Hi!
The following testcase ICEs on i?86/x86_64 and aarch64, because gen_lowpart
(pointer to gen_lowpart_general at that spot) doesn't want to handle
SUBREG of SYMBOL_REF. Fixed by using a variant that doesn't ICE and forcing
the operand into a register if it can't be optimized without generating
instructions. This is similar to the case a few lines above, where we also
force_reg if simplify_subreg failed.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2016-03-11 Jakub Jelinek <ja...@redhat.com>
PR rtl-optimization/70174
* expmed.c (store_bit_field_using_insv): Use gen_lowpart_if_possible
followed by gen_lowpart on force_reg instead of just gen_lowpart.
* gcc.dg/pr70174.c: New test.
--- gcc/expmed.c.jj 2016-02-11 20:28:51.000000000 +0100
+++ gcc/expmed.c 2016-03-11 10:40:27.258719168 +0100
@@ -658,24 +658,28 @@ store_bit_field_using_insv (const extrac
{
if (GET_MODE_BITSIZE (GET_MODE (value)) >= bitsize)
{
+ rtx tmp;
/* Optimization: Don't bother really extending VALUE
if it has all the bits we will actually use. However,
if we must narrow it, be sure we do it correctly. */
if (GET_MODE_SIZE (GET_MODE (value)) < GET_MODE_SIZE (op_mode))
{
- rtx tmp;
-
tmp = simplify_subreg (op_mode, value1, GET_MODE (value), 0);
if (! tmp)
tmp = simplify_gen_subreg (op_mode,
force_reg (GET_MODE (value),
value1),
GET_MODE (value), 0);
- value1 = tmp;
}
else
- value1 = gen_lowpart (op_mode, value1);
+ {
+ tmp = gen_lowpart_if_possible (op_mode, value1);
+ if (! tmp)
+ tmp = gen_lowpart (op_mode, force_reg (GET_MODE (value),
+ value1));
+ }
+ value1 = tmp;
}
else if (CONST_INT_P (value))
value1 = gen_int_mode (INTVAL (value), op_mode);
--- gcc/testsuite/gcc.dg/pr70174.c.jj 2016-03-11 10:42:45.914894656 +0100
+++ gcc/testsuite/gcc.dg/pr70174.c 2016-03-11 10:42:31.000000000 +0100
@@ -0,0 +1,11 @@
+/* PR rtl-optimization/70174 */
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+
+struct S { int f : 4; } a;
+
+void
+foo (void)
+{
+ a.f = foo; /* { dg-warning "assignment makes integer from pointer without
a cast" } */
+}
Jakub
