From: Bernd Edlinger <bernd.edlinger@hotmail.de>
Date: Wed, 21 Apr 2021 12:13:04 +0000 (+0200)
Subject: Fix target/100106 ICE in gen_movdi
X-Git-Tag: basepoints/gcc-13~8150
X-Git-Url: https://gcc.gnu.org/git/?a=commitdiff_plain;h=c33db31d9ad96f6414460315c12b4b505fad5dd7;p=gcc.git

Fix target/100106 ICE in gen_movdi

As the test case shows, the outer mode may have a higher alignment
requirement than the inner mode here.

2021-04-27  Bernd Edlinger  <bernd.edlinger@hotmail.de>

	PR target/100106
	* simplify-rtx.c (simplify_context::simplify_subreg): Check the
	memory alignment for the outer mode.

	* gcc.c-torture/compile/pr100106.c: New testcase.
---

diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c
index d13c390a20cc..ad3b7b2d9d0e 100644
--- a/gcc/simplify-rtx.c
+++ b/gcc/simplify-rtx.c
@@ -7217,6 +7217,7 @@ simplify_context::simplify_subreg (machine_mode outermode, rtx op,
          have instruction to move the whole thing.  */
       && (! MEM_VOLATILE_P (op)
 	  || ! have_insn_for (SET, innermode))
+      && !(STRICT_ALIGNMENT && MEM_ALIGN (op) < GET_MODE_ALIGNMENT (outermode))
       && known_le (outersize, innersize))
     return adjust_address_nv (op, outermode, byte);
 
diff --git a/gcc/testsuite/gcc.c-torture/compile/pr100106.c b/gcc/testsuite/gcc.c-torture/compile/pr100106.c
new file mode 100644
index 000000000000..7f98b4f992e0
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr100106.c
@@ -0,0 +1,11 @@
+union a {
+  float _Complex b;
+  long long c;
+};
+
+void g(union a);
+
+void e() {
+  union a f = {1.0f};
+  g(f);
+}