From f9aa39b0cfe55ad9964ef4ca06200f37b80769be Mon Sep 17 00:00:00 2001 From: Diego Novillo Date: Tue, 8 Sep 2015 19:22:17 +0000 Subject: Fix PR 24723 - Handle 0-mass backedges in irreducible loops This corner case happens when we have an irreducible SCC that is deeply nested. As we work down the tree, the backedge masses start getting smaller and smaller until we reach one that is down to 0. Since we distribute the incoming mass using the backedge masses as weight, the distributor does not allow zero weights. So, we simply ignore them (which will just use the weights of the non-zero nodes). llvm-svn: 247050 --- .../BlockFrequencyInfo/irreducible_loop_crash.ll | 155 +++++++++++++++++++++ 1 file changed, 155 insertions(+) create mode 100644 llvm/test/Analysis/BlockFrequencyInfo/irreducible_loop_crash.ll (limited to 'llvm/test/Analysis/BlockFrequencyInfo/irreducible_loop_crash.ll') diff --git a/llvm/test/Analysis/BlockFrequencyInfo/irreducible_loop_crash.ll b/llvm/test/Analysis/BlockFrequencyInfo/irreducible_loop_crash.ll new file mode 100644 index 00000000000..2bcd088dd16 --- /dev/null +++ b/llvm/test/Analysis/BlockFrequencyInfo/irreducible_loop_crash.ll @@ -0,0 +1,155 @@ +; RUN: opt < %s -analyze -block-freq + +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +define void @fn1(i32* %f) { +entry: + %tobool7 = icmp eq i32 undef, 0 + br i1 undef, label %if.end.12, label %for.body.5 + +for.inc: + store i32 undef, i32* %f, align 4 + br label %for.body.5 + +for.body.5: ; preds = %for.cond.4.preheader + br i1 %tobool7, label %for.inc.9, label %for.inc + +for.inc.9: ; preds = %for.body.5 + br i1 %tobool7, label %for.inc.9.1, label %for.inc + +if.end.12: ; preds = %if.end.12, %for.body + br i1 undef, label %for.end.17, label %for.inc + +for.end.17: ; preds = %entry + ret void + +for.inc.9.1: ; preds = %for.inc.9 + br i1 %tobool7, label %for.inc.9.2, label %for.inc + +for.inc.9.2: ; preds = %for.inc.9.1 + br i1 %tobool7, label %for.inc.9.3, label %for.inc + +for.inc.9.3: ; preds = %for.inc.9.2 + br i1 %tobool7, label %for.inc.9.4, label %for.inc + +for.inc.9.4: ; preds = %for.inc.9.3 + br i1 %tobool7, label %for.inc.9.5, label %for.inc + +for.inc.9.5: ; preds = %for.inc.9.4 + br i1 %tobool7, label %for.inc.9.6, label %for.inc + +for.inc.9.6: ; preds = %for.inc.9.5 + br i1 %tobool7, label %for.inc.9.7, label %for.inc + +for.inc.9.7: ; preds = %for.inc.9.6 + br i1 %tobool7, label %for.inc.9.8, label %for.inc + +for.inc.9.8: ; preds = %for.inc.9.7 + br i1 %tobool7, label %for.inc.9.9, label %for.inc + +for.inc.9.9: ; preds = %for.inc.9.8 + br i1 %tobool7, label %for.inc.9.10, label %for.inc + +for.inc.9.10: ; preds = %for.inc.9.9 + br i1 %tobool7, label %for.inc.9.11, label %for.inc + +for.inc.9.11: ; preds = %for.inc.9.10 + br i1 %tobool7, label %for.inc.9.12, label %for.inc + +for.inc.9.12: ; preds = %for.inc.9.11 + br i1 %tobool7, label %for.inc.9.13, label %for.inc + +for.inc.9.13: ; preds = %for.inc.9.12 + br i1 %tobool7, label %for.inc.9.14, label %for.inc + +for.inc.9.14: ; preds = %for.inc.9.13 + br i1 %tobool7, label %for.inc.9.15, label %for.inc + +for.inc.9.15: ; preds = %for.inc.9.14 + br i1 %tobool7, label %for.inc.9.16, label %for.inc + +for.inc.9.16: ; preds = %for.inc.9.15 + br i1 %tobool7, label %for.inc.9.17, label %for.inc + +for.inc.9.17: ; preds = %for.inc.9.16 + br i1 %tobool7, label %for.inc.9.18, label %for.inc + +for.inc.9.18: ; preds = %for.inc.9.17 + br i1 %tobool7, label %for.inc.9.19, label %for.inc + +for.inc.9.19: ; preds = %for.inc.9.18 + br i1 %tobool7, label %for.inc.9.20, label %for.inc + +for.inc.9.20: ; preds = %for.inc.9.19 + br i1 %tobool7, label %for.inc.9.21, label %for.inc + +for.inc.9.21: ; preds = %for.inc.9.20 + br i1 %tobool7, label %for.inc.9.22, label %for.inc + +for.inc.9.22: ; preds = %for.inc.9.21 + br i1 %tobool7, label %for.inc.9.23, label %for.inc + +for.inc.9.23: ; preds = %for.inc.9.22 + br i1 %tobool7, label %for.inc.9.24, label %for.inc + +for.inc.9.24: ; preds = %for.inc.9.23 + br i1 %tobool7, label %for.inc.9.25, label %for.inc + +for.inc.9.25: ; preds = %for.inc.9.24 + br i1 %tobool7, label %for.inc.9.26, label %for.inc + +for.inc.9.26: ; preds = %for.inc.9.25 + br i1 %tobool7, label %for.inc.9.27, label %for.inc + +for.inc.9.27: ; preds = %for.inc.9.26 + br i1 %tobool7, label %for.inc.9.28, label %for.inc + +for.inc.9.28: ; preds = %for.inc.9.27 + br i1 %tobool7, label %for.inc.9.29, label %for.inc + +for.inc.9.29: ; preds = %for.inc.9.28 + br i1 %tobool7, label %for.inc.9.30, label %for.inc + +for.inc.9.30: ; preds = %for.inc.9.29 + br i1 %tobool7, label %for.inc.9.31, label %for.inc + +for.inc.9.31: ; preds = %for.inc.9.30 + br i1 %tobool7, label %for.inc.9.32, label %for.inc + +for.inc.9.32: ; preds = %for.inc.9.31 + br i1 %tobool7, label %for.inc.9.33, label %for.inc + +for.inc.9.33: ; preds = %for.inc.9.32 + br i1 %tobool7, label %for.inc.9.34, label %for.inc + +for.inc.9.34: ; preds = %for.inc.9.33 + br i1 %tobool7, label %for.inc.9.35, label %for.inc + +for.inc.9.35: ; preds = %for.inc.9.34 + br i1 %tobool7, label %for.inc.9.36, label %for.inc + +for.inc.9.36: ; preds = %for.inc.9.35 + br i1 %tobool7, label %for.inc.9.37, label %for.inc + +for.inc.9.37: ; preds = %for.inc.9.36 + br i1 %tobool7, label %for.inc.9.38, label %for.inc + +for.inc.9.38: ; preds = %for.inc.9.37 + br i1 %tobool7, label %for.inc.9.39, label %for.inc + +for.inc.9.39: ; preds = %for.inc.9.38 + br i1 %tobool7, label %for.inc.9.40, label %for.inc + +for.inc.9.40: ; preds = %for.inc.9.39 + br i1 %tobool7, label %for.inc.9.41, label %for.inc + +for.inc.9.41: ; preds = %for.inc.9.40 + br i1 %tobool7, label %for.inc.9.42, label %for.inc + +for.inc.9.42: ; preds = %for.inc.9.41 + br i1 %tobool7, label %for.inc.9.43, label %for.inc + +for.inc.9.43: ; preds = %for.inc.9.42 + br i1 %tobool7, label %if.end.12, label %for.inc +} -- cgit v1.2.3