From: Jakub Jelinek <jakub@redhat.com>
Date: Fri, 30 Aug 2019 11:38:28 +0000 (+0200)
Subject: backport: re PR rtl-optimization/89195 (Corrupted stack offset after combine)
X-Git-Tag: releases/gcc-7.5.0~262
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e8a5c7b37007b76733fcafb8b03e4a5407ebb03b;p=thirdparty%2Fgcc.git

backport: re PR rtl-optimization/89195 (Corrupted stack offset after combine)

	Backported from mainline
	2019-02-05  Jakub Jelinek  <jakub@redhat.com>

	PR rtl-optimization/89195
	* combine.c (make_extraction): For MEMs, don't extract bytes outside
	of the original MEM.

	* gcc.c-torture/execute/pr89195.c: New test.

From-SVN: r275099
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 824bedc31707..ff921609067c 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -3,6 +3,10 @@
 	Backported from mainline
 	2019-02-05  Jakub Jelinek  <jakub@redhat.com>
 
+	PR rtl-optimization/89195
+	* combine.c (make_extraction): For MEMs, don't extract bytes outside
+	of the original MEM.
+
 	PR target/89186
 	* optabs.c (prepare_cmp_insn): Pass x and y to
 	emit_block_comp_via_libcall rather than XEXP (x, 0) and XEXP (y, 0).
diff --git a/gcc/combine.c b/gcc/combine.c
index 56f7f4912343..685b0db62e58 100644
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -7481,6 +7481,7 @@ make_extraction (machine_mode mode, rtx inner, HOST_WIDE_INT pos,
 	      /* We can't do this if we are widening INNER_MODE (it
 		 may not be aligned, for one thing).  */
 	      && GET_MODE_PRECISION (inner_mode) >= GET_MODE_PRECISION (tmode)
+	      && pos + len <= GET_MODE_PRECISION (is_mode)
 	      && (inner_mode == tmode
 		  || (! mode_dependent_address_p (XEXP (inner, 0),
 						  MEM_ADDR_SPACE (inner))
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 8b5d6d16085a..063fbdbca951 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -3,6 +3,9 @@
 	Backported from mainline
 	2019-02-05  Jakub Jelinek  <jakub@redhat.com>
 
+	PR rtl-optimization/89195
+	* gcc.c-torture/execute/pr89195.c: New test.
+
 	PR target/89186
 	* g++.dg/ext/vector36.C: New test.
 
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr89195.c b/gcc/testsuite/gcc.c-torture/execute/pr89195.c
new file mode 100644
index 000000000000..017f5b4309aa
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr89195.c
@@ -0,0 +1,22 @@
+/* PR rtl-optimization/89195 */
+/* { dg-require-effective-target int32plus } */
+
+struct S { unsigned i : 24; };
+
+volatile unsigned char x;
+
+__attribute__((noipa)) int
+foo (struct S d) 
+{
+  return d.i & x;
+}
+
+int
+main ()
+{
+  struct S d = { 0x123456 };
+  x = 0x75;
+  if (foo (d) != (0x56 & 0x75))
+    __builtin_abort ();
+  return 0;
+}