6599961c17
This patch contains following enhancements to SrcRegMap and DstRegMap:
1 In findOnlyInterestingUse not only check if the Reg is two address usage,
but also check after commutation can it be two address usage.
2 If a physical register is clobbered, remove SrcRegMap entries that are
mapped to it.
3 In processTiedPairs, when create a new COPY instruction, add a SrcRegMap
entry only when the COPY instruction is coalescable. (The COPY src is
killed)
With these enhancements isProfitableToCommute can do better commute decision,
and finally more register copies are removed.
Differential Revision: https://reviews.llvm.org/D108731
30 lines
645 B
LLVM
30 lines
645 B
LLVM
; RUN: llc -mattr=mul,movw < %s -march=avr | FileCheck %s
|
|
|
|
; Tests lowering of multiplication to hardware instructions.
|
|
|
|
define i8 @mult8(i8 %a, i8 %b) {
|
|
; CHECK-LABEL: mult8:
|
|
; CHECK: muls r22, r24
|
|
; CHECK: clr r1
|
|
; CHECK: mov r24, r0
|
|
%mul = mul i8 %b, %a
|
|
ret i8 %mul
|
|
}
|
|
|
|
define i16 @mult16(i16 %a, i16 %b) {
|
|
; CHECK-LABEL: mult16:
|
|
; CHECK: muls r22, r25
|
|
; CHECK: mov r20, r0
|
|
; CHECK: mul r22, r24
|
|
; CHECK: mov r21, r0
|
|
; CHECK: mov r18, r1
|
|
; CHECK: clr r1
|
|
; CHECK: add r18, r20
|
|
; CHECK: muls r23, r24
|
|
; CHECK: clr r1
|
|
; CHECK: add r18, r0
|
|
; :TODO: finish after reworking shift instructions
|
|
%mul = mul nsw i16 %b, %a
|
|
ret i16 %mul
|
|
}
|