My understanding is that GCC's preferred null value for rtx is NULL_RTX
(and for tree is NULL_TREE), and by being typed allows strict type checking,
and use with function polymorphism and template instantiation.
C++'s nullptr is preferred over NULL and 0 for pointer types that don't
have a defined null of the correct type.
This minor clean-up uses NULL_RTX consistently in i386-expand.cc.
This patch has been tested on x86_64-pc-linux-gnu with make bootstrap
and make -k check, both with and without --target_board=unix{-m32}
with no new failures. Ok for mainline? Is my understanding correct?
2023-05-24 Roger Sayle <ro...@nextmovesoftware.com>
gcc/ChangeLog
* config/i386/i386.cc (ix86_convert_wide_int_to_broadcast): Use
NULL_RTX instead of nullptr.
(ix86_convert_const_wide_int_to_broadcast): Likewise.
(ix86_broadcast_from_constant): Likewise.
(ix86_expand_vector_move): Likewise.
(ix86_extract_perm_from_pool_constant): Likewise.
Thanks,
Roger
--
diff --git a/gcc/config/i386/i386-expand.cc b/gcc/config/i386/i386-expand.cc
index 634fe61..a867288 100644
--- a/gcc/config/i386/i386-expand.cc
+++ b/gcc/config/i386/i386-expand.cc
@@ -296,7 +296,7 @@ ix86_convert_const_wide_int_to_broadcast (machine_mode
mode, rtx op)
/* Don't use integer vector broadcast if we can't move from GPR to SSE
register directly. */
if (!TARGET_INTER_UNIT_MOVES_TO_VEC)
- return nullptr;
+ return NULL_RTX;
/* Convert CONST_WIDE_INT to a non-standard SSE constant integer
broadcast only if vector broadcast is available. */
@@ -305,7 +305,7 @@ ix86_convert_const_wide_int_to_broadcast (machine_mode
mode, rtx op)
|| standard_sse_constant_p (op, mode)
|| (CONST_WIDE_INT_NUNITS (op) * HOST_BITS_PER_WIDE_INT
!= GET_MODE_BITSIZE (mode)))
- return nullptr;
+ return NULL_RTX;
HOST_WIDE_INT val = CONST_WIDE_INT_ELT (op, 0);
HOST_WIDE_INT val_broadcast;
@@ -326,12 +326,12 @@ ix86_convert_const_wide_int_to_broadcast (machine_mode
mode, rtx op)
val_broadcast))
broadcast_mode = DImode;
else
- return nullptr;
+ return NULL_RTX;
/* Check if OP can be broadcasted from VAL. */
for (int i = 1; i < CONST_WIDE_INT_NUNITS (op); i++)
if (val != CONST_WIDE_INT_ELT (op, i))
- return nullptr;
+ return NULL_RTX;
unsigned int nunits = (GET_MODE_SIZE (mode)
/ GET_MODE_SIZE (broadcast_mode));
@@ -525,7 +525,7 @@ ix86_expand_move (machine_mode mode, rtx operands[])
{
rtx tmp = ix86_convert_const_wide_int_to_broadcast
(GET_MODE (op0), op1);
- if (tmp != nullptr)
+ if (tmp != NULL_RTX)
op1 = tmp;
}
}
@@ -541,13 +541,13 @@ ix86_broadcast_from_constant (machine_mode mode, rtx op)
{
int nunits = GET_MODE_NUNITS (mode);
if (nunits < 2)
- return nullptr;
+ return NULL_RTX;
/* Don't use integer vector broadcast if we can't move from GPR to SSE
register directly. */
if (!TARGET_INTER_UNIT_MOVES_TO_VEC
&& INTEGRAL_MODE_P (mode))
- return nullptr;
+ return NULL_RTX;
/* Convert CONST_VECTOR to a non-standard SSE constant integer
broadcast only if vector broadcast is available. */
@@ -557,7 +557,7 @@ ix86_broadcast_from_constant (machine_mode mode, rtx op)
|| GET_MODE_INNER (mode) == DImode))
|| FLOAT_MODE_P (mode))
|| standard_sse_constant_p (op, mode))
- return nullptr;
+ return NULL_RTX;
/* Don't broadcast from a 64-bit integer constant in 32-bit mode.
We can still put 64-bit integer constant in memory when
@@ -565,14 +565,14 @@ ix86_broadcast_from_constant (machine_mode mode, rtx op)
if (GET_MODE_INNER (mode) == DImode && !TARGET_64BIT
&& (!TARGET_AVX512F
|| (GET_MODE_SIZE (mode) < 64 && !TARGET_AVX512VL)))
- return nullptr;
+ return NULL_RTX;
if (GET_MODE_INNER (mode) == TImode)
- return nullptr;
+ return NULL_RTX;
rtx constant = get_pool_constant (XEXP (op, 0));
if (GET_CODE (constant) != CONST_VECTOR)
- return nullptr;
+ return NULL_RTX;
/* There could be some rtx like
(mem/u/c:V16QI (symbol_ref/u:DI ("*.LC1")))
@@ -581,8 +581,8 @@ ix86_broadcast_from_constant (machine_mode mode, rtx op)
{
constant = simplify_subreg (mode, constant, GET_MODE (constant),
0);
- if (constant == nullptr || GET_CODE (constant) != CONST_VECTOR)
- return nullptr;
+ if (constant == NULL_RTX || GET_CODE (constant) != CONST_VECTOR)
+ return NULL_RTX;
}
rtx first = XVECEXP (constant, 0, 0);
@@ -592,7 +592,7 @@ ix86_broadcast_from_constant (machine_mode mode, rtx op)
rtx tmp = XVECEXP (constant, 0, i);
/* Vector duplicate value. */
if (!rtx_equal_p (tmp, first))
- return nullptr;
+ return NULL_RTX;
}
return first;
@@ -641,7 +641,7 @@ ix86_expand_vector_move (machine_mode mode, rtx operands[])
machine_mode mode = GET_MODE (op0);
rtx tmp = ix86_convert_const_wide_int_to_broadcast
(mode, op1);
- if (tmp == nullptr)
+ if (tmp == NULL_RTX)
op1 = validize_mem (force_const_mem (mode, op1));
else
op1 = tmp;
@@ -656,7 +656,7 @@ ix86_expand_vector_move (machine_mode mode, rtx operands[])
&& CONSTANT_POOL_ADDRESS_P (XEXP (op1, 0))))
{
rtx first = ix86_broadcast_from_constant (mode, op1);
- if (first != nullptr)
+ if (first != NULL_RTX)
{
/* Broadcast to XMM/YMM/ZMM register from an integer
constant or scalar mem. */
@@ -5797,7 +5797,7 @@ ix86_extract_perm_from_pool_constant (int* perm, rtx mem)
{
constant = simplify_subreg (mode, constant, GET_MODE (constant), 0);
- if (constant == nullptr || GET_CODE (constant) != CONST_VECTOR)
+ if (constant == NULL_RTX || GET_CODE (constant) != CONST_VECTOR)
return false;
}
