llvm-for-llvmta/test/Transforms/LoopDeletion/zero-btc.ll

381 lines
10 KiB
LLVM

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -loop-deletion -S | FileCheck %s
@G = external global i32
define void @test_trivial() {
; CHECK-LABEL: @test_trivial(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: store i32 0, i32* @G, align 4
; CHECK-NEXT: br i1 false, label [[LOOP_LOOP_CRIT_EDGE:%.*]], label [[EXIT:%.*]]
; CHECK: loop.loop_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: exit:
; CHECK-NEXT: ret void
;
entry:
br label %loop
loop:
store i32 0, i32* @G
br i1 false, label %loop, label %exit
exit:
ret void
}
define void @test_bottom_tested() {
; CHECK-LABEL: @test_bottom_tested(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ]
; CHECK-NEXT: store i32 0, i32* @G, align 4
; CHECK-NEXT: [[IV_INC:%.*]] = add i32 [[IV]], 1
; CHECK-NEXT: [[BE_TAKEN:%.*]] = icmp ne i32 [[IV_INC]], 1
; CHECK-NEXT: br i1 [[BE_TAKEN]], label [[LOOP_LOOP_CRIT_EDGE:%.*]], label [[EXIT:%.*]]
; CHECK: loop.loop_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: exit:
; CHECK-NEXT: ret void
;
entry:
br label %loop
loop:
%iv = phi i32 [ 0, %entry], [ %iv.inc, %loop ]
store i32 0, i32* @G
%iv.inc = add i32 %iv, 1
%be_taken = icmp ne i32 %iv.inc, 1
br i1 %be_taken, label %loop, label %exit
exit:
ret void
}
define void @test_early_exit() {
; CHECK-LABEL: @test_early_exit(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ]
; CHECK-NEXT: store i32 0, i32* @G, align 4
; CHECK-NEXT: [[IV_INC:%.*]] = add i32 [[IV]], 1
; CHECK-NEXT: [[BE_TAKEN:%.*]] = icmp ne i32 [[IV_INC]], 1
; CHECK-NEXT: br i1 [[BE_TAKEN]], label [[LATCH:%.*]], label [[EXIT:%.*]]
; CHECK: latch:
; CHECK-NEXT: br label [[LATCH_SPLIT:%.*]]
; CHECK: latch.split:
; CHECK-NEXT: unreachable
; CHECK: exit:
; CHECK-NEXT: ret void
;
entry:
br label %loop
loop:
%iv = phi i32 [ 0, %entry], [ %iv.inc, %latch ]
store i32 0, i32* @G
%iv.inc = add i32 %iv, 1
%be_taken = icmp ne i32 %iv.inc, 1
br i1 %be_taken, label %latch, label %exit
latch:
br label %loop
exit:
ret void
}
define void @test_multi_exit1() {
; CHECK-LABEL: @test_multi_exit1(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ]
; CHECK-NEXT: store i32 0, i32* @G, align 4
; CHECK-NEXT: [[IV_INC:%.*]] = add i32 [[IV]], 1
; CHECK-NEXT: [[BE_TAKEN:%.*]] = icmp ne i32 [[IV_INC]], 1
; CHECK-NEXT: br i1 [[BE_TAKEN]], label [[LATCH:%.*]], label [[EXIT:%.*]]
; CHECK: latch:
; CHECK-NEXT: store i32 1, i32* @G, align 4
; CHECK-NEXT: [[COND2:%.*]] = icmp ult i32 [[IV_INC]], 30
; CHECK-NEXT: br i1 [[COND2]], label [[LATCH_LOOP_CRIT_EDGE:%.*]], label [[EXIT]]
; CHECK: latch.loop_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: exit:
; CHECK-NEXT: ret void
;
entry:
br label %loop
loop:
%iv = phi i32 [ 0, %entry], [ %iv.inc, %latch ]
store i32 0, i32* @G
%iv.inc = add i32 %iv, 1
%be_taken = icmp ne i32 %iv.inc, 1
br i1 %be_taken, label %latch, label %exit
latch:
store i32 1, i32* @G
%cond2 = icmp ult i32 %iv.inc, 30
br i1 %cond2, label %loop, label %exit
exit:
ret void
}
define void @test_multi_exit2() {
; CHECK-LABEL: @test_multi_exit2(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: store i32 0, i32* @G, align 4
; CHECK-NEXT: br i1 true, label [[LATCH:%.*]], label [[EXIT:%.*]]
; CHECK: latch:
; CHECK-NEXT: store i32 1, i32* @G, align 4
; CHECK-NEXT: br i1 false, label [[LATCH_LOOP_CRIT_EDGE:%.*]], label [[EXIT]]
; CHECK: latch.loop_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: exit:
; CHECK-NEXT: ret void
;
entry:
br label %loop
loop:
store i32 0, i32* @G
br i1 true, label %latch, label %exit
latch:
store i32 1, i32* @G
br i1 false, label %loop, label %exit
exit:
ret void
}
; TODO: SCEV seems not to recognize this as a zero btc loop
define void @test_multi_exit3(i1 %cond1) {
; CHECK-LABEL: @test_multi_exit3(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_INC:%.*]], [[LATCH:%.*]] ]
; CHECK-NEXT: store i32 0, i32* @G, align 4
; CHECK-NEXT: br i1 [[COND1:%.*]], label [[LATCH]], label [[EXIT:%.*]]
; CHECK: latch:
; CHECK-NEXT: store i32 1, i32* @G, align 4
; CHECK-NEXT: [[IV_INC]] = add i32 [[IV]], 1
; CHECK-NEXT: [[BE_TAKEN:%.*]] = icmp ne i32 [[IV_INC]], 1
; CHECK-NEXT: br i1 [[BE_TAKEN]], label [[LOOP]], label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret void
;
entry:
br label %loop
loop:
%iv = phi i32 [ 0, %entry], [ %iv.inc, %latch ]
store i32 0, i32* @G
br i1 %cond1, label %latch, label %exit
latch:
store i32 1, i32* @G
%iv.inc = add i32 %iv, 1
%be_taken = icmp ne i32 %iv.inc, 1
br i1 %be_taken, label %loop, label %exit
exit:
ret void
}
; Subtle - This is either zero btc, or infinite, thus, can't break
; backedge
define void @test_multi_exit4(i1 %cond1, i1 %cond2) {
; CHECK-LABEL: @test_multi_exit4(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: store i32 0, i32* @G, align 4
; CHECK-NEXT: br i1 [[COND1:%.*]], label [[LATCH:%.*]], label [[EXIT:%.*]]
; CHECK: latch:
; CHECK-NEXT: store i32 1, i32* @G, align 4
; CHECK-NEXT: br i1 [[COND2:%.*]], label [[LOOP]], label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret void
;
entry:
br label %loop
loop:
store i32 0, i32* @G
br i1 %cond1, label %latch, label %exit
latch:
store i32 1, i32* @G
br i1 %cond2, label %loop, label %exit
exit:
ret void
}
; A simple case with multiple exit blocks
define void @test_multi_exit5() {
; CHECK-LABEL: @test_multi_exit5(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: store i32 0, i32* @G, align 4
; CHECK-NEXT: br i1 true, label [[LATCH:%.*]], label [[EXIT1:%.*]]
; CHECK: latch:
; CHECK-NEXT: store i32 1, i32* @G, align 4
; CHECK-NEXT: br i1 false, label [[LATCH_LOOP_CRIT_EDGE:%.*]], label [[EXIT2:%.*]]
; CHECK: latch.loop_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: exit1:
; CHECK-NEXT: ret void
; CHECK: exit2:
; CHECK-NEXT: ret void
;
entry:
br label %loop
loop:
store i32 0, i32* @G
br i1 true, label %latch, label %exit1
latch:
store i32 1, i32* @G
br i1 false, label %loop, label %exit2
exit1:
ret void
exit2:
ret void
}
define void @test_live_inner() {
; CHECK-LABEL: @test_live_inner(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: store i32 0, i32* @G, align 4
; CHECK-NEXT: br label [[INNER:%.*]]
; CHECK: inner:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[LOOP]] ], [ [[IV_INC:%.*]], [[INNER]] ]
; CHECK-NEXT: store i32 [[IV]], i32* @G, align 4
; CHECK-NEXT: [[IV_INC]] = add i32 [[IV]], 1
; CHECK-NEXT: [[CND:%.*]] = icmp ult i32 [[IV_INC]], 200
; CHECK-NEXT: br i1 [[CND]], label [[INNER]], label [[LATCH:%.*]]
; CHECK: latch:
; CHECK-NEXT: br i1 false, label [[LATCH_LOOP_CRIT_EDGE:%.*]], label [[EXIT:%.*]]
; CHECK: latch.loop_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: exit:
; CHECK-NEXT: ret void
;
entry:
br label %loop
loop:
store i32 0, i32* @G
br label %inner
inner:
%iv = phi i32 [0, %loop], [%iv.inc, %inner]
store i32 %iv, i32* @G
%iv.inc = add i32 %iv, 1
%cnd = icmp ult i32 %iv.inc, 200
br i1 %cnd, label %inner, label %latch
latch:
br i1 false, label %loop, label %exit
exit:
ret void
}
define void @test_live_outer() {
; CHECK-LABEL: @test_live_outer(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_INC:%.*]], [[LATCH:%.*]] ]
; CHECK-NEXT: br label [[INNER:%.*]]
; CHECK: inner:
; CHECK-NEXT: store i32 0, i32* @G, align 4
; CHECK-NEXT: br i1 false, label [[INNER_INNER_CRIT_EDGE:%.*]], label [[LATCH]]
; CHECK: inner.inner_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: latch:
; CHECK-NEXT: store i32 [[IV]], i32* @G, align 4
; CHECK-NEXT: [[IV_INC]] = add i32 [[IV]], 1
; CHECK-NEXT: [[CND:%.*]] = icmp ult i32 [[IV_INC]], 200
; CHECK-NEXT: br i1 [[CND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: ret void
;
entry:
br label %loop
loop:
%iv = phi i32 [0, %entry], [%iv.inc, %latch]
br label %inner
inner:
store i32 0, i32* @G
br i1 false, label %inner, label %latch
latch:
store i32 %iv, i32* @G
%iv.inc = add i32 %iv, 1
%cnd = icmp ult i32 %iv.inc, 200
br i1 %cnd, label %loop, label %exit
exit:
ret void
}
; Key point is that inner_latch drops out of the outer loop when
; the inner loop is deleted, and thus the lcssa phi needs to be
; in the inner_latch block to preserve LCSSA. We either have to
; insert the LCSSA phi, or not break the inner backedge.
define void @loop_nest_lcssa() {
; CHECK-LABEL: @loop_nest_lcssa(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = add i32 1, 2
; CHECK-NEXT: br label [[OUTER_HEADER:%.*]]
; CHECK: outer_header:
; CHECK-NEXT: br label [[INNER_HEADER:%.*]]
; CHECK: inner_header:
; CHECK-NEXT: br i1 false, label [[INNER_LATCH:%.*]], label [[OUTER_LATCH:%.*]]
; CHECK: inner_latch:
; CHECK-NEXT: [[DOTLCSSA:%.*]] = phi i32 [ [[TMP0]], [[INNER_HEADER]] ]
; CHECK-NEXT: br i1 false, label [[INNER_LATCH_INNER_HEADER_CRIT_EDGE:%.*]], label [[LOOPEXIT:%.*]]
; CHECK: inner_latch.inner_header_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: outer_latch:
; CHECK-NEXT: br label [[OUTER_HEADER]]
; CHECK: loopexit:
; CHECK-NEXT: [[DOTLCSSA32:%.*]] = phi i32 [ [[DOTLCSSA]], [[INNER_LATCH]] ]
; CHECK-NEXT: unreachable
;
entry:
br label %outer_header
outer_header:
%0 = add i32 1, 2
br label %inner_header
inner_header:
br i1 false, label %inner_latch, label %outer_latch
inner_latch:
br i1 false, label %inner_header, label %loopexit
outer_latch:
br label %outer_header
loopexit:
%.lcssa32 = phi i32 [ %0, %inner_latch ]
unreachable
}