fallback: legalize: G_STRICT_FMA s64

Snippet:

; Function Attrs: nounwind strictfp
define double @fmadd_d(double %a, double %b, double %c) #0 {
  %1 = call double @llvm.experimental.constrained.fma.f64(double %a, double %b, double %c, metadata !"round.dynamic", metadata !"fpexcept.strict") #2
  ret double %1
}

; Function Attrs: nocallback nofree nosync nounwind strictfp willreturn memory(inaccessiblemem: readwrite)
declare double @llvm.experimental.constrained.fma.f64(double, double, double, metadata, metadata) #1

attributes #0 = { nounwind strictfp }
attributes #1 = { nocallback nofree nosync nounwind strictfp willreturn memory(inaccessiblemem: readwrite) }
attributes #2 = { strictfp }

Reproduce:

llc -mtriple=riscv32 -mattr=+d -verify-machineinstrs -disable-strictnode-mutation -target-abi=ilp32d -global-isel -global-isel-abort=2 -pass-remarks-missed=gisel.* snippet.ll -o -
llc -mtriple=riscv32 -mattr=+d -verify-machineinstrs -disable-strictnode-mutation -target-abi=ilp32d -global-isel=0 snippet.ll -o -

Local llc output:

remark: <unknown>:0:0: unable to legalize instruction: %3:_(s64) = G_STRICT_FMA %0:_, %1:_, %2:_ (in function: fmadd_d)
warning: Instruction selection used fallback path for fmadd_d

Occurrences (78) (first 50):

Generated 2026-10-15 08:05 UTC.