Hi! The following testcase ICEs when dumping details. When m_ssa_ranges vector is created, it is safe_grow_cleared (num_ssa_names), but when when some new SSA_NAME is added, we strangely grow it to num_ssa_names + 1 instead and later on the 3 argument dump method iterates from 1 to m_ssa_ranges.length () - 1 and uses ssa_name (x) on each; but because set_bb_range grew it one too much, ssa_name (m_ssa_ranges.length () - 1) might be after the end of the ssanames vector and ICE.
The fix grows the vector consistently only to num_ssa_names, doesn't waste time checking m_ssa_ranges[0] because there is no ssa_names (0), it is always NULL, before using ssa_name (x) checks if we'll need it at all (we check later if m_ssa_ranges[x] is non-NULL, so we might check it earlier as well) and also in the last loop iterates until m_ssa_ranges.length () rather than num_ssa_names, I don't see a reason for the inconsistency and in theory some SSA_NAME could be added without set_bb_range called for it and the vector could be shorter than the ssanames vector. To actually fix the ICE, either the first hunk or the last 2 hunks would be enough, but I think it doesn't hurt to change all the spots. Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? 2023-11-11 Jakub Jelinek <ja...@redhat.com> PR tree-optimization/111967 * gimple-range-cache.cc (block_range_cache::set_bb_range): Grow m_ssa_ranges to num_ssa_names rather than num_ssa_names + 1. (block_range_cache::dump): Iterate from 1 rather than 0. Don't use ssa_name (x) unless m_ssa_ranges[x] is non-NULL. Iterate to m_ssa_ranges.length () rather than num_ssa_names. * gcc.dg/tree-ssa/pr111967.c: New test. --- gcc/gimple-range-cache.cc.jj 2023-10-10 11:56:05.819220320 +0200 +++ gcc/gimple-range-cache.cc 2023-11-10 17:06:52.482867324 +0100 @@ -390,7 +390,7 @@ block_range_cache::set_bb_range (tree na { unsigned v = SSA_NAME_VERSION (name); if (v >= m_ssa_ranges.length ()) - m_ssa_ranges.safe_grow_cleared (num_ssa_names + 1); + m_ssa_ranges.safe_grow_cleared (num_ssa_names); if (!m_ssa_ranges[v]) { @@ -465,7 +465,7 @@ void block_range_cache::dump (FILE *f) { unsigned x; - for (x = 0; x < m_ssa_ranges.length (); ++x) + for (x = 1; x < m_ssa_ranges.length (); ++x) { if (m_ssa_ranges[x]) { @@ -487,11 +487,14 @@ block_range_cache::dump (FILE *f, basic_ bool summarize_varying = false; for (x = 1; x < m_ssa_ranges.length (); ++x) { + if (!m_ssa_ranges[x]) + continue; + if (!gimple_range_ssa_p (ssa_name (x))) continue; Value_Range r (TREE_TYPE (ssa_name (x))); - if (m_ssa_ranges[x] && m_ssa_ranges[x]->get_bb_range (r, bb)) + if (m_ssa_ranges[x]->get_bb_range (r, bb)) { if (!print_varying && r.varying_p ()) { @@ -508,13 +511,16 @@ block_range_cache::dump (FILE *f, basic_ if (summarize_varying) { fprintf (f, "VARYING_P on entry : "); - for (x = 1; x < num_ssa_names; ++x) + for (x = 1; x < m_ssa_ranges.length (); ++x) { + if (!m_ssa_ranges[x]) + continue; + if (!gimple_range_ssa_p (ssa_name (x))) continue; Value_Range r (TREE_TYPE (ssa_name (x))); - if (m_ssa_ranges[x] && m_ssa_ranges[x]->get_bb_range (r, bb)) + if (m_ssa_ranges[x]->get_bb_range (r, bb)) { if (r.varying_p ()) { --- gcc/testsuite/gcc.dg/tree-ssa/pr111967.c.jj 2023-11-10 16:45:54.006085324 +0100 +++ gcc/testsuite/gcc.dg/tree-ssa/pr111967.c 2023-11-10 17:03:17.257844360 +0100 @@ -0,0 +1,15 @@ +/* PR tree-optimization/111967 */ +/* { dg-do compile } */ +/* { dg-options "-O2 -fno-tree-forwprop -fdump-tree-evrp-all" } */ + +void bar (char *); +int a; +char *b; + +void +foo (void) +{ + long c = a & 3; + if (c) + bar (b + c); +} Jakub