zbs -verify-machineinstrs`
xqcibm-insert.9f457d1332.ll (mutant of xqcibm-insert.ll)	test7	`-mtriple=riscv32 -mattr=+xqcibm -verify-machineinstrs`
xqcibm-insert.eaf1a9980e.ll (mutant of xqcibm-insert.ll)	test7	`-mtriple=riscv32 -verify-machineinstrs`

Generated 2026-10-15 08:05 UTC.