llvm-project/llvm/test/CodeGen/Thumb/branchless-cmp.ll

110 lines
2.6 KiB
LLVM

; RUN: llc -mtriple=thumb-eabi -mcpu=cortex-m0 %s -verify-machineinstrs -o - | FileCheck %s
define i32 @test1a(i32 %a, i32 %b) {
entry:
%cmp = icmp ne i32 %a, %b
%cond = zext i1 %cmp to i32
ret i32 %cond
; CHECK-LABEL: test1a:
; CHECK-NOT: b{{(ne)|(eq)}}
; CHECK: subs r0, r0, r1
; CHECK-NEXT: subs r1, r0, #1
; CHECK-NEXT: sbcs r0, r1
}
define i32 @test1b(i32 %a, i32 %b) {
entry:
%cmp = icmp eq i32 %a, %b
%cond = zext i1 %cmp to i32
ret i32 %cond
; CHECK-LABEL: test1b:
; CHECK-NOT: b{{(ne)|(eq)}}
; CHECK: subs r1, r0, r1
; CHECK-NEXT: movs r0, #0
; CHECK-NEXT: subs r0, r0, r1
; CHECK-NEXT: adcs r0, r1
}
define i32 @test2a(i32 %a, i32 %b) {
entry:
%cmp = icmp eq i32 %a, %b
%cond = zext i1 %cmp to i32
ret i32 %cond
; CHECK-LABEL: test2a:
; CHECK-NOT: b{{(ne)|(eq)}}
; CHECK: subs r1, r0, r1
; CHECK-NEXT: movs r0, #0
; CHECK-NEXT: subs r0, r0, r1
; CHECK-NEXT: adcs r0, r1
}
define i32 @test2b(i32 %a, i32 %b) {
entry:
%cmp = icmp ne i32 %a, %b
%cond = zext i1 %cmp to i32
ret i32 %cond
; CHECK-LABEL: test2b:
; CHECK-NOT: b{{(ne)|(eq)}}
; CHECK: subs r0, r0, r1
; CHECK-NEXT: subs r1, r0, #1
; CHECK-NEXT: sbcs r0, r1
}
define i32 @test3a(i32 %a, i32 %b) {
entry:
%cmp = icmp eq i32 %a, %b
%cond = select i1 %cmp, i32 0, i32 4
ret i32 %cond
; CHECK-LABEL: test3a:
; CHECK-NOT: b{{(ne)|(eq)}}
; CHECK: subs r0, r0, r1
; CHECK-NEXT: subs r1, r0, #1
; CHECK-NEXT: sbcs r0, r1
; CHECK-NEXT: lsls r0, r0, #2
}
define i32 @test3b(i32 %a, i32 %b) {
entry:
%cmp = icmp eq i32 %a, %b
%cond = select i1 %cmp, i32 4, i32 0
ret i32 %cond
; CHECK-LABEL: test3b:
; CHECK-NOT: b{{(ne)|(eq)}}
; CHECK: subs r0, r0, r1
; CHECK-NEXT: movs r1, #0
; CHECK-NEXT: subs r1, r1, r0
; CHECK-NEXT: adcs r1, r0
; CHECK-NEXT: lsls r0, r1, #2
}
; FIXME: This one hasn't changed actually
; but could look like test3b
define i32 @test4a(i32 %a, i32 %b) {
entry:
%cmp = icmp ne i32 %a, %b
%cond = select i1 %cmp, i32 0, i32 4
ret i32 %cond
; CHECK-LABEL: test4a:
; CHECK-NOT: b{{(ne)|(eq)}}
; CHECK: mov r2, r0
; CHECK-NEXT: movs r0, #0
; CHECK-NEXT: movs r3, #4
; CHECK-NEXT: cmp r2, r1
; CHECK-NEXT: bne .[[BRANCH:[A-Z0-9_]+]]
; CHECK: mov r0, r3
; CHECK: .[[BRANCH]]:
}
define i32 @test4b(i32 %a, i32 %b) {
entry:
%cmp = icmp ne i32 %a, %b
%cond = select i1 %cmp, i32 4, i32 0
ret i32 %cond
; CHECK-LABEL: test4b:
; CHECK-NOT: b{{(ne)|(eq)}}
; CHECK: subs r0, r0, r1
; CHECK-NEXT: subs r1, r0, #1
; CHECK-NEXT: sbcs r0, r1
; CHECK-NEXT: lsls r0, r0, #2
}