llvm/test/CodeGen/Thumb2/thumb2-cmp.ll
Jakob Stoklund Olesen 28e104bcb0 Explicitly request physreg coalesing for a bunch of Thumb2 unit tests.
These tests all follow the same pattern:

	mov	r2, r0
	movs	r0, #0
	$CMP	r2, r1
	it	eq
	moveq	r0, #1
	bx	lr

The first 'mov' can be eliminated by rematerializing 'movs r0, #0' below the
test instruction:

	$CMP	r0, r1
	mov.w	r0, #0
	it	eq
	moveq	r0, #1
	bx	lr

So far, only physreg coalescing can do that. The register allocators won't yet
split live ranges just to eliminate copies. They can learn, but this particular
problem is not likely to show up in real code. It only appears because r0 is
used for both the function argument and return value.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130858 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-04 19:02:07 +00:00

59 lines
1.2 KiB
LLVM

; RUN: llc < %s -march=thumb -mattr=+thumb2 -join-physregs | FileCheck %s
; These tests implicitly depend on 'movs r0, #0' being rematerialized below the
; test as 'mov.w r0, #0'. So far, that requires physreg joining.
; 0x000000bb = 187
define i1 @f1(i32 %a) {
; CHECK: f1:
; CHECK: cmp r0, #187
%tmp = icmp ne i32 %a, 187
ret i1 %tmp
}
; 0x00aa00aa = 11141290
define i1 @f2(i32 %a) {
; CHECK: f2:
; CHECK: cmp.w r0, #11141290
%tmp = icmp eq i32 %a, 11141290
ret i1 %tmp
}
; 0xcc00cc00 = 3422604288
define i1 @f3(i32 %a) {
; CHECK: f3:
; CHECK: cmp.w r0, #-872363008
%tmp = icmp ne i32 %a, 3422604288
ret i1 %tmp
}
; 0xdddddddd = 3722304989
define i1 @f4(i32 %a) {
; CHECK: f4:
; CHECK: cmp.w r0, #-572662307
%tmp = icmp ne i32 %a, 3722304989
ret i1 %tmp
}
; 0x00110000 = 1114112
define i1 @f5(i32 %a) {
; CHECK: f5:
; CHECK: cmp.w r0, #1114112
%tmp = icmp eq i32 %a, 1114112
ret i1 %tmp
}
; Check that we don't do an invalid (a > b) --> !(a < b + 1) transform.
;
; CHECK: f6:
; CHECK-NOT: cmp.w r0, #-2147483648
; CHECK: bx lr
define i32 @f6(i32 %a) {
%tmp = icmp sgt i32 %a, 2147483647
br i1 %tmp, label %true, label %false
true:
ret i32 2
false:
ret i32 0
}