tests_lit/llvm2ice_tests/branch-opt.ll

; Tests the branch optimizations under O2 (against a lack of
; optimizations under Om1).

; RUN: %p2i --filetype=obj --disassemble -i %s --args -O2 \
; RUN:   | FileCheck --check-prefix=O2 %s
; RUN: %p2i --filetype=obj --disassemble -i %s --args -Om1 \
; RUN:   | FileCheck --check-prefix=OM1 %s

declare void @dummy()

; An unconditional branch to the next block should be removed.
define void @testUncondToNextBlock() {
entry:
  call void @dummy()
  br label %next
next:
  call void @dummy()
  ret void
}
; O2-LABEL: testUncondToNextBlock
; O2: call
; There will be nops for bundle align to end (for NaCl), but there should
; not be a branch.
; O2-NOT: j
; O2: call

; OM1-LABEL: testUncondToNextBlock
; OM1: call
; OM1-NEXT: jmp
; OM1: call

; For a conditional branch with a fallthrough to the next block, the
; fallthrough branch should be removed.
define void @testCondFallthroughToNextBlock(i32 %arg) {
entry:
  %cmp = icmp sge i32 %arg, 123
  br i1 %cmp, label %target, label %fallthrough
fallthrough:
  call void @dummy()
  ret void
target:
  call void @dummy()
  ret void
}
; O2-LABEL: testCondFallthroughToNextBlock
; O2: cmp {{.*}},0x7b
; O2-NEXT: jge
; O2-NOT: j
; O2: call
; O2: ret
; O2: call
; O2: ret

; OM1-LABEL: testCondFallthroughToNextBlock
; OM1: cmp {{.*}},0x7b
; OM1: jge
; OM1: cmp
; OM1: jne
; OM1: jmp
; OM1: call
; OM1: ret
; OM1: call
; OM1: ret

; For a conditional branch with the next block as the target and a
; different block as the fallthrough, the branch condition should be
; inverted, the fallthrough block changed to the target, and the
; branch to the next block removed.
define void @testCondTargetNextBlock(i32 %arg) {
entry:
  %cmp = icmp sge i32 %arg, 123
  br i1 %cmp, label %fallthrough, label %target
fallthrough:
  call void @dummy()
  ret void
target:
  call void @dummy()
  ret void
}
; O2-LABEL: testCondTargetNextBlock
; O2: cmp {{.*}},0x7b
; O2-NEXT: jl
; O2-NOT: j
; O2: call
; O2: ret
; O2: call
; O2: ret

; OM1-LABEL: testCondTargetNextBlock
; OM1: cmp {{.*}},0x7b
; OM1: jge
; OM1: cmp
; OM1: jne
; OM1: jmp
; OM1: call
; OM1: ret
; OM1: call
; OM1: ret