From: Kwok Cheung Yeung <kcy@codesourcery.com>
Date: Thu, 14 Apr 2022 20:21:11 +0000 (+0100)
Subject: Fix ICE in OpenACC kernel testcases
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0ad06e951e9ae93ad039325e58a569e56b3c610d;p=thirdparty%2Fgcc.git

Fix ICE in OpenACC kernel testcases

This is due to sequences like this occurring:

<bb 11> :
  .data_dep.8_27 = .UNIQUE (OACC_TAIL_MARK, .data_dep.8_16, 2);

<bb 12> :
  .data_dep.8_29 = .UNIQUE (OACC_JOIN, .data_dep.8_27, -1);
...
<bb 15> :
  .UNIQUE (OACC_TAIL_MARK, .data_dep.8_33);

The final tail mark has no LHS, causing code that assumes its presence to
segfault.  The LHS and the assignment appear to have been removed as dead
code by the cddce1 stage.

Fixed by checking for the presence of the LHS before using it.

2022-04-14  Kwok Cheung Yeung  <kcy@codesourcery.com>

	gcc/
	* graphite-oacc.cc (find_oacc_tail_marks): Check that data_dep is
	non-NULL before testing it.
	(reduction_use_in_outer_loop_p): Likewise.
---

diff --git a/gcc/ChangeLog.omp b/gcc/ChangeLog.omp
index eba48717ee8d..1a9d3c507b55 100644
--- a/gcc/ChangeLog.omp
+++ b/gcc/ChangeLog.omp
@@ -1,3 +1,9 @@
+2022-04-14  Kwok Cheung Yeung  <kcy@codesourcery.com>
+
+	* graphite-oacc.cc (find_oacc_tail_marks): Check that data_dep is
+	non-NULL before testing it.
+	(reduction_use_in_outer_loop_p): Likewise.
+
 2022-05-12  Jakub Jelinek  <jakub@redhat.com>
 
 	Backport from mainline:
diff --git a/gcc/graphite-oacc.cc b/gcc/graphite-oacc.cc
index 6ba5d0f293a1..3ca13597a5f1 100644
--- a/gcc/graphite-oacc.cc
+++ b/gcc/graphite-oacc.cc
@@ -253,7 +253,7 @@ find_oacc_tail_marks (loop_p loop)
   tree data_dep = gimple_call_lhs (top_tail_mark);
   gimple *stmt = top_tail_mark;
 
-  while (has_single_use (data_dep))
+  while (data_dep && has_single_use (data_dep))
     {
       use_operand_p use_p;
       single_imm_use (data_dep, &use_p, &stmt);
@@ -313,7 +313,7 @@ reduction_use_in_outer_loop_p (gcall *call)
   /* The IFN_GOACC_REDUCTION_CALLS are linked in a chain through
      immediate uses. Move to the end of this chain. */
   gimple *stmt = call;
-  while (has_single_use (data_dep))
+  while (data_dep && has_single_use (data_dep))
     {
       use_operand_p use_p;
       single_imm_use (data_dep, &use_p, &stmt);