fallback: translate: call llvm.experimental.constrained.atan2.f32

Run:	explore-04ca53e65f-20261014-114124
Kind:	fallback
Category:	translate: call llvm.experimental.constrained.atan2.f32
Occurrences:	12 in 6 configs, 1 test files
Snippet from:	float-intrinsics-strict.ll @atan2_f32 via llvm-extract
Config:	`-mtriple=riscv32 -mattr=+f -verify-machineinstrs -disable-strictnode-mutation -target-abi=ilp32f`
Local check:	reproduces at 04ca53e65f
Compiler Explorer:	not uploaded (over --godbolt-limit or disabled)

Snippet:

; Function Attrs: nounwind strictfp
define float @atan2_f32(float %a, float %b) #0 {
  %1 = call float @llvm.experimental.constrained.atan2.f32(float %a, float %b, metadata !"round.dynamic", metadata !"fpexcept.strict") #2
  ret float %1
}

; Function Attrs: nocallback nofree nosync nounwind strictfp willreturn memory(inaccessiblemem: readwrite)
declare float @llvm.experimental.constrained.atan2.f32(float, float, 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=+f -verify-machineinstrs -disable-strictnode-mutation -target-abi=ilp32f -global-isel -global-isel-abort=2 -pass-remarks-missed=gisel.* snippet.ll -o -
llc -mtriple=riscv32 -mattr=+f -verify-machineinstrs -disable-strictnode-mutation -target-abi=ilp32f -global-isel=0 snippet.ll -o -

Local llc output:

remark: <unknown>:0:0: unable to translate instruction: call llvm.experimental.constrained.atan2.f32: '  %1 = call float @llvm.experimental.constrained.atan2.f32(float %a, float %b, metadata !"round.dynamic", metadata !"fpexcept.strict") #2' (in function: atan2_f32)
warning: Instruction selection used fallback path for atan2_f32

Occurrences (12):

Input	Function	Config
float-intrinsics-strict.ll	atan2_f32	`-mtriple=riscv32 -mattr=+f -verify-machineinstrs -disable-strictnode-mutation -target-abi=ilp32f`
float-intrinsics-strict.ll	atan2_f32	`-mtriple=riscv32 -mattr=+zfinx -verify-machineinstrs -disable-strictnode-mutation -target-abi=ilp32`
float-intrinsics-strict.ll	atan2_f32	`-mtriple=riscv32 -verify-machineinstrs -disable-strictnode-mutation`
float-intrinsics-strict.ll	atan2_f32	`-mtriple=riscv64 -mattr=+f -verify-machineinstrs -disable-strictnode-mutation -target-abi=lp64f`
float-intrinsics-strict.ll	atan2_f32	`-mtriple=riscv64 -mattr=+zfinx -verify-machineinstrs -disable-strictnode-mutation -target-abi=lp64`
float-intrinsics-strict.ll	atan2_f32	`-mtriple=riscv64 -verify-machineinstrs -disable-strictnode-mutation`
float-intrinsics-strict.0b77f72988.ll (mutant of float-intrinsics-strict.ll)	atan2_f32	`-mtriple=riscv64 -verify-machineinstrs -disable-strictnode-mutation`
float-intrinsics-strict.2540bbb49c.ll (mutant of float-intrinsics-strict.ll)	atan2_f32	`-mtriple=riscv32 -mattr=+f -verify-machineinstrs -disable-strictnode-mutation -target-abi=ilp32f`
float-intrinsics-strict.2cbac19acd.ll (mutant of float-intrinsics-strict.ll)	atan2_f32	`-mtriple=riscv64 -mattr=+f -verify-machineinstrs -disable-strictnode-mutation -target-abi=lp64f`
float-intrinsics-strict.2fdc88be53.ll (mutant of float-intrinsics-strict.ll)	atan2_f32	`-mtriple=riscv32 -verify-machineinstrs -disable-strictnode-mutation`
float-intrinsics-strict.93ec3beccb.ll (mutant of float-intrinsics-strict.ll)	atan2_f32	`-mtriple=riscv32 -mattr=+zfinx -verify-machineinstrs -disable-strictnode-mutation -target-abi=ilp32`
float-intrinsics-strict.b1576653bc.ll (mutant of float-intrinsics-strict.ll)	atan2_f32	`-mtriple=riscv64 -mattr=+zfinx -verify-machineinstrs -disable-strictnode-mutation -target-abi=lp64`

Generated 2026-10-15 08:05 UTC.