fallback: legalize: G_ZEXTLOAD s128,p0,s64

Run:	main-bc8218b282-20261015-074651
Kind:	fallback
Category:	legalize: G_ZEXTLOAD s128,p0,s64
Occurrences:	12 in 5 configs, 4 test files
Snippet from:	condops.ll @single_bit3 via llvm-extract
Config:	`-mtriple=riscv32 -target-abi=ilp32f -mattr=+f,+zbs`
Local check:	reproduces at bc8218b282
Compiler Explorer:	not uploaded (over --godbolt-limit or disabled)

Snippet:

define i64 @single_bit3(i80 %x, i64 %y) {
entry:
  %and = and i80 %x, 18446744073709551616
  %tobool.not = icmp eq i80 %and, 0
  %cond = select i1 %tobool.not, i64 0, i64 %y
  ret i64 %cond
}

Reproduce:

llc -mtriple=riscv32 -target-abi=ilp32f -mattr=+f,+zbs -global-isel -global-isel-abort=2 -pass-remarks-missed=gisel.* snippet.ll -o -
llc -mtriple=riscv32 -target-abi=ilp32f -mattr=+f,+zbs -global-isel=0 snippet.ll -o -

Local llc output:

remark: <unknown>:0:0: unable to legalize instruction: %58:_(s128) = G_ZEXTLOAD %2:_(p0) :: (load (s64)) (in function: single_bit3)
warning: Instruction selection used fallback path for single_bit3

Occurrences (12):

Input	Function	Config
condops.ll	single_bit3	`-mtriple=riscv32 -target-abi=ilp32f -mattr=+f,+zbs`
condops.ll	single_bit3	`-mtriple=riscv32 -target-abi=ilp32f -mattr=+f,+zbs,+zicond`
pr56110.ll	foo_set	`-mtriple=riscv32`
pr56110.ll	foo_set	`-mtriple=riscv32 -mattr=+unaligned-scalar-mem`
smulh.ll	smulh_i96	`-mtriple=riscv32 -mattr=+m`
umulh.ll	umulh_i96	`-mtriple=riscv32 -mattr=+m`
pr56110.17499dd113.ll (mutant of pr56110.ll)	foo_set	`-mtriple=riscv32`
pr56110.77b3553171.ll (mutant of pr56110.ll)	foo_set	`-mtriple=riscv32`
pr56110.8b717a5cd6.ll (mutant of pr56110.ll)	foo_set	`-mtriple=riscv32 -mattr=+unaligned-scalar-mem`
pr56110.c36b6da4b2.ll (mutant of pr56110.ll)	foo_set	`-mtriple=riscv32 -mattr=+unaligned-scalar-mem`
pr56110.cbab47bc09.ll (mutant of pr56110.ll)	foo_set	`-mtriple=riscv32`
pr56110.d7f50fe739.ll (mutant of pr56110.ll)	foo_set	`-mtriple=riscv32 -mattr=+unaligned-scalar-mem`

Generated 2026-10-15 08:05 UTC.