fallback: legalize: G_UITOFP s16,s64

Run:main-04ca53e65f-20261014-113325
Kind:fallback
Category:legalize: G_UITOFP s16,s64
Occurrences:12 in 12 configs, 1 test files
Snippet from:half-convert.ll @fcvt_h_lu via llvm-extract
Config:-mtriple=riscv32 -mattr=+d -target-abi=ilp32 -verify-machineinstrs
Local check:reproduces at 04ca53e65f
Compiler Explorer:not uploaded (over --godbolt-limit or disabled)

Snippet:

; Function Attrs: nounwind
define half @fcvt_h_lu(i64 %a) #0 {
  %1 = uitofp i64 %a to half
  ret half %1
}

attributes #0 = { nounwind }

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: %3:_(s16) = G_UITOFP %0:_(s64) (in function: fcvt_h_lu)
warning: Instruction selection used fallback path for fcvt_h_lu

Occurrences (12):

InputFunctionConfig
half-convert.llfcvt_h_lu-mtriple=riscv32 -mattr=+d -target-abi=ilp32 -verify-machineinstrs
half-convert.llfcvt_h_lu-mtriple=riscv32 -mattr=+d -target-abi=ilp32d -verify-machineinstrs
half-convert.llfcvt_h_lu-mtriple=riscv32 -mattr=+d,+zfh -verify-machineinstrs -target-abi ilp32d
half-convert.llfcvt_h_lu-mtriple=riscv32 -mattr=+d,+zfhmin -verify-machineinstrs -target-abi ilp32d
half-convert.llfcvt_h_lu-mtriple=riscv32 -mattr=+zfh -verify-machineinstrs -target-abi ilp32f
half-convert.llfcvt_h_lu-mtriple=riscv32 -mattr=+zfhmin -verify-machineinstrs -target-abi ilp32f
half-convert.llfcvt_h_lu-mtriple=riscv32 -verify-machineinstrs
half-convert.llfcvt_h_lu-mtriple=riscv64 -mattr=+d -target-abi=lp64 -verify-machineinstrs
half-convert.llfcvt_h_lu-mtriple=riscv64 -mattr=+d -target-abi=lp64d -verify-machineinstrs
half-convert.llfcvt_h_lu-mtriple=riscv64 -mattr=+d,+zfhmin -verify-machineinstrs -target-abi lp64d
half-convert.llfcvt_h_lu-mtriple=riscv64 -mattr=+zfhmin -verify-machineinstrs -target-abi lp64f
half-convert.llfcvt_h_lu-mtriple=riscv64 -verify-machineinstrs

Generated 2026-10-15 08:05 UTC.