caio/clang-p2996
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
Files
6829db727e9e67dfdb70dd0846ffd4e48e00a98d
clang-p2996/llvm/test/Transforms/LoopDeletion/eval_first_iteration.ll
Max Kazantsev 7c73c2ede8 [LoopDeletion] Benefit from branches by undef conditions when symbolically executing 1st iteration 
We can exploit branches by `undef` condition. Frankly, the LangRef says that
such branches are UB, so we can assume that all outgoing edges of such blocks
are dead.

However, from practical perspective, we know that this is not supported correctly
in some other places. So we are being conservative about it.

Branch by undef is treated in the following way:
- If it is a loop-exiting branch, we always assume it exits the loop;
- If not, we arbitrarily assume it takes `true` value.

Differential Revision: https://reviews.llvm.org/D104689
Reviewed By: nikic
2021-06-28 11:39:46 +07:00

1049 lines
39 KiB
LLVM
Raw Blame History

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -loop-deletion -S | FileCheck %s
; RUN: opt < %s -passes='loop(loop-deletion)' -S | FileCheck %s
; The idea is that we know that %is.positive is true on the 1st iteration,
; it means that we can evaluate %merge.phi = %sub on the 1st iteration,
; and therefore prove that %sum.next = %sum + %sub = %sum + %limit - %sum = %limit,
; and predicate is false.
; TODO: We can break the backedge here.
define i32 @test_ne(i32 %limit) {
; CHECK-LABEL: @test_ne(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[LOOP_GUARD:%.*]] = icmp sgt i32 [[LIMIT:%.*]], 0
; CHECK-NEXT: br i1 [[LOOP_GUARD]], label [[LOOP_PREHEADER:%.*]], label [[FAILURE:%.*]]
; CHECK: loop.preheader:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ [[SUM_NEXT:%.*]], [[BACKEDGE:%.*]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 [[LIMIT]], [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: br i1 [[IS_POSITIVE]], label [[BACKEDGE]], label [[IF_FALSE:%.*]]
; CHECK: if.false:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE]] ], [ [[SUB]], [[LOOP]] ]
; CHECK-NEXT: [[SUM_NEXT]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp ne i32 [[SUM_NEXT]], [[LIMIT]]
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[DONE:%.*]]
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
%loop_guard = icmp sgt i32 %limit, 0
br i1 %loop_guard, label %loop, label %failure
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 %limit, %sum
%is.positive = icmp sgt i32 %sub, 0
br i1 %is.positive, label %backedge, label %if.false
if.false: ; preds = %loop
br label %backedge
backedge: ; preds = %if.false, %loop
%merge.phi = phi i32 [ 0, %if.false ], [ %sub, %loop ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp ne i32 %sum.next, %limit
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
; TODO: We can break the backedge here.
define i32 @test_slt(i32 %limit) {
; CHECK-LABEL: @test_slt(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[LOOP_GUARD:%.*]] = icmp sgt i32 [[LIMIT:%.*]], 0
; CHECK-NEXT: br i1 [[LOOP_GUARD]], label [[LOOP_PREHEADER:%.*]], label [[FAILURE:%.*]]
; CHECK: loop.preheader:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ [[SUM_NEXT:%.*]], [[BACKEDGE:%.*]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 [[LIMIT]], [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: br i1 [[IS_POSITIVE]], label [[BACKEDGE]], label [[IF_FALSE:%.*]]
; CHECK: if.false:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE]] ], [ [[SUB]], [[LOOP]] ]
; CHECK-NEXT: [[SUM_NEXT]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp slt i32 [[SUM_NEXT]], [[LIMIT]]
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[DONE:%.*]]
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
%loop_guard = icmp sgt i32 %limit, 0
br i1 %loop_guard, label %loop, label %failure
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 %limit, %sum
%is.positive = icmp sgt i32 %sub, 0
br i1 %is.positive, label %backedge, label %if.false
if.false: ; preds = %loop
br label %backedge
backedge: ; preds = %if.false, %loop
%merge.phi = phi i32 [ 0, %if.false ], [ %sub, %loop ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp slt i32 %sum.next, %limit
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
; TODO: We can break the backedge here.
define i32 @test_ult(i32 %limit) {
; CHECK-LABEL: @test_ult(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[LOOP_GUARD:%.*]] = icmp sgt i32 [[LIMIT:%.*]], 0
; CHECK-NEXT: br i1 [[LOOP_GUARD]], label [[LOOP_PREHEADER:%.*]], label [[FAILURE:%.*]]
; CHECK: loop.preheader:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ [[SUM_NEXT:%.*]], [[BACKEDGE:%.*]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 [[LIMIT]], [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: br i1 [[IS_POSITIVE]], label [[BACKEDGE]], label [[IF_FALSE:%.*]]
; CHECK: if.false:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE]] ], [ [[SUB]], [[LOOP]] ]
; CHECK-NEXT: [[SUM_NEXT]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp ult i32 [[SUM_NEXT]], [[LIMIT]]
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[DONE:%.*]]
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
%loop_guard = icmp sgt i32 %limit, 0
br i1 %loop_guard, label %loop, label %failure
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 %limit, %sum
%is.positive = icmp sgt i32 %sub, 0
br i1 %is.positive, label %backedge, label %if.false
if.false: ; preds = %loop
br label %backedge
backedge: ; preds = %if.false, %loop
%merge.phi = phi i32 [ 0, %if.false ], [ %sub, %loop ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp ult i32 %sum.next, %limit
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
; TODO: We can break the backedge here.
define i32 @test_sgt(i32 %limit) {
; CHECK-LABEL: @test_sgt(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[LOOP_GUARD:%.*]] = icmp sgt i32 [[LIMIT:%.*]], 0
; CHECK-NEXT: br i1 [[LOOP_GUARD]], label [[LOOP_PREHEADER:%.*]], label [[FAILURE:%.*]]
; CHECK: loop.preheader:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ [[SUM_NEXT:%.*]], [[BACKEDGE:%.*]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 [[LIMIT]], [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: br i1 [[IS_POSITIVE]], label [[BACKEDGE]], label [[IF_FALSE:%.*]]
; CHECK: if.false:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE]] ], [ [[SUB]], [[LOOP]] ]
; CHECK-NEXT: [[SUM_NEXT]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp sgt i32 [[SUM_NEXT]], [[LIMIT]]
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[DONE:%.*]]
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
%loop_guard = icmp sgt i32 %limit, 0
br i1 %loop_guard, label %loop, label %failure
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 %limit, %sum
%is.positive = icmp sgt i32 %sub, 0
br i1 %is.positive, label %backedge, label %if.false
if.false: ; preds = %loop
br label %backedge
backedge: ; preds = %if.false, %loop
%merge.phi = phi i32 [ 0, %if.false ], [ %sub, %loop ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp sgt i32 %sum.next, %limit
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
; TODO: We can break the backedge here.
define i32 @test_ugt(i32 %limit) {
; CHECK-LABEL: @test_ugt(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[LOOP_GUARD:%.*]] = icmp sgt i32 [[LIMIT:%.*]], 0
; CHECK-NEXT: br i1 [[LOOP_GUARD]], label [[LOOP_PREHEADER:%.*]], label [[FAILURE:%.*]]
; CHECK: loop.preheader:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ [[SUM_NEXT:%.*]], [[BACKEDGE:%.*]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 [[LIMIT]], [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: br i1 [[IS_POSITIVE]], label [[BACKEDGE]], label [[IF_FALSE:%.*]]
; CHECK: if.false:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE]] ], [ [[SUB]], [[LOOP]] ]
; CHECK-NEXT: [[SUM_NEXT]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp ugt i32 [[SUM_NEXT]], [[LIMIT]]
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[DONE:%.*]]
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
%loop_guard = icmp sgt i32 %limit, 0
br i1 %loop_guard, label %loop, label %failure
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 %limit, %sum
%is.positive = icmp sgt i32 %sub, 0
br i1 %is.positive, label %backedge, label %if.false
if.false: ; preds = %loop
br label %backedge
backedge: ; preds = %if.false, %loop
%merge.phi = phi i32 [ 0, %if.false ], [ %sub, %loop ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp ugt i32 %sum.next, %limit
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
; TODO: We can break the backedge here.
define i32 @test_multiple_pred(i32 %limit) {
; CHECK-LABEL: @test_multiple_pred(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[LOOP_GUARD:%.*]] = icmp sgt i32 [[LIMIT:%.*]], 0
; CHECK-NEXT: br i1 [[LOOP_GUARD]], label [[LOOP_PREHEADER:%.*]], label [[FAILURE:%.*]]
; CHECK: loop.preheader:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ [[SUM_NEXT:%.*]], [[BACKEDGE:%.*]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 [[LIMIT]], [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: br i1 [[IS_POSITIVE]], label [[IF_TRUE:%.*]], label [[IF_FALSE:%.*]]
; CHECK: if.true:
; CHECK-NEXT: switch i32 [[LIMIT]], label [[FAILURE_LOOPEXIT:%.*]] [
; CHECK-NEXT: i32 100, label [[BACKEDGE]]
; CHECK-NEXT: i32 200, label [[BACKEDGE]]
; CHECK-NEXT: ]
; CHECK: if.false:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE]] ], [ [[SUB]], [[IF_TRUE]] ], [ [[SUB]], [[IF_TRUE]] ]
; CHECK-NEXT: [[SUM_NEXT]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp ne i32 [[SUM_NEXT]], [[LIMIT]]
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[DONE:%.*]]
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure.loopexit:
; CHECK-NEXT: br label [[FAILURE]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
%loop_guard = icmp sgt i32 %limit, 0
br i1 %loop_guard, label %loop, label %failure
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 %limit, %sum
%is.positive = icmp sgt i32 %sub, 0
br i1 %is.positive, label %if.true, label %if.false
if.true:
switch i32 %limit, label %failure [
i32 100, label %backedge
i32 200, label %backedge
]
if.false: ; preds = %loop
br label %backedge
backedge:
%merge.phi = phi i32 [ 0, %if.false ], [ %sub, %if.true ], [ %sub, %if.true ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp ne i32 %sum.next, %limit
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
define i32 @test_ne_const() {
; CHECK-LABEL: @test_ne_const(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 4, [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: br i1 [[IS_POSITIVE]], label [[BACKEDGE:%.*]], label [[IF_FALSE:%.*]]
; CHECK: if.false:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE]] ], [ [[SUB]], [[LOOP]] ]
; CHECK-NEXT: [[SUM_NEXT:%.*]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp ne i32 [[SUM_NEXT]], 4
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[BACKEDGE_LOOP_CRIT_EDGE:%.*]], label [[DONE:%.*]]
; CHECK: backedge.loop_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
br label %loop
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 4, %sum
%is.positive = icmp sgt i32 %sub, 0
br i1 %is.positive, label %backedge, label %if.false
if.false: ; preds = %loop
br label %backedge
backedge: ; preds = %if.false, %loop
%merge.phi = phi i32 [ 0, %if.false ], [ %sub, %loop ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp ne i32 %sum.next, 4
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
define i32 @test_slt_const() {
; CHECK-LABEL: @test_slt_const(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 4, [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: br i1 [[IS_POSITIVE]], label [[BACKEDGE:%.*]], label [[IF_FALSE:%.*]]
; CHECK: if.false:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE]] ], [ [[SUB]], [[LOOP]] ]
; CHECK-NEXT: [[SUM_NEXT:%.*]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp slt i32 [[SUM_NEXT]], 4
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[BACKEDGE_LOOP_CRIT_EDGE:%.*]], label [[DONE:%.*]]
; CHECK: backedge.loop_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
br label %loop
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 4, %sum
%is.positive = icmp sgt i32 %sub, 0
br i1 %is.positive, label %backedge, label %if.false
if.false: ; preds = %loop
br label %backedge
backedge: ; preds = %if.false, %loop
%merge.phi = phi i32 [ 0, %if.false ], [ %sub, %loop ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp slt i32 %sum.next, 4
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
define i32 @test_ult_const() {
; CHECK-LABEL: @test_ult_const(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 4, [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: br i1 [[IS_POSITIVE]], label [[BACKEDGE:%.*]], label [[IF_FALSE:%.*]]
; CHECK: if.false:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE]] ], [ [[SUB]], [[LOOP]] ]
; CHECK-NEXT: [[SUM_NEXT:%.*]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp ult i32 [[SUM_NEXT]], 4
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[BACKEDGE_LOOP_CRIT_EDGE:%.*]], label [[DONE:%.*]]
; CHECK: backedge.loop_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
br label %loop
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 4, %sum
%is.positive = icmp sgt i32 %sub, 0
br i1 %is.positive, label %backedge, label %if.false
if.false: ; preds = %loop
br label %backedge
backedge: ; preds = %if.false, %loop
%merge.phi = phi i32 [ 0, %if.false ], [ %sub, %loop ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp ult i32 %sum.next, 4
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
define i32 @test_sgt_const() {
; CHECK-LABEL: @test_sgt_const(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 4, [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: br i1 [[IS_POSITIVE]], label [[BACKEDGE:%.*]], label [[IF_FALSE:%.*]]
; CHECK: if.false:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE]] ], [ [[SUB]], [[LOOP]] ]
; CHECK-NEXT: [[SUM_NEXT:%.*]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp sgt i32 [[SUM_NEXT]], 4
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[BACKEDGE_LOOP_CRIT_EDGE:%.*]], label [[DONE:%.*]]
; CHECK: backedge.loop_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
br label %loop
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 4, %sum
%is.positive = icmp sgt i32 %sub, 0
br i1 %is.positive, label %backedge, label %if.false
if.false: ; preds = %loop
br label %backedge
backedge: ; preds = %if.false, %loop
%merge.phi = phi i32 [ 0, %if.false ], [ %sub, %loop ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp sgt i32 %sum.next, 4
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
define i32 @test_ugt_const() {
; CHECK-LABEL: @test_ugt_const(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 4, [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: br i1 [[IS_POSITIVE]], label [[BACKEDGE:%.*]], label [[IF_FALSE:%.*]]
; CHECK: if.false:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE]] ], [ [[SUB]], [[LOOP]] ]
; CHECK-NEXT: [[SUM_NEXT:%.*]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp ugt i32 [[SUM_NEXT]], 4
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[BACKEDGE_LOOP_CRIT_EDGE:%.*]], label [[DONE:%.*]]
; CHECK: backedge.loop_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
br label %loop
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 4, %sum
%is.positive = icmp sgt i32 %sub, 0
br i1 %is.positive, label %backedge, label %if.false
if.false: ; preds = %loop
br label %backedge
backedge: ; preds = %if.false, %loop
%merge.phi = phi i32 [ 0, %if.false ], [ %sub, %loop ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp ugt i32 %sum.next, 4
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
define i32 @test_multiple_pred_const() {
; CHECK-LABEL: @test_multiple_pred_const(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 4, [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: br i1 [[IS_POSITIVE]], label [[IF_TRUE:%.*]], label [[IF_FALSE:%.*]]
; CHECK: if.true:
; CHECK-NEXT: switch i32 4, label [[FAILURE:%.*]] [
; CHECK-NEXT: i32 100, label [[BACKEDGE:%.*]]
; CHECK-NEXT: i32 200, label [[BACKEDGE]]
; CHECK-NEXT: ]
; CHECK: if.false:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE]] ], [ [[SUB]], [[IF_TRUE]] ], [ [[SUB]], [[IF_TRUE]] ]
; CHECK-NEXT: [[SUM_NEXT:%.*]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp ne i32 [[SUM_NEXT]], 4
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[BACKEDGE_LOOP_CRIT_EDGE:%.*]], label [[DONE:%.*]]
; CHECK: backedge.loop_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
br label %loop
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 4, %sum
%is.positive = icmp sgt i32 %sub, 0
br i1 %is.positive, label %if.true, label %if.false
if.true:
switch i32 4, label %failure [
i32 100, label %backedge
i32 200, label %backedge
]
if.false: ; preds = %loop
br label %backedge
backedge:
%merge.phi = phi i32 [ 0, %if.false ], [ %sub, %if.true ], [ %sub, %if.true ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp ne i32 %sum.next, 4
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
define i32 @test_multiple_pred_2(i1 %cond, i1 %cond2) {
; CHECK-LABEL: @test_multiple_pred_2(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 4, [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: br i1 [[IS_POSITIVE]], label [[IF_TRUE:%.*]], label [[IF_FALSE:%.*]]
; CHECK: if.true:
; CHECK-NEXT: br i1 [[COND:%.*]], label [[IF_TRUE_1:%.*]], label [[IF_TRUE_2:%.*]]
; CHECK: if.true.1:
; CHECK-NEXT: br label [[BACKEDGE:%.*]]
; CHECK: if.true.2:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: if.false:
; CHECK-NEXT: br i1 [[COND2:%.*]], label [[IF_FALSE_1:%.*]], label [[IF_FALSE_2:%.*]]
; CHECK: if.false.1:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: if.false.2:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE_1]] ], [ 0, [[IF_FALSE_2]] ], [ [[SUB]], [[IF_TRUE_1]] ], [ [[SUB]], [[IF_TRUE_2]] ]
; CHECK-NEXT: [[SUM_NEXT:%.*]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp ne i32 [[SUM_NEXT]], 4
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[BACKEDGE_LOOP_CRIT_EDGE:%.*]], label [[DONE:%.*]]
; CHECK: backedge.loop_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
br label %loop
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 4, %sum
%is.positive = icmp sgt i32 %sub, 0
br i1 %is.positive, label %if.true, label %if.false
if.true:
br i1 %cond, label %if.true.1, label %if.true.2
if.true.1:
br label %backedge
if.true.2:
br label %backedge
if.false: ; preds = %loop
br i1 %cond2, label %if.false.1, label %if.false.2
if.false.1:
br label %backedge
if.false.2:
br label %backedge
backedge:
%merge.phi = phi i32 [ 0, %if.false.1 ], [ 0, %if.false.2 ], [ %sub, %if.true.1 ], [ %sub, %if.true.2 ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp ne i32 %sum.next, 4
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
define i32 @test_multiple_pred_undef_1(i1 %cond, i1 %cond2) {
; CHECK-LABEL: @test_multiple_pred_undef_1(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 4, [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: br i1 [[IS_POSITIVE]], label [[IF_TRUE:%.*]], label [[IF_FALSE:%.*]]
; CHECK: if.true:
; CHECK-NEXT: br i1 [[COND:%.*]], label [[IF_TRUE_1:%.*]], label [[IF_TRUE_2:%.*]]
; CHECK: if.true.1:
; CHECK-NEXT: br label [[BACKEDGE:%.*]]
; CHECK: if.true.2:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: if.false:
; CHECK-NEXT: br i1 [[COND2:%.*]], label [[IF_FALSE_1:%.*]], label [[IF_FALSE_2:%.*]]
; CHECK: if.false.1:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: if.false.2:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE_1]] ], [ 0, [[IF_FALSE_2]] ], [ [[SUB]], [[IF_TRUE_1]] ], [ undef, [[IF_TRUE_2]] ]
; CHECK-NEXT: [[SUM_NEXT:%.*]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp ne i32 [[SUM_NEXT]], 4
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[BACKEDGE_LOOP_CRIT_EDGE:%.*]], label [[DONE:%.*]]
; CHECK: backedge.loop_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
br label %loop
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 4, %sum
%is.positive = icmp sgt i32 %sub, 0
br i1 %is.positive, label %if.true, label %if.false
if.true:
br i1 %cond, label %if.true.1, label %if.true.2
if.true.1:
br label %backedge
if.true.2:
br label %backedge
if.false: ; preds = %loop
br i1 %cond2, label %if.false.1, label %if.false.2
if.false.1:
br label %backedge
if.false.2:
br label %backedge
backedge:
%merge.phi = phi i32 [ 0, %if.false.1 ], [ 0, %if.false.2 ], [ %sub, %if.true.1 ], [ undef, %if.true.2 ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp ne i32 %sum.next, 4
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
define i32 @test_multiple_pred_undef_2(i1 %cond, i1 %cond2) {
; CHECK-LABEL: @test_multiple_pred_undef_2(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 4, [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: br i1 [[IS_POSITIVE]], label [[IF_TRUE:%.*]], label [[IF_FALSE:%.*]]
; CHECK: if.true:
; CHECK-NEXT: br i1 [[COND:%.*]], label [[IF_TRUE_1:%.*]], label [[IF_TRUE_2:%.*]]
; CHECK: if.true.1:
; CHECK-NEXT: br label [[BACKEDGE:%.*]]
; CHECK: if.true.2:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: if.false:
; CHECK-NEXT: br i1 [[COND2:%.*]], label [[IF_FALSE_1:%.*]], label [[IF_FALSE_2:%.*]]
; CHECK: if.false.1:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: if.false.2:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE_1]] ], [ 0, [[IF_FALSE_2]] ], [ undef, [[IF_TRUE_1]] ], [ [[SUB]], [[IF_TRUE_2]] ]
; CHECK-NEXT: [[SUM_NEXT:%.*]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp ne i32 [[SUM_NEXT]], 4
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[BACKEDGE_LOOP_CRIT_EDGE:%.*]], label [[DONE:%.*]]
; CHECK: backedge.loop_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
br label %loop
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 4, %sum
%is.positive = icmp sgt i32 %sub, 0
br i1 %is.positive, label %if.true, label %if.false
if.true:
br i1 %cond, label %if.true.1, label %if.true.2
if.true.1:
br label %backedge
if.true.2:
br label %backedge
if.false: ; preds = %loop
br i1 %cond2, label %if.false.1, label %if.false.2
if.false.1:
br label %backedge
if.false.2:
br label %backedge
backedge:
%merge.phi = phi i32 [ 0, %if.false.1 ], [ 0, %if.false.2 ], [ undef, %if.true.1 ], [ %sub, %if.true.2 ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp ne i32 %sum.next, 4
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
define i32 @test_multiple_pred_undef_3(i1 %cond, i1 %cond2) {
; CHECK-LABEL: @test_multiple_pred_undef_3(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 4, [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: br i1 [[IS_POSITIVE]], label [[IF_TRUE:%.*]], label [[IF_FALSE:%.*]]
; CHECK: if.true:
; CHECK-NEXT: br i1 [[COND:%.*]], label [[IF_TRUE_1:%.*]], label [[IF_TRUE_2:%.*]]
; CHECK: if.true.1:
; CHECK-NEXT: br label [[BACKEDGE:%.*]]
; CHECK: if.true.2:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: if.false:
; CHECK-NEXT: br i1 [[COND2:%.*]], label [[IF_FALSE_1:%.*]], label [[IF_FALSE_2:%.*]]
; CHECK: if.false.1:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: if.false.2:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE_1]] ], [ 0, [[IF_FALSE_2]] ], [ undef, [[IF_TRUE_1]] ], [ undef, [[IF_TRUE_2]] ]
; CHECK-NEXT: [[SUM_NEXT:%.*]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp ne i32 [[SUM_NEXT]], 4
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[BACKEDGE_LOOP_CRIT_EDGE:%.*]], label [[DONE:%.*]]
; CHECK: backedge.loop_crit_edge:
; CHECK-NEXT: unreachable
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
br label %loop
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 4, %sum
%is.positive = icmp sgt i32 %sub, 0
br i1 %is.positive, label %if.true, label %if.false
if.true:
br i1 %cond, label %if.true.1, label %if.true.2
if.true.1:
br label %backedge
if.true.2:
br label %backedge
if.false: ; preds = %loop
br i1 %cond2, label %if.false.1, label %if.false.2
if.false.1:
br label %backedge
if.false.2:
br label %backedge
backedge:
%merge.phi = phi i32 [ 0, %if.false.1 ], [ 0, %if.false.2 ], [ undef, %if.true.1 ], [ undef, %if.true.2 ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp ne i32 %sum.next, 4
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
; TODO: We can break the backedge here.
define i32 @test_select(i32 %limit) {
; CHECK-LABEL: @test_select(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[LOOP_GUARD:%.*]] = icmp sgt i32 [[LIMIT:%.*]], 0
; CHECK-NEXT: br i1 [[LOOP_GUARD]], label [[LOOP_PREHEADER:%.*]], label [[FAILURE:%.*]]
; CHECK: loop.preheader:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ [[SUM_NEXT:%.*]], [[LOOP]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 [[LIMIT]], [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: [[SEL:%.*]] = select i1 [[IS_POSITIVE]], i32 [[SUB]], i32 0
; CHECK-NEXT: [[SUM_NEXT]] = add i32 [[SUM]], [[SEL]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp ne i32 [[SUM_NEXT]], [[LIMIT]]
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[DONE:%.*]]
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[LOOP]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
%loop_guard = icmp sgt i32 %limit, 0
br i1 %loop_guard, label %loop, label %failure
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %loop ]
%sub = sub i32 %limit, %sum
%is.positive = icmp sgt i32 %sub, 0
%sel = select i1 %is.positive, i32 %sub, i32 0
%sum.next = add i32 %sum, %sel
%loop.cond = icmp ne i32 %sum.next, %limit
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %loop ]
ret i32 %sum.next.lcssa
failure:
unreachable
}
; TODO: We can break the backedge here.
define i32 @test_select_const(i32 %x) {
; CHECK-LABEL: @test_select_const(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[SUM:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[SUM_NEXT:%.*]], [[BACKEDGE:%.*]] ]
; CHECK-NEXT: [[SUB:%.*]] = sub i32 4, [[SUM]]
; CHECK-NEXT: [[IS_POSITIVE:%.*]] = icmp sgt i32 [[SUB]], 0
; CHECK-NEXT: [[SEL:%.*]] = select i1 [[IS_POSITIVE]], i32 [[SUB]], i32 [[X:%.*]]
; CHECK-NEXT: [[SEL_COND:%.*]] = icmp sgt i32 [[SEL]], 0
; CHECK-NEXT: br i1 [[SEL_COND]], label [[BACKEDGE]], label [[IF_FALSE:%.*]]
; CHECK: if.false:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[MERGE_PHI:%.*]] = phi i32 [ 0, [[IF_FALSE]] ], [ [[SUB]], [[LOOP]] ]
; CHECK-NEXT: [[SUM_NEXT]] = add i32 [[SUM]], [[MERGE_PHI]]
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp ne i32 [[SUM_NEXT]], 4
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[DONE:%.*]]
; CHECK: done:
; CHECK-NEXT: [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[SUM_NEXT_LCSSA]]
;
entry:
br label %loop
loop: ; preds = %backedge, %entry
%sum = phi i32 [ 0, %entry ], [ %sum.next, %backedge ]
%sub = sub i32 4, %sum
%is.positive = icmp sgt i32 %sub, 0
%sel = select i1 %is.positive, i32 %sub, i32 %x
%sel.cond = icmp sgt i32 %sel, 0
br i1 %sel.cond, label %backedge, label %if.false
if.false: ; preds = %loop
br label %backedge
backedge: ; preds = %if.false, %loop
%merge.phi = phi i32 [ 0, %if.false ], [ %sub, %loop ]
%sum.next = add i32 %sum, %merge.phi
%loop.cond = icmp ne i32 %sum.next, 4
br i1 %loop.cond, label %loop, label %done
done: ; preds = %backedge
%sum.next.lcssa = phi i32 [ %sum.next, %backedge ]
ret i32 %sum.next.lcssa
}
Reference in New Issue View Git Blame Copy Permalink