From: Kugan Vivekanandarajah <kvivekananda@nvidia.com>
Date: Fri, 9 Jan 2026 00:59:27 +0000 (+1100)
Subject: [Bug gcov-profile/123019][V3] Fix Virtual SSA ICE
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=83b3c80fac333c429d0d8a9f58d3d494c2ba305f;p=thirdparty%2Fgcc.git

[Bug gcov-profile/123019][V3] Fix Virtual SSA ICE

The bug is a stale Virtual SSA VDEF on calls to functions that have
been marked const or pure.

pure_const pass analyzes function rocksdb::y::y() and determines it has no side
effects and marks it as const.

At this point, existing call sites to y::y() in other functions still have:
   # .MEM_12 = VDEF <.MEM_11>   rocksdb::y::y (&l, _9);
The VDEF indicates the call modifies memory but now that y::y() is const,
this VDEF is stale

Later passes  after feedback_fnsplit SSA verification fails. Added fixup.

gcc/ChangeLog:

2026-01-07  Kugan Vivekanandarajah  <kvivekananda@nvidia.com>

	PR gcov-profile/123019
	* auto-profile.cc (auto_profile): Call execute_fixup_cfg.

Signed-off-by: Kugan Vivekanandarajah <kvivekananda@nvidia.com>
---

diff --git a/gcc/auto-profile.cc b/gcc/auto-profile.cc
index 06ea4015251..2434936a0a6 100644
--- a/gcc/auto-profile.cc
+++ b/gcc/auto-profile.cc
@@ -4567,6 +4567,11 @@ auto_profile (void)
 
     push_cfun (DECL_STRUCT_FUNCTION (node->decl));
 
+    /* Local pure-const may imply need to fixup the cfg.
+       This is similar to what is done in tree-profile.cc.  */
+    if ((execute_fixup_cfg () & TODO_cleanup_cfg))
+      cleanup_tree_cfg ();
+
     autofdo::afdo_annotate_cfg ();
     compute_function_frequency ();