From d5e82c9f686f6c8e2feabfe753258f9fc13d980f Mon Sep 17 00:00:00 2001 From: Richard Biener Date: Fri, 29 Nov 2019 08:05:03 +0000 Subject: [PATCH] re PR tree-optimization/92704 (ICE: Segmentation fault (in process_bb)) 2019-11-29 Richard Biener PR tree-optimization/92704 * tree-if-conv.c (combine_blocks): Deal with virtual PHIs in loops performing only loads. * gcc.dg/torture/pr92704.c: New testcase. From-SVN: r278828 --- gcc/ChangeLog | 6 ++++++ gcc/testsuite/ChangeLog | 5 +++++ gcc/testsuite/gcc.dg/torture/pr92704.c | 24 ++++++++++++++++++++++++ gcc/tree-if-conv.c | 9 +++++++++ 4 files changed, 44 insertions(+) create mode 100644 gcc/testsuite/gcc.dg/torture/pr92704.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index b89f404a8b8..1ef3bc2de74 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2019-11-29 Richard Biener + + PR tree-optimization/92704 + * tree-if-conv.c (combine_blocks): Deal with virtual PHIs + in loops performing only loads. + 2019-11-29 Julian Brown * builtin-types.def (BT_DFLOAT32_PTR, BT_DFLOAT64_PTR, diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index f5bb0d2113e..b787896dd57 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2019-11-29 Richard Biener + + PR tree-optimization/92704 + * gcc.dg/torture/pr92704.c: New testcase. + 2019-11-29 Joseph Myers * objc.dg/attributes/gnu2x-attr-syntax-1.m: New test. diff --git a/gcc/testsuite/gcc.dg/torture/pr92704.c b/gcc/testsuite/gcc.dg/torture/pr92704.c new file mode 100644 index 00000000000..79994a39b54 --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr92704.c @@ -0,0 +1,24 @@ +/* { dg-do compile } */ +/* { dg-additional-options "-fexceptions -fnon-call-exceptions -fno-tree-dce -ftree-loop-if-convert" } */ +int zr, yx; + +void __attribute__ ((simd)) +oj (int rd, int q7) +{ + int wo = (__UINTPTR_TYPE__)&rd; + + while (q7 < 1) + { + int kv; + short int v3; + + for (v3 = 0; v3 < 82; v3 += 3) + { + } + + kv = zr ? 0 : v3; + yx = kv < rd; + zr = zr && yx; + ++q7; + } +} diff --git a/gcc/tree-if-conv.c b/gcc/tree-if-conv.c index 33d6cddb460..d2e40d43373 100644 --- a/gcc/tree-if-conv.c +++ b/gcc/tree-if-conv.c @@ -2624,6 +2624,11 @@ combine_blocks (class loop *loop) vphi = get_virtual_phi (bb); if (vphi) { + /* When there's just loads inside the loop a stray virtual + PHI merging the uses can appear, update last_vdef from + it. */ + if (!last_vdef) + last_vdef = gimple_phi_arg_def (vphi, 0); imm_use_iterator iter; use_operand_p use_p; gimple *use_stmt; @@ -2655,6 +2660,10 @@ combine_blocks (class loop *loop) if (gimple_vdef (stmt)) last_vdef = gimple_vdef (stmt); } + else + /* If this is the first load we arrive at update last_vdef + so we handle stray PHIs correctly. */ + last_vdef = gimple_vuse (stmt); if (predicated[i]) { ssa_op_iter i; -- 2.30.2