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diff --git a/test/Analysis/BlockFrequencyInfo/irreducible.ll b/test/Analysis/BlockFrequencyInfo/irreducible.ll
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--- a/test/Analysis/BlockFrequencyInfo/irreducible.ll
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-; RUN: opt < %s -analyze -block-freq | FileCheck %s
-
-; A loop with multiple exits should be handled correctly.
-;
-; CHECK-LABEL: Printing analysis {{.*}} for function 'multiexit':
-; CHECK-NEXT: block-frequency-info: multiexit
-define void @multiexit(i32 %a) {
-; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
-entry:
- br label %loop.1
-
-; CHECK-NEXT: loop.1: float = 1.333{{3*}},
-loop.1:
- %i = phi i32 [ 0, %entry ], [ %inc.2, %loop.2 ]
- call void @f(i32 %i)
- %inc.1 = add i32 %i, 1
- %cmp.1 = icmp ugt i32 %inc.1, %a
- br i1 %cmp.1, label %exit.1, label %loop.2, !prof !0
-
-; CHECK-NEXT: loop.2: float = 0.666{{6*7}},
-loop.2:
- call void @g(i32 %inc.1)
- %inc.2 = add i32 %inc.1, 1
- %cmp.2 = icmp ugt i32 %inc.2, %a
- br i1 %cmp.2, label %exit.2, label %loop.1, !prof !1
-
-; CHECK-NEXT: exit.1: float = 0.666{{6*7}},
-exit.1:
- call void @h(i32 %inc.1)
- br label %return
-
-; CHECK-NEXT: exit.2: float = 0.333{{3*}},
-exit.2:
- call void @i(i32 %inc.2)
- br label %return
-
-; CHECK-NEXT: return: float = 1.0, int = [[ENTRY]]
-return:
- ret void
-}
-
-declare void @f(i32 %x)
-declare void @g(i32 %x)
-declare void @h(i32 %x)
-declare void @i(i32 %x)
-
-!0 = metadata !{metadata !"branch_weights", i32 3, i32 3}
-!1 = metadata !{metadata !"branch_weights", i32 5, i32 5}
-
-; The current BlockFrequencyInfo algorithm doesn't handle multiple entrances
-; into a loop very well. The frequencies assigned to blocks in the loop are
-; predictable (and not absurd), but also not correct and therefore not worth
-; testing.
-;
-; There are two testcases below.
-;
-; For each testcase, I use a CHECK-NEXT/NOT combo like an XFAIL with the
-; granularity of a single check. If/when this behaviour is fixed, we'll know
-; about it, and the test should be updated.
-;
-; Testcase #1
-; ===========
-;
-; In this case c1 and c2 should have frequencies of 15/7 and 13/7,
-; respectively. To calculate this, consider assigning 1.0 to entry, and
-; distributing frequency iteratively (to infinity). At the first iteration,
-; entry gives 3/4 to c1 and 1/4 to c2. At every step after, c1 and c2 give 3/4
-; of what they have to each other. Somehow, all of it comes out to exit.
-;
-; c1 = 3/4 + 1/4*3/4 + 3/4*3^2/4^2 + 1/4*3^3/4^3 + 3/4*3^3/4^3 + ...
-; c2 = 1/4 + 3/4*3/4 + 1/4*3^2/4^2 + 3/4*3^3/4^3 + 1/4*3^3/4^3 + ...
-;
-; Simplify by splitting up the odd and even terms of the series and taking out
-; factors so that the infite series matches:
-;
-; c1 = 3/4 *(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
-; + 3/16*(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
-; c2 = 1/4 *(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
-; + 9/16*(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
-;
-; c1 = 15/16*(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
-; c2 = 13/16*(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
-;
-; Since this geometric series sums to 16/7:
-;
-; c1 = 15/7
-; c2 = 13/7
-;
-; If we treat c1 and c2 as members of the same loop, the exit frequency of the
-; loop as a whole is 1/4, so the loop scale should be 4. Summing c1 and c2
-; gives 28/7, or 4.0, which is nice confirmation of the math above.
-;
-; However, assuming c1 precedes c2 in reverse post-order, the current algorithm
-; returns 3/4 and 13/16, respectively. LoopInfo ignores edges between loops
-; (and doesn't see any loops here at all), and -block-freq ignores the
-; irreducible edge from c2 to c1.
-;
-; CHECK-LABEL: Printing analysis {{.*}} for function 'multientry':
-; CHECK-NEXT: block-frequency-info: multientry
-define void @multientry(i32 %a) {
-; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
-entry:
- %choose = call i32 @choose(i32 %a)
- %compare = icmp ugt i32 %choose, %a
- br i1 %compare, label %c1, label %c2, !prof !2
-
-; This is like a single-line XFAIL (see above).
-; CHECK-NEXT: c1:
-; CHECK-NOT: float = 2.142857{{[0-9]*}},
-c1:
- %i1 = phi i32 [ %a, %entry ], [ %i2.inc, %c2 ]
- %i1.inc = add i32 %i1, 1
- %choose1 = call i32 @choose(i32 %i1)
- %compare1 = icmp ugt i32 %choose1, %a
- br i1 %compare1, label %c2, label %exit, !prof !2
-
-; This is like a single-line XFAIL (see above).
-; CHECK-NEXT: c2:
-; CHECK-NOT: float = 1.857142{{[0-9]*}},
-c2:
- %i2 = phi i32 [ %a, %entry ], [ %i1.inc, %c1 ]
- %i2.inc = add i32 %i2, 1
- %choose2 = call i32 @choose(i32 %i2)
- %compare2 = icmp ugt i32 %choose2, %a
- br i1 %compare2, label %c1, label %exit, !prof !2
-
-; We still shouldn't lose any frequency.
-; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
-exit:
- ret void
-}
-
-; Testcase #2
-; ===========
-;
-; In this case c1 and c2 should be treated as equals in a single loop. The
-; exit frequency is 1/3, so the scaling factor for the loop should be 3.0. The
-; loop is entered 2/3 of the time, and c1 and c2 split the total loop frequency
-; evenly (1/2), so they should each have frequencies of 1.0 (3.0*2/3*1/2).
-; Another way of computing this result is by assigning 1.0 to entry and showing
-; that c1 and c2 should accumulate frequencies of:
-;
-; 1/3 + 2/9 + 4/27 + 8/81 + ...
-; 2^0/3^1 + 2^1/3^2 + 2^2/3^3 + 2^3/3^4 + ...
-;
-; At the first step, c1 and c2 each get 1/3 of the entry. At each subsequent
-; step, c1 and c2 each get 1/3 of what's left in c1 and c2 combined. This
-; infinite series sums to 1.
-;
-; However, assuming c1 precedes c2 in reverse post-order, the current algorithm
-; returns 1/2 and 3/4, respectively. LoopInfo ignores edges between loops (and
-; treats c1 and c2 as self-loops only), and -block-freq ignores the irreducible
-; edge from c2 to c1.
-;
-; Below I use a CHECK-NEXT/NOT combo like an XFAIL with the granularity of a
-; single check. If/when this behaviour is fixed, we'll know about it, and the
-; test should be updated.
-;
-; CHECK-LABEL: Printing analysis {{.*}} for function 'crossloops':
-; CHECK-NEXT: block-frequency-info: crossloops
-define void @crossloops(i32 %a) {
-; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
-entry:
- %choose = call i32 @choose(i32 %a)
- switch i32 %choose, label %exit [ i32 1, label %c1
- i32 2, label %c2 ], !prof !3
-
-; This is like a single-line XFAIL (see above).
-; CHECK-NEXT: c1:
-; CHECK-NOT: float = 1.0,
-c1:
- %i1 = phi i32 [ %a, %entry ], [ %i1.inc, %c1 ], [ %i2.inc, %c2 ]
- %i1.inc = add i32 %i1, 1
- %choose1 = call i32 @choose(i32 %i1)
- switch i32 %choose1, label %exit [ i32 1, label %c1
- i32 2, label %c2 ], !prof !3
-
-; This is like a single-line XFAIL (see above).
-; CHECK-NEXT: c2:
-; CHECK-NOT: float = 1.0,
-c2:
- %i2 = phi i32 [ %a, %entry ], [ %i1.inc, %c1 ], [ %i2.inc, %c2 ]
- %i2.inc = add i32 %i2, 1
- %choose2 = call i32 @choose(i32 %i2)
- switch i32 %choose2, label %exit [ i32 1, label %c1
- i32 2, label %c2 ], !prof !3
-
-; We still shouldn't lose any frequency.
-; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
-exit:
- ret void
-}
-
-declare i32 @choose(i32)
-
-!2 = metadata !{metadata !"branch_weights", i32 3, i32 1}
-!3 = metadata !{metadata !"branch_weights", i32 2, i32 2, i32 2}