From f4e426f7bd7df279cb7aaecd91d273d9b7db338d Mon Sep 17 00:00:00 2001 From: Richard Biener Date: Fri, 29 Jan 2021 11:17:42 +0100 Subject: [PATCH] tree-optimization/97627 - Avoid computing niters for fake edges This avoids computing niters information for fake edges. 2021-01-29 Bin Cheng Richard Biener PR tree-optimization/97627 * tree-ssa-loop-niter.c (number_of_iterations_exit_assumptions): Do not analyze fake edges. * g++.dg/pr97627.C: New testcase. --- gcc/testsuite/g++.dg/pr97627.C | 44 ++++++++++++++++++++++++++++++++++ gcc/tree-ssa-loop-niter.c | 5 ++++ 2 files changed, 49 insertions(+) create mode 100644 gcc/testsuite/g++.dg/pr97627.C diff --git a/gcc/testsuite/g++.dg/pr97627.C b/gcc/testsuite/g++.dg/pr97627.C new file mode 100644 index 00000000000..81466dc3b81 --- /dev/null +++ b/gcc/testsuite/g++.dg/pr97627.C @@ -0,0 +1,44 @@ +/* PR tree-optimization/97627. */ +/* { dg-do run } */ + +struct S { unsigned short x, y; } m = { 1, 0 }; + +__attribute__((noipa)) void +baz (int x, int y) +{ + if (x != 0 || y != 1) + __builtin_abort (); +} + +__attribute__((noipa)) void +bar () +{ + throw 1; +} + +void +foo () +{ + while (1) + { + int a = m.x + 1; + int b = m.y + 1; + for (int c = 0; c < a; c++) + for (int d = 0; d < b; d++) + baz (d, b); + bar (); + } +} + +int +main () +{ + try + { + foo (); + } + catch (int) + { + } + return 0; +} diff --git a/gcc/tree-ssa-loop-niter.c b/gcc/tree-ssa-loop-niter.c index 98978bcaa85..3817ec423e7 100644 --- a/gcc/tree-ssa-loop-niter.c +++ b/gcc/tree-ssa-loop-niter.c @@ -2407,6 +2407,11 @@ number_of_iterations_exit_assumptions (class loop *loop, edge exit, affine_iv iv0, iv1; bool safe; + /* The condition at a fake exit (if it exists) does not control its + execution. */ + if (exit->flags & EDGE_FAKE) + return false; + /* Nothing to analyze if the loop is known to be infinite. */ if (loop_constraint_set_p (loop, LOOP_C_INFINITE)) return false; -- 2.30.2