fallback: legalize: G_FFREXP s64,s32

Run:	explore-04ca53e65f-20261014-114124
Kind:	fallback
Category:	legalize: G_FFREXP s64,s32
Occurrences:	24 in 6 configs, 2 test files
Snippet from:	double-intrinsics.ll @frexp_double via llvm-extract
Config:	`-mtriple=riscv32 -mattr=+d -verify-machineinstrs -target-abi=ilp32d`
Local check:	reproduces at 04ca53e65f
Compiler Explorer:	not uploaded (over --godbolt-limit or disabled)

Snippet:

; Function Attrs: nounwind
define { double, i32 } @frexp_double(double %x) #0 {
  %a = call { double, i32 } @llvm.frexp.f64.i32(double %x)
  ret { double, i32 } %a
}

; Function Attrs: nocallback nocreateundeforpoison nofree nosync nounwind speculatable willreturn memory(none)
declare { double, i32 } @llvm.frexp.f64.i32(double) #1

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

Reproduce:

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

Local llc output:

remark: <unknown>:0:0: unable to legalize instruction: %1:_(s64), %2:_(s32) = G_FFREXP %0:_ (in function: frexp_double)
warning: Instruction selection used fallback path for frexp_double

Occurrences (24):

Input	Function	Config
double-intrinsics.ll	frexp_double	`-mtriple=riscv32 -mattr=+d -verify-machineinstrs -target-abi=ilp32d`
double-intrinsics.ll	frexp_double	`-mtriple=riscv32 -mattr=+zdinx -verify-machineinstrs -target-abi=ilp32`
double-intrinsics.ll	frexp_double	`-mtriple=riscv32 -verify-machineinstrs`
double-intrinsics.ll	frexp_double	`-mtriple=riscv64 -mattr=+d -verify-machineinstrs -target-abi=lp64d`
double-intrinsics.ll	frexp_double	`-mtriple=riscv64 -mattr=+zdinx -verify-machineinstrs -target-abi=lp64`
double-intrinsics.ll	frexp_double	`-mtriple=riscv64 -verify-machineinstrs`
llvm.frexp.ll	test_frexp_f64_i32	`-mtriple=riscv32 -mattr=+d -verify-machineinstrs -target-abi=ilp32d`
llvm.frexp.ll	test_frexp_f64_i32_only_use_fract	`-mtriple=riscv32 -mattr=+d -verify-machineinstrs -target-abi=ilp32d`
llvm.frexp.ll	test_frexp_f64_i32_only_use_exp	`-mtriple=riscv32 -mattr=+d -verify-machineinstrs -target-abi=ilp32d`
llvm.frexp.ll	test_frexp_f64_i32	`-mtriple=riscv32 -mattr=+zdinx -verify-machineinstrs -target-abi=ilp32`
llvm.frexp.ll	test_frexp_f64_i32_only_use_fract	`-mtriple=riscv32 -mattr=+zdinx -verify-machineinstrs -target-abi=ilp32`
llvm.frexp.ll	test_frexp_f64_i32_only_use_exp	`-mtriple=riscv32 -mattr=+zdinx -verify-machineinstrs -target-abi=ilp32`
llvm.frexp.ll	test_frexp_f64_i32	`-mtriple=riscv32 -verify-machineinstrs`
llvm.frexp.ll	test_frexp_f64_i32_only_use_fract	`-mtriple=riscv32 -verify-machineinstrs`
llvm.frexp.ll	test_frexp_f64_i32_only_use_exp	`-mtriple=riscv32 -verify-machineinstrs`
llvm.frexp.ll	test_frexp_f64_i32	`-mtriple=riscv64 -mattr=+d -verify-machineinstrs -target-abi=lp64d`
llvm.frexp.ll	test_frexp_f64_i32_only_use_fract	`-mtriple=riscv64 -mattr=+d -verify-machineinstrs -target-abi=lp64d`
llvm.frexp.ll	test_frexp_f64_i32_only_use_exp	`-mtriple=riscv64 -mattr=+d -verify-machineinstrs -target-abi=lp64d`
llvm.frexp.ll	test_frexp_f64_i32	`-mtriple=riscv64 -mattr=+zdinx -verify-machineinstrs -target-abi=lp64`
llvm.frexp.ll	test_frexp_f64_i32_only_use_fract	`-mtriple=riscv64 -mattr=+zdinx -verify-machineinstrs -target-abi=lp64`
llvm.frexp.ll	test_frexp_f64_i32_only_use_exp	`-mtriple=riscv64 -mattr=+zdinx -verify-machineinstrs -target-abi=lp64`
llvm.frexp.ll	test_frexp_f64_i32	`-mtriple=riscv64 -verify-machineinstrs`
llvm.frexp.ll	test_frexp_f64_i32_only_use_fract	`-mtriple=riscv64 -verify-machineinstrs`
llvm.frexp.ll	test_frexp_f64_i32_only_use_exp	`-mtriple=riscv64 -verify-machineinstrs`

Generated 2026-10-15 08:05 UTC.