public inbox for gcc-cvs@sourceware.org
help / color / mirror / Atom feed
* [gcc r13-6420] analyzer: fix uninit false +ves reading from DECL_HARD_REGISTER [PR108968]
@ 2023-03-02 19:02 David Malcolm
0 siblings, 0 replies; only message in thread
From: David Malcolm @ 2023-03-02 19:02 UTC (permalink / raw)
To: gcc-cvs
https://gcc.gnu.org/g:20bd258d0fa09837b3a93478ef92d8789cbcd442
commit r13-6420-g20bd258d0fa09837b3a93478ef92d8789cbcd442
Author: David Malcolm <dmalcolm@redhat.com>
Date: Thu Mar 2 14:01:19 2023 -0500
analyzer: fix uninit false +ves reading from DECL_HARD_REGISTER [PR108968]
gcc/analyzer/ChangeLog:
PR analyzer/108968
* region-model.cc (region_model::get_rvalue_1): Handle VAR_DECLs
with a DECL_HARD_REGISTER by returning UNKNOWN.
gcc/testsuite/ChangeLog:
PR analyzer/108968
* gcc.dg/analyzer/uninit-pr108968-register.c: New test.
Signed-off-by: David Malcolm <dmalcolm@redhat.com>
Diff:
---
gcc/analyzer/region-model.cc | 9 ++++++++-
gcc/testsuite/gcc.dg/analyzer/uninit-pr108968-register.c | 9 +++++++++
2 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/gcc/analyzer/region-model.cc b/gcc/analyzer/region-model.cc
index 2187aecbe91..bf07cec2884 100644
--- a/gcc/analyzer/region-model.cc
+++ b/gcc/analyzer/region-model.cc
@@ -2203,9 +2203,16 @@ region_model::get_rvalue_1 (path_var pv, region_model_context *ctxt) const
return get_rvalue_for_bits (TREE_TYPE (expr), reg, bits, ctxt);
}
- case SSA_NAME:
case VAR_DECL:
+ if (DECL_HARD_REGISTER (pv.m_tree))
+ {
+ /* If it has a hard register, it doesn't have a memory region
+ and can't be referred to as an lvalue. */
+ return m_mgr->get_or_create_unknown_svalue (TREE_TYPE (pv.m_tree));
+ }
+ /* Fall through. */
case PARM_DECL:
+ case SSA_NAME:
case RESULT_DECL:
case ARRAY_REF:
{
diff --git a/gcc/testsuite/gcc.dg/analyzer/uninit-pr108968-register.c b/gcc/testsuite/gcc.dg/analyzer/uninit-pr108968-register.c
new file mode 100644
index 00000000000..a76c09e7b14
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/analyzer/uninit-pr108968-register.c
@@ -0,0 +1,9 @@
+/* { dg-do compile { target x86_64-*-* } } */
+
+#define STACK_SIZE 4096
+struct cpu_info {};
+struct cpu_info *get_cpu_info(void)
+{
+ register unsigned long sp asm("rsp");
+ return (struct cpu_info *)((sp | (STACK_SIZE - 1)) + 1) - 1; /* { dg-bogus "use of uninitialized value 'sp'" } */
+}
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2023-03-02 19:02 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-03-02 19:02 [gcc r13-6420] analyzer: fix uninit false +ves reading from DECL_HARD_REGISTER [PR108968] David Malcolm
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).