[Aarch64] llvm.aarch64.settag intrinsics cannot handle variable length

[trcrsired]

Please implement one that can handle variable lengths. Thank you

define void @stg1(ptr %p, i64 %val) {
; CHECK-LABEL: stg1:
; CHECK:       // %bb.0: // %entry
; CHECK-NEXT:    stg x0, [x0]
; CHECK-NEXT:    ret
entry:
  call void @llvm.aarch64.settag(ptr %p, i64 %val)
  ret void
}
declare void @llvm.aarch64.settag(ptr %p, i64 %a)

https://godbolt.org/z/f977nhrTW

[trcrsired]

@momchil-velikov

[llvmbot]

@llvm/issue-subscribers-backend-aarch64

Author: cqwrteur (trcrsired)

Please implement one that can handle variable lengths. Thank you

define void @<!-- -->stg1(ptr %p, i64 %val) {
; CHECK-LABEL: stg1:
; CHECK:       // %bb.0: // %entry
; CHECK-NEXT:    stg x0, [x0]
; CHECK-NEXT:    ret
entry:
  call void @<!-- -->llvm.aarch64.settag(ptr %p, i64 %val)
  ret void
}
declare void @<!-- -->llvm.aarch64.settag(ptr %p, i64 %a)

https://godbolt.org/z/f977nhrTW

[efriedma-quic]

llvm.aarch64.stg is the raw instruction.

llvm.aarch64.settag is the higher-level version which automatically generates a loop for you. Which... I guess could be adapted to support variable lengths? But I'm not sure how you'd use it.

[trcrsired]

llvm.aarch64.stg is the raw instruction.

llvm.aarch64.settag is the higher-level version which automatically generates a loop for you. Which... I guess could be adapted to support variable lengths? But I'm not sure how you'd use it.

for jit stuffs