fallback: legalize: G_FSUB s128

Run:main-bc8218b282-20261015-074651
Kind:fallback
Category:legalize: G_FSUB s128
Occurrences:1 in 1 configs, 1 test files
Snippet from:musttail-indirect-args.ll @caller_musttail_both_computed via llvm-extract
Config:-mtriple=riscv32
Local check:reproduces at bc8218b282
Compiler Explorer:not uploaded (over --godbolt-limit or disabled)

Snippet:

declare i32 @callee_musttail_two_indirect(fp128, fp128)

; Function Attrs: nounwind
define i32 @caller_musttail_both_computed(fp128 %a, fp128 %b) #0 {
  %sum = fadd fp128 %a, %b
  %diff = fsub fp128 %a, %b
  %r = musttail call i32 @callee_musttail_two_indirect(fp128 %sum, fp128 %diff)
  ret i32 %r
}

attributes #0 = { nounwind }

Reproduce:

llc -mtriple=riscv32 -global-isel -global-isel-abort=2 -pass-remarks-missed=gisel.* snippet.ll -o -
llc -mtriple=riscv32 -global-isel=0 snippet.ll -o -

Local llc output:

remark: <unknown>:0:0: unable to legalize instruction: %5:_(s128) = G_FSUB %0:_, %1:_ (in function: caller_musttail_both_computed)
warning: Instruction selection used fallback path for caller_musttail_both_computed

Occurrences (1):

InputFunctionConfig
musttail-indirect-args.llcaller_musttail_both_computed-mtriple=riscv32

Generated 2026-10-15 08:05 UTC.