llvm/test/CodeGen/Thumb2/thumb2-cmn2.ll
James Molloy 5349cafffb [Thumb] Select (CMPZ X, -C) -> (CMPZ (ADDS X, C), 0)
The CMPZ #0 disappears during peepholing, leaving just a tADDi3, tADDi8 or t2ADDri. This avoids having to materialize the expensive negative constant in Thumb-1, and allows a shrinking from a 32-bit CMN to a 16-bit ADDS in Thumb-2.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@281040 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-09 12:52:24 +00:00

34 lines
724 B
LLVM

; RUN: llc -mtriple=thumb-eabi -mcpu=arm1156t2-s -mattr=+thumb2 %s -o - | FileCheck %s
; -0x000000bb = 4294967109
define i1 @f1(i32 %a) {
; CHECK-LABEL: f1:
; CHECK: adds {{r.*}}, #187
%tmp = icmp ne i32 %a, 4294967109
ret i1 %tmp
}
; -0x00aa00aa = 4283826006
define i1 @f2(i32 %a) {
; CHECK-LABEL: f2:
; CHECK: cmn.w {{r.*}}, #11141290
%tmp = icmp eq i32 %a, 4283826006
ret i1 %tmp
}
; -0xcc00cc00 = 872363008
define i1 @f3(i32 %a) {
; CHECK-LABEL: f3:
; CHECK: cmn.w {{r.*}}, #-872363008
%tmp = icmp ne i32 %a, 872363008
ret i1 %tmp
}
; -0x00110000 = 4293853184
define i1 @f4(i32 %a) {
; CHECK-LABEL: f4:
; CHECK: cmn.w {{r.*}}, #1114112
%tmp = icmp eq i32 %a, 4293853184
ret i1 %tmp
}