fallback: legalize: G_FPTOSI

fallback: legalize: G_FPTOSI_SAT s8,s16

Run:	explore-bc8218b282-20261015-075519
Kind:	fallback
Category:	legalize: G_FPTOSI_SAT s8,s16
Occurrences:	18 in 14 configs, 1 test files
Snippet from:	half-convert.ll @fcvt_w_s_sat_i8 via llvm-extract
Config:	`-mtriple=riscv32 -mattr=+d -target-abi=ilp32 -verify-machineinstrs`
Local check:	reproduces at bc8218b282
Compiler Explorer:	not uploaded (over --godbolt-limit or disabled)

Snippet:

; Function Attrs: nounwind
define signext i8 @fcvt_w_s_sat_i8(half %a) #0 {
start:
  %0 = tail call i8 @llvm.fptosi.sat.i8.f16(half %a)
  ret i8 %0
}

; Function Attrs: nocallback nocreateundeforpoison nofree nosync nounwind speculatable willreturn memory(none)
declare i8 @llvm.fptosi.sat.i8.f16(half) #1

attributes #0 = { nounwind }
attributes #1 = { nocallback nocreateundeforpoison nofree nosync nounwind speculatable willreturn memory(none) }

Reproduce:

llc -mtriple=riscv32 -mattr=+d -target-abi=ilp32 -verify-machineinstrs -global-isel -global-isel-abort=2 -pass-remarks-missed=gisel.* snippet.ll -o -
llc -mtriple=riscv32 -mattr=+d -target-abi=ilp32 -verify-machineinstrs -global-isel=0 snippet.ll -o -

Local llc output:

remark: <unknown>:0:0: unable to legalize instruction: %2:_(s8) = G_FPTOSI_SAT %0:_(s16) (in function: fcvt_w_s_sat_i8)
warning: Instruction selection used fallback path for fcvt_w_s_sat_i8

Occurrences (18):

Input	Function	Config
half-convert.ll	fcvt_w_s_sat_i8	`-mtriple=riscv32 -mattr=+d -target-abi=ilp32 -verify-machineinstrs`
half-convert.ll	fcvt_w_s_sat_i8	`-mtriple=riscv32 -mattr=+d -target-abi=ilp32d -verify-machineinstrs`
half-convert.ll	fcvt_w_s_sat_i8	`-mtriple=riscv32 -mattr=+d,+zfh -verify-machineinstrs -target-abi ilp32d`
half-convert.ll	fcvt_w_s_sat_i8	`-mtriple=riscv32 -mattr=+d,+zfhmin -verify-machineinstrs -target-abi ilp32d`
half-convert.ll	fcvt_w_s_sat_i8	`-mtriple=riscv32 -mattr=+zfh -verify-machineinstrs -target-abi ilp32f`
half-convert.ll	fcvt_w_s_sat_i8	`-mtriple=riscv32 -mattr=+zfhmin -verify-machineinstrs -target-abi ilp32f`
half-convert.ll	fcvt_w_s_sat_i8	`-mtriple=riscv32 -verify-machineinstrs`
half-convert.ll	fcvt_w_s_sat_i8	`-mtriple=riscv64 -mattr=+d -target-abi=lp64 -verify-machineinstrs`
half-convert.ll	fcvt_w_s_sat_i8	`-mtriple=riscv64 -mattr=+d -target-abi=lp64d -verify-machineinstrs`
half-convert.ll	fcvt_w_s_sat_i8	`-mtriple=riscv64 -mattr=+d,+zfh -verify-machineinstrs -target-abi lp64d`
half-convert.ll	fcvt_w_s_sat_i8	`-mtriple=riscv64 -mattr=+d,+zfhmin -verify-machineinstrs -target-abi lp64d`
half-convert.ll	fcvt_w_s_sat_i8	`-mtriple=riscv64 -mattr=+zfh -verify-machineinstrs -target-abi lp64f`
half-convert.ll	fcvt_w_s_sat_i8	`-mtriple=riscv64 -mattr=+zfhmin -verify-machineinstrs -target-abi lp64f`
half-convert.ll	fcvt_w_s_sat_i8	`-mtriple=riscv64 -verify-machineinstrs`
half-convert.01cca2c2c8.ll (mutant of half-convert.ll)	fcvt_w_s_sat_i8	`-mtriple=riscv64 -mattr=+d,+zfh -verify-machineinstrs -target-abi lp64d`
half-convert.3217f43d8b.ll (mutant of half-convert.ll)	fcvt_w_s_sat_i8	`-mtriple=riscv32 -mattr=+zfh -verify-machineinstrs -target-abi ilp32f`
half-convert.4c7ce119a7.ll (mutant of half-convert.ll)	fcvt_w_s_sat_i8	`-mtriple=riscv32 -mattr=+d,+zfh -verify-machineinstrs -target-abi ilp32d`
half-convert.c977b30c5a.ll (mutant of half-convert.ll)	fcvt_w_s_sat_i8	`-mtriple=riscv64 -mattr=+zfh -verify-machineinstrs -target-abi lp64f`

Generated 2026-10-15 08:05 UTC.