With -O, gcc.c-torture/compile/simd-2.c ICEs with
internal compiler error: in simplify_binary_operation_1, at simplify-rtx.c:2666
on sh64. It didn't fail on revision 127620, so this is a 4.3 regression.
The backtrace with gdb looks like
#1 0x08388b7d in simplify_binary_operation (code=VEC_SELECT, mode=SFmode,
op0=0xa6a, op1=0x87d1c52) at ../../ORIG/trunk/gcc/simplify-rtx.c:2875
#2 0x086c6b05 in combine_simplify_rtx (x=0x40239888, op0_mode=SFmode,
in_dest=0) at ../../ORIG/trunk/gcc/combine.c:4706
#3 0x086c933a in subst (x=0x40239888, from=0x40234110, to=0x401a30c0,
in_dest=0, unique_copy=0) at ../../ORIG/trunk/gcc/combine.c:4541
and the first parameter of combine_simplify_rtx at #2 is:
(vec_select:SF (plus:SF (vec_select:SF (reg:V2SF 163)
(parallel [
(const_int 0 [0x0])
]))
(vec_select:SF (reg:V2SF 175)
(parallel [
(const_int 0 [0x0])
])))
(parallel [
(const_int 0 [0x0])
]))
simplify_binary_operation_1 checks if the first argument of vec_select
is VECTOR_MODE_P when the mode of vec_select is a scalar type:
case VEC_SELECT:
if (!VECTOR_MODE_P (mode))
{
gcc_assert (VECTOR_MODE_P (GET_MODE (trueop0)));
but the above rtl isn't. Thus the above gcc_assert fails.
It seems that combine optimization makes a rtl like
(vec_select:SF
(vec_select:V2SF
(vec_concat:V2SF
(vec_select:SF (reg:V2SF 187)
(parallel [
(const_int 1 [0x1])
]))
(plus:SF (vec_select:SF (reg:V2SF 163)
(parallel [
(const_int 0 [0x0])
]))
(vec_select:SF (reg:V2SF 175)
(parallel [
(const_int 0 [0x0])
]))))
(parallel [
(const_int 1 [0x1])
(const_int 0 [0x0])
]))
(parallel [
(const_int 0 [0x0])
]))
and simplify_binary_operation_1 simplifies it to
(vec_select:SF
(plus:SF (vec_select:SF (reg:V2SF 163)
(parallel [
(const_int 0 [0x0])
]))
(vec_select:SF (reg:V2SF 175)
(parallel [
(const_int 0 [0x0])
])))
(parallel [
(const_int 0 [0x0])
]))
with the code flow
case VEC_SELECT:
if (!VECTOR_MODE_P (mode))
{
gcc_assert (VECTOR_MODE_P (GET_MODE (trueop0)));
...
/* Extract a scalar element from a nested VEC_SELECT expression
(with optional nested VEC_CONCAT expression). Some targets
(i386) extract scalar element from a vector using chain of
nested VEC_SELECT expressions. When input operand is a memory
operand, this operation can be simplified to a simple scalar
load from an offseted memory address. */
if (GET_CODE (trueop0) == VEC_SELECT)
{
...
/* Handle the case when nested VEC_SELECT wraps VEC_CONCAT. */
if (GET_CODE (op0) == VEC_CONCAT)
...
tmp = gen_rtx_fmt_ee (code, mode,
tmp_op, gen_rtx_PARALLEL (VOIDmode, vec));
return tmp;
}
in the failed case.
Then at the another simplify_binary_operation_1 invocation, the last
rtl is considered a problematic one.
--
Summary: [4.3 Regression] ICE in simplify_binary_operation_1, at
simplify-rtx.c:2666 on sh64
Product: gcc
Version: 4.3.0
Status: UNCONFIRMED
Keywords: ice-on-valid-code
Severity: normal
Priority: P3
Component: target
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: kkojima at gcc dot gnu dot org
GCC target triplet: sh64-elf
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34155
