simplify-rtx: Fix up simplify_logical_relational_operation for vector IOR [PR101008]

simplify_relational_operation callees typically return just const0_rtx
or const_true_rtx and then simplify_relational_operation attempts to fix
that up if the comparison result has vector mode, or floating mode,
or punt if it has scalar mode and vector mode operands (it doesn't know how
exactly to deal with the scalar masks).
But, simplify_logical_relational_operation has a special case, where
it attempts to fold (x < y) | (x >= y) etc. and if it determines it is
always true, it just returns const_true_rtx, without doing the dances that
simplify_relational_operation does.
That results in an ICE on the following testcase, where such folding happens
during expansion (of debug stmts into DEBUG_INSNs) and we ICE because
all of sudden a VOIDmode rtx appears where it expects a vector (V4SImode)
rtx.

The following patch fixes that by moving the adjustement into a separate
helper routine and using it from both simplify_relational_operation and
simplify_logical_relational_operation.

2021-06-11  Jakub Jelinek  <jakub@redhat.com>

	PR rtl-optimization/101008
	* simplify-rtx.c (relational_result): New function.
	(simplify_logical_relational_operation,
	simplify_relational_operation): Use it.

	* gcc.dg/pr101008.c: New test.
This commit is contained in:
Jakub Jelinek 2021-06-11 12:59:43 +02:00
parent a984da88a3
commit 4bdcdd8fa8
2 changed files with 67 additions and 46 deletions

View file

@ -2294,6 +2294,53 @@ comparison_code_valid_for_mode (enum rtx_code code, enum machine_mode mode)
gcc_unreachable ();
}
}
/* Canonicalize RES, a scalar const0_rtx/const_true_rtx to the right
false/true value of comparison with MODE where comparison operands
have CMP_MODE. */
static rtx
relational_result (machine_mode mode, machine_mode cmp_mode, rtx res)
{
if (SCALAR_FLOAT_MODE_P (mode))
{
if (res == const0_rtx)
return CONST0_RTX (mode);
#ifdef FLOAT_STORE_FLAG_VALUE
REAL_VALUE_TYPE val = FLOAT_STORE_FLAG_VALUE (mode);
return const_double_from_real_value (val, mode);
#else
return NULL_RTX;
#endif
}
if (VECTOR_MODE_P (mode))
{
if (res == const0_rtx)
return CONST0_RTX (mode);
#ifdef VECTOR_STORE_FLAG_VALUE
rtx val = VECTOR_STORE_FLAG_VALUE (mode);
if (val == NULL_RTX)
return NULL_RTX;
if (val == const1_rtx)
return CONST1_RTX (mode);
return gen_const_vec_duplicate (mode, val);
#else
return NULL_RTX;
#endif
}
/* For vector comparison with scalar int result, it is unknown
if the target means here a comparison into an integral bitmask,
or comparison where all comparisons true mean const_true_rtx
whole result, or where any comparisons true mean const_true_rtx
whole result. For const0_rtx all the cases are the same. */
if (VECTOR_MODE_P (cmp_mode)
&& SCALAR_INT_MODE_P (mode)
&& res == const_true_rtx)
return NULL_RTX;
return res;
}
/* Simplify a logical operation CODE with result mode MODE, operating on OP0
and OP1, which should be both relational operations. Return 0 if no such
@ -2329,7 +2376,7 @@ simplify_context::simplify_logical_relational_operation (rtx_code code,
int mask = mask0 | mask1;
if (mask == 15)
return const_true_rtx;
return relational_result (mode, GET_MODE (op0), const_true_rtx);
code = mask_to_comparison (mask);
@ -5315,51 +5362,7 @@ simplify_context::simplify_relational_operation (rtx_code code,
tem = simplify_const_relational_operation (code, cmp_mode, op0, op1);
if (tem)
{
if (SCALAR_FLOAT_MODE_P (mode))
{
if (tem == const0_rtx)
return CONST0_RTX (mode);
#ifdef FLOAT_STORE_FLAG_VALUE
{
REAL_VALUE_TYPE val;
val = FLOAT_STORE_FLAG_VALUE (mode);
return const_double_from_real_value (val, mode);
}
#else
return NULL_RTX;
#endif
}
if (VECTOR_MODE_P (mode))
{
if (tem == const0_rtx)
return CONST0_RTX (mode);
#ifdef VECTOR_STORE_FLAG_VALUE
{
rtx val = VECTOR_STORE_FLAG_VALUE (mode);
if (val == NULL_RTX)
return NULL_RTX;
if (val == const1_rtx)
return CONST1_RTX (mode);
return gen_const_vec_duplicate (mode, val);
}
#else
return NULL_RTX;
#endif
}
/* For vector comparison with scalar int result, it is unknown
if the target means here a comparison into an integral bitmask,
or comparison where all comparisons true mean const_true_rtx
whole result, or where any comparisons true mean const_true_rtx
whole result. For const0_rtx all the cases are the same. */
if (VECTOR_MODE_P (cmp_mode)
&& SCALAR_INT_MODE_P (mode)
&& tem == const_true_rtx)
return NULL_RTX;
return tem;
}
return relational_result (mode, cmp_mode, tem);
/* For the following tests, ensure const0_rtx is op1. */
if (swap_commutative_operands_p (op0, op1)

View file

@ -0,0 +1,18 @@
/* PR rtl-optimization/101008 */
/* { dg-do compile } */
/* { dg-options "-O2 -g" } */
typedef unsigned __attribute__((__vector_size__(32))) U;
typedef unsigned __attribute__((__vector_size__(16))) V;
int c, r;
V v;
void
foo(void)
{
U u = __builtin_shufflevector (v, (V)(v != c) | (V)(c == v),
4, 3, 5, 5, 1, 2, 3, 0);
r = ((union { U a; int b; }) u).b;
}