llvm-6502/test/CodeGen/Thumb/iabs.ll
Anton Korobeynikov 244455e6d6 Peephole optimization for ABS on ARM.
Patch by Ana Pazos!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141365 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-07 16:15:08 +00:00

23 lines
530 B
LLVM

; RUN: llc < %s -march=thumb -stats |& \
; RUN: grep {4 .*Number of machine instrs printed}
;; Integer absolute value, should produce something as good as:
;; Thumb:
;; movs r0, r0
;; bpl
;; rsb r0, r0, #0 (with opitmization, bpl + rsb is if-converted into rsbmi)
;; bx lr
define i32 @test(i32 %a) {
%tmp1neg = sub i32 0, %a
%b = icmp sgt i32 %a, -1
%abs = select i1 %b, i32 %a, i32 %tmp1neg
ret i32 %abs
; CHECK: movs r0, r0
; CHECK: bpl
; CHECK: rsb r0, r0, #0
; CHECK: bx lr
}