Hi all,
This PR is an ICE while bootstrapping GCC with Cortex-A8 tuning, which we also
get from the default ARMv7-A tuning.
The ldrd/strd peepholes were recently made more aggressive and in this case
they transform:
(insn 13 33 40 2 (set (mem/c:SI (plus:SI (reg/f:SI 11 fp)
(const_int -28 [0xffffffffffffffe4])) [3 d.num_comps+0 S4 A64])
(reg:SI 12 ip [orig:117 _20 ] [117])) "cp-demangle.c":32 632
{*arm_movsi_vfp}
(expr_list:REG_DEAD (reg:SI 12 ip [orig:117 _20 ] [117])
(nil)))
(insn 40 13 39 2 (set (mem/f/c:SI (plus:SI (reg/f:SI 11 fp)
(const_int -24 [0xffffffffffffffe8])) [2 d.subs+0 S4 A32])
(reg/f:SI 13 sp)) "cp-demangle.c":51 632 {*arm_movsi_vfp}
(nil))
into:
(insn 68 33 39 2 (set (mem/c:DI (plus:SI (reg/f:SI 11 fp)
(const_int -28 [0xffffffffffffffe4])) [3 d.num_comps+0 S8 A64])
(reg:DI 12 ip)) "cp-demangle.c":51 -1
(nil))
This is okay, but the *movdi_vfp_cortexa8 pattern doesn't deal with the IP
being the source
of the store. The reason is that when the LDRD/STRD peepholes and machinery was
introduced back in r197530
it created the 'q' constraint which should be used for the register operands of
the DImode stores and loads
('q' means CORE_REGS when LDRD/STRD is enabled in ARM mode and GENERAL_REGS
otherwise). That revision
updated the movdi_vfp pattern to use it in alternatives 4,5,6 but neglected to
udpate the Cortex-A8-specific
pattern. This is a sign that we should perhaps get rid of this special-cased
pattern at some point, but for now
this simple patch updates the appropriate alternatives to use the 'q'
constraint so that output_move_double
can output the correct LDRD/STRD instruction.
Bootstrapped on arm-none-linux-gnueabihf with --with-arch=armv7-a that
exercises this code (bootstrap currently fails
without this patch) and tested with /-mtune=cortex-a8.
Ok for trunk?
Thanks,
Kyrill
2016-11-22 Kyrylo Tkachov <kyrylo.tkac...@arm.com>
PR target/78439
* config/arm/vfp.md (*movdi_vfp_cortexa8): Use 'q' constraints for the
register operand in alternatives 4,5,6.
2016-11-22 Kyrylo Tkachov <kyrylo.tkac...@arm.com>
PR target/78439
* gcc.c-torture/compile/pr78439.c: New test.
commit 600526ea992fa58f87e6b0b4f821f4a2dfd0fa7a
Author: Kyrylo Tkachov <kyrylo.tkac...@arm.com>
Date: Mon Nov 21 12:00:20 2016 +0000
[ARM] PR target/78439: Update movdi constraints for Cortex-A8 tuning to handled LDRD/STRD
diff --git a/gcc/config/arm/vfp.md b/gcc/config/arm/vfp.md
index 2051f10..ce56e16 100644
--- a/gcc/config/arm/vfp.md
+++ b/gcc/config/arm/vfp.md
@@ -355,8 +355,8 @@ (define_insn "*movdi_vfp"
)
(define_insn "*movdi_vfp_cortexa8"
- [(set (match_operand:DI 0 "nonimmediate_di_operand" "=r,r,r,r,r,r,m,w,!r,w,w, Uv")
- (match_operand:DI 1 "di_operand" "r,rDa,Db,Dc,mi,mi,r,r,w,w,Uvi,w"))]
+ [(set (match_operand:DI 0 "nonimmediate_di_operand" "=r,r,r,r,q,q,m,w,!r,w,w, Uv")
+ (match_operand:DI 1 "di_operand" "r,rDa,Db,Dc,mi,mi,q,r,w,w,Uvi,w"))]
"TARGET_32BIT && TARGET_HARD_FLOAT && arm_tune == TARGET_CPU_cortexa8
&& ( register_operand (operands[0], DImode)
|| register_operand (operands[1], DImode))
diff --git a/gcc/testsuite/gcc.c-torture/compile/pr78439.c b/gcc/testsuite/gcc.c-torture/compile/pr78439.c
new file mode 100644
index 0000000..a8af86b
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr78439.c
@@ -0,0 +1,56 @@
+/* PR target/78439. */
+
+enum demangle_component_type
+{
+ DEMANGLE_COMPONENT_THROW_SPEC
+};
+struct demangle_component
+{
+ enum demangle_component_type type;
+ struct
+ {
+ struct
+ {
+ struct demangle_component *left;
+ struct demangle_component *right;
+ };
+ };
+};
+
+int a, b;
+
+struct d_info
+{
+ struct demangle_component *comps;
+ int next_comp;
+ int num_comps;
+ struct demangle_component *subs;
+ int num_subs;
+ int is_conversion;
+};
+
+void
+fn1 (int p1, struct d_info *p2)
+{
+ p2->num_comps = 2 * p1;
+ p2->next_comp = p2->num_subs = p1;
+ p2->is_conversion = 0;
+}
+
+int fn3 (int *);
+void fn4 (struct d_info *, int);
+
+void
+fn2 ()
+{
+ int c;
+ struct d_info d;
+ b = 0;
+ c = fn3 (&a);
+ fn1 (c, &d);
+ struct demangle_component e[d.num_comps];
+ struct demangle_component *f[d.num_subs];
+ d.comps = e;
+ d.subs = (struct demangle_component *) f;
+ fn4 (&d, 1);
+}
