fallback: legalize: G_SMULFIX s64

Run:main-04ca53e65f-20261014-105623
Kind:fallback
Category:legalize: G_SMULFIX s64
Occurrences:4 in 1 configs, 1 test files
Snippet from:addcarry.ll @addcarry via llvm-extract
Config:-mtriple=riscv32 -mattr=+m
Local check:reproduces at 04ca53e65f
Compiler Explorer:not uploaded (over --godbolt-limit or disabled)

Snippet:

; Function Attrs: nounwind
define i64 @addcarry(i64 %x, i64 %y) #0 {
  %tmp = call i64 @llvm.smul.fix.i64(i64 %x, i64 %y, i32 2)
  ret i64 %tmp
}

; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare i64 @llvm.smul.fix.i64(i64, i64, i32 immarg) #1

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

Reproduce:

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

Local llc output:

remark: <unknown>:0:0: unable to legalize instruction: %6:_(s64) = G_SMULFIX %0:_, %1:_, 2 (in function: addcarry)
warning: Instruction selection used fallback path for addcarry

Occurrences (4):

InputFunctionConfig
addcarry.lladdcarry-mtriple=riscv32 -mattr=+m
addcarry.4a00fc34d5.ll (mutant of addcarry.ll)addcarry-mtriple=riscv32 -mattr=+m
addcarry.8a12b6c618.ll (mutant of addcarry.ll)addcarry-mtriple=riscv32 -mattr=+m
addcarry.bb80fcc081.ll (mutant of addcarry.ll)addcarry-mtriple=riscv32 -mattr=+m

Generated 2026-10-15 08:05 UTC.