[RS6000] CONST_DOUBLE tidy
Alan Modra
amodra@gmail.com
Sun Nov 25 12:16:00 GMT 2018
Once upon a time CONST_DOUBLE was used to hold large integer constants
that didn't fit into a CONST_INT. Now that CONST_INT is always at
least 64 bits, and the rs6000 backend uses CONST_WIDE_INT for larger
integers, there is no need for old code dealing with integers in
CONST_DOUBLE. The rs6000 backend also doesn't create DImode subregs
of TFmode CONST_DOUBLE, as once we did. This patch cleans up a few
leftovers from the past.
Bootstrapped etc. powerpc64le-linux, and powerpc64-linux testing
both -m32 and -m64.
* config/rs6000/predicates.md (easy_fp_constant): Remove code
dealing with integers in const_double. Assert on unexpected
modes.
* config/rs6000/rs6000.c (rs6000_emit_move): Comment fixes.
Don't call easy_fp_constant for Pmode.
(rs6000_hash_constant): Remove code dealing with integers in
const_double.
(rs6000_legitimate_constant_p): Likewise.
(output_toc): Formatting, use CONST_DOUBLE_P.
diff --git a/gcc/config/rs6000/predicates.md b/gcc/config/rs6000/predicates.md
index afe1b286833..9fbeb928fe6 100644
--- a/gcc/config/rs6000/predicates.md
+++ b/gcc/config/rs6000/predicates.md
@@ -562,12 +562,11 @@ (define_predicate "vsx_reg_or_cint_operand"
(define_predicate "easy_fp_constant"
(match_code "const_double")
{
- if (GET_MODE (op) != mode
- || (!SCALAR_FLOAT_MODE_P (mode) && mode != DImode))
- return 0;
+ gcc_assert (GET_MODE (op) == mode
+ && SCALAR_FLOAT_MODE_P (mode));
/* Consider all constants with -msoft-float to be easy. */
- if (TARGET_SOFT_FLOAT && mode != DImode)
+ if (TARGET_SOFT_FLOAT)
return 1;
/* 0.0D is not all zero bits. */
@@ -575,37 +574,15 @@ (define_predicate "easy_fp_constant"
return 0;
/* The constant 0.0 is easy under VSX. */
- if (TARGET_VSX && SCALAR_FLOAT_MODE_P (mode) && op == CONST0_RTX (mode))
+ if (TARGET_VSX && op == CONST0_RTX (mode))
return 1;
- /* If we are using V.4 style PIC, consider all constants to be hard. */
- if (flag_pic && DEFAULT_ABI == ABI_V4)
- return 0;
-
- /* If we have real FPRs, consider floating point constants hard (other than
- 0.0 under VSX), so that the constant gets pushed to memory during the
- early RTL phases. This has the advantage that double precision constants
- that can be represented in single precision without a loss of precision
- will use single precision loads. */
-
- switch (mode)
- {
- case E_KFmode:
- case E_IFmode:
- case E_TFmode:
- case E_DFmode:
- case E_SFmode:
- return 0;
-
- case E_DImode:
- return (num_insns_constant (op, DImode) <= 2);
-
- case E_SImode:
- return 1;
-
- default:
- gcc_unreachable ();
- }
+ /* Otherwise consider floating point constants hard, so that the
+ constant gets pushed to memory during the early RTL phases. This
+ has the advantage that double precision constants that can be
+ represented in single precision without a loss of precision will
+ use single precision loads. */
+ return 0;
})
;; Return 1 if the operand is a constant that can loaded with a XXSPLTIB
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 479dae547fa..42dcb61904c 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -9883,13 +9883,10 @@ rs6000_emit_move (rtx dest, rtx source, machine_mode mode)
debug_rtx (source);
}
- /* Sanity checks. Check that we get CONST_DOUBLE only when we should. */
+ /* Check that we get CONST_WIDE_INT only when we should. */
if (CONST_WIDE_INT_P (operands[1])
&& GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_WIDE_INT)
- {
- /* This should be fixed with the introduction of CONST_WIDE_INT. */
- gcc_unreachable ();
- }
+ gcc_unreachable ();
#ifdef HAVE_AS_GNU_ATTRIBUTE
/* If we use a long double type, set the flags in .gnu_attribute that say
@@ -10228,13 +10225,11 @@ rs6000_emit_move (rtx dest, rtx source, machine_mode mode)
else if (mode == Pmode
&& CONSTANT_P (operands[1])
&& GET_CODE (operands[1]) != HIGH
- && ((GET_CODE (operands[1]) != CONST_INT
- && ! easy_fp_constant (operands[1], mode))
- || (GET_CODE (operands[1]) == CONST_INT
- && (num_insns_constant (operands[1], mode)
- > (TARGET_CMODEL != CMODEL_SMALL ? 3 : 2)))
- || (GET_CODE (operands[0]) == REG
- && FP_REGNO_P (REGNO (operands[0]))))
+ && ((REG_P (operands[0])
+ && FP_REGNO_P (REGNO (operands[0])))
+ || !CONST_INT_P (operands[1])
+ || (num_insns_constant (operands[1], mode)
+ > (TARGET_CMODEL != CMODEL_SMALL ? 3 : 2)))
&& !toc_relative_expr_p (operands[1], false, NULL, NULL)
&& (TARGET_CMODEL == CMODEL_SMALL
|| can_create_pseudo_p ()
@@ -29430,10 +29425,7 @@ rs6000_hash_constant (rtx k)
}
case CONST_DOUBLE:
- if (mode != VOIDmode)
- return real_hash (CONST_DOUBLE_REAL_VALUE (k)) * result;
- flen = 2;
- break;
+ return real_hash (CONST_DOUBLE_REAL_VALUE (k)) * result;
case CODE_LABEL:
fidx = 3;
@@ -29638,9 +29630,9 @@ output_toc (FILE *file, rtx x, int labelno, machine_mode mode)
/* Handle FP constants specially. Note that if we have a minimal
TOC, things we put here aren't actually in the TOC, so we can allow
FP constants. */
- if (GET_CODE (x) == CONST_DOUBLE &&
- (GET_MODE (x) == TFmode || GET_MODE (x) == TDmode
- || GET_MODE (x) == IFmode || GET_MODE (x) == KFmode))
+ if (CONST_DOUBLE_P (x)
+ && (GET_MODE (x) == TFmode || GET_MODE (x) == TDmode
+ || GET_MODE (x) == IFmode || GET_MODE (x) == KFmode))
{
long k[4];
@@ -29678,8 +29670,8 @@ output_toc (FILE *file, rtx x, int labelno, machine_mode mode)
return;
}
}
- else if (GET_CODE (x) == CONST_DOUBLE &&
- (GET_MODE (x) == DFmode || GET_MODE (x) == DDmode))
+ else if (CONST_DOUBLE_P (x)
+ && (GET_MODE (x) == DFmode || GET_MODE (x) == DDmode))
{
long k[2];
@@ -29712,8 +29704,8 @@ output_toc (FILE *file, rtx x, int labelno, machine_mode mode)
return;
}
}
- else if (GET_CODE (x) == CONST_DOUBLE &&
- (GET_MODE (x) == SFmode || GET_MODE (x) == SDmode))
+ else if (CONST_DOUBLE_P (x)
+ && (GET_MODE (x) == SFmode || GET_MODE (x) == SDmode))
{
long l;
@@ -37615,11 +37607,13 @@ rs6000_legitimate_constant_p (machine_mode mode, rtx x)
if (TARGET_ELF && tls_referenced_p (x))
return false;
- return ((GET_CODE (x) != CONST_DOUBLE && GET_CODE (x) != CONST_VECTOR)
- || GET_MODE (x) == VOIDmode
- || (TARGET_POWERPC64 && mode == DImode)
- || easy_fp_constant (x, mode)
- || easy_vector_constant (x, mode));
+ if (CONST_DOUBLE_P (x))
+ return easy_fp_constant (x, mode);
+
+ if (GET_CODE (x) == CONST_VECTOR)
+ return easy_vector_constant (x, mode);
+
+ return true;
}
--
Alan Modra
Australia Development Lab, IBM
More information about the Gcc-patches
mailing list