| ; RUN: opt -analyze -enable-new-pm=0 -scalar-evolution < %s | FileCheck %s |
| ; RUN: opt -disable-output "-passes=print<scalar-evolution>" < %s 2>&1 | FileCheck %s |
| |
| define void @test0(i32 %init) { |
| ; CHECK-LABEL: Classifying expressions for: @test0 |
| ; CHECK: Loop %loop: max backedge-taken count is 32 |
| entry: |
| br label %loop |
| |
| loop: |
| %iv = phi i32 [ %init, %entry ], [ %iv.shift, %loop ] |
| %iv.shift = lshr i32 %iv, 1 |
| %exit.cond = icmp eq i32 %iv, 0 |
| br i1 %exit.cond, label %leave, label %loop |
| |
| leave: |
| ret void |
| } |
| |
| define void @test1(i32 %init) { |
| ; CHECK-LABEL: Classifying expressions for: @test1 |
| ; CHECK: Loop %loop: max backedge-taken count is 32 |
| entry: |
| br label %loop |
| |
| loop: |
| %iv = phi i32 [ %init, %entry ], [ %iv.shift, %loop ] |
| %iv.shift = shl i32 %iv, 1 |
| %exit.cond = icmp eq i32 %iv, 0 |
| br i1 %exit.cond, label %leave, label %loop |
| |
| leave: |
| ret void |
| } |
| |
| define void @test2(i32 %init) { |
| ; CHECK-LABEL: Determining loop execution counts for: @test2 |
| ; CHECK: Loop %loop: Unpredictable max backedge-taken count. |
| |
| ; Unpredictable because %iv could "stabilize" to either -1 or 0, |
| ; depending on %init. |
| entry: |
| br label %loop |
| |
| loop: |
| %iv = phi i32 [ %init, %entry ], [ %iv.shift, %loop ] |
| %iv.shift = ashr i32 %iv, 1 |
| %exit.cond = icmp eq i32 %iv, 0 |
| br i1 %exit.cond, label %leave, label %loop |
| |
| leave: |
| ret void |
| } |
| |
| define void @test3(i32* %init.ptr) { |
| ; CHECK-LABEL: Determining loop execution counts for: @test3 |
| ; CHECK: Loop %loop: max backedge-taken count is 32 |
| entry: |
| %init = load i32, i32* %init.ptr, !range !0 |
| br label %loop |
| |
| loop: |
| %iv = phi i32 [ %init, %entry ], [ %iv.shift, %loop ] |
| %iv.shift = ashr i32 %iv, 1 |
| %exit.cond = icmp eq i32 %iv, 0 |
| br i1 %exit.cond, label %leave, label %loop |
| |
| leave: |
| ret void |
| } |
| |
| define void @test4(i32* %init.ptr) { |
| ; CHECK-LABEL: Classifying expressions for: @test4 |
| ; CHECK-LABEL: Loop %loop: max backedge-taken count is 32 |
| entry: |
| %init = load i32, i32* %init.ptr, !range !1 |
| br label %loop |
| |
| loop: |
| %iv = phi i32 [ %init, %entry ], [ %iv.shift, %loop ] |
| %iv.shift = ashr i32 %iv, 1 |
| %exit.cond = icmp eq i32 %iv, -1 |
| br i1 %exit.cond, label %leave, label %loop |
| |
| leave: |
| ret void |
| } |
| |
| define void @test5(i32* %init.ptr) { |
| ; CHECK-LABEL: Determining loop execution counts for: @test5 |
| ; CHECK: Loop %loop: Unpredictable max backedge-taken count. |
| |
| ; %iv will "stabilize" to -1, so this is an infinite loop |
| entry: |
| %init = load i32, i32* %init.ptr, !range !1 |
| br label %loop |
| |
| loop: |
| %iv = phi i32 [ %init, %entry ], [ %iv.shift, %loop ] |
| %iv.shift = ashr i32 %iv, 1 |
| %exit.cond = icmp eq i32 %iv, 0 |
| br i1 %exit.cond, label %leave, label %loop |
| |
| leave: |
| ret void |
| } |
| |
| define void @test6(i32 %init, i32 %shift.amt) { |
| ; CHECK-LABEL: Determining loop execution counts for: @test6 |
| ; CHECK: Loop %loop: Unpredictable max backedge-taken count. |
| |
| ; Potentially infinite loop, since %shift.amt could be 0 |
| entry: |
| br label %loop |
| |
| loop: |
| %iv = phi i32 [ %init, %entry ], [ %iv.shift, %loop ] |
| %iv.shift = lshr i32 %iv, %shift.amt |
| %exit.cond = icmp eq i32 %iv, 0 |
| br i1 %exit.cond, label %leave, label %loop |
| |
| leave: |
| ret void |
| } |
| |
| define void @test7(i32 %init) { |
| ; CHECK-LABEL: Classifying expressions for: @test7 |
| ; CHECK: Loop %loop: max backedge-taken count is 32 |
| |
| entry: |
| br label %loop |
| |
| loop: |
| %iv = phi i32 [ %init, %entry ], [ %iv.shift, %loop ] |
| %iv.shift = lshr i32 %iv, 1 |
| %exit.cond = icmp eq i32 %iv.shift, 0 |
| br i1 %exit.cond, label %leave, label %loop |
| |
| leave: |
| ret void |
| } |
| |
| define void @test8(i32 %init) { |
| ; CHECK-LABEL: Classifying expressions for: @test8 |
| ; CHECK: Loop %loop: Unpredictable max backedge-taken count. |
| |
| ; In this test case, %iv.test stabilizes to 127, not -1, so the loop |
| ; is infinite. |
| |
| entry: |
| br label %loop |
| |
| loop: |
| %iv = phi i32 [ %init, %entry ], [ %iv.shift, %loop ] |
| %iv.shift = ashr i32 %iv, 1 |
| %iv.test = lshr i32 %iv, 1 |
| %exit.cond = icmp eq i32 %iv.test, -1 |
| br i1 %exit.cond, label %leave, label %loop |
| |
| leave: |
| ret void |
| } |
| |
| define void @test9() { |
| ; CHECK-LABEL: Determining loop execution counts for: @test9 |
| ; CHECK: Loop %loop: Unpredictable max backedge-taken count. |
| |
| ; This is an infinite loop, make sure that it recognized as such. |
| |
| entry: |
| br label %loop |
| |
| leave: |
| ret void |
| |
| loop: |
| %iv = phi i32 [ -20, %entry ], [ %iv.shift, %loop ] |
| %iv.shift = ashr i32 %iv, 1 |
| %exit.cond = icmp sgt i32 %iv, -1 |
| br i1 %exit.cond, label %leave, label %loop |
| } |
| |
| !0 = !{i32 0, i32 50000} |
| !1 = !{i32 -5000, i32 -1} |