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riscv-gcc-1
Commit b4838d77 by Richard Sandiford Committed by Richard Sandiford
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Move pow folds to match.pd 

Tested on x86_64-linux-gnu, aarch64-linux-gnu and arm-linux-gnueabi.

gcc/
	* builtins.c (fold_builtin_pow): Delete in favor of...
	(fold_const_builtin_pow): ...this new function.  Only handle constant
	arguments.
	(fold_builtin_2): Update accordingly.
	* match.pd: Add rules previously handled by fold_builtin_pow.

gcc/testsuite/
	* gcc.dg/torture/builtin-math-1.c: Skip at -O0.

From-SVN: r229408
parent 4d7836c4
Showing with 88 additions and 123 deletions
gcc/ChangeLog
2015-10-27 Richard Sandiford <richard.sandiford@arm.com>
* builtins.c (fold_builtin_pow): Delete in favor of...
(fold_const_builtin_pow): ...this new function. Only handle constant
arguments.
(fold_builtin_2): Update accordingly.
* match.pd: Add rules previously handled by fold_builtin_pow.
2015-10-27 Richard Sandiford <richard.sandiford@arm.com>
* builtins.c (fold_builtin_hypot): Delete.
(fold_builtin_2): Handle constant hypot arguments here.
* match.pd: Fold hypot(x, 0) and hypot(0, x) to x. Canonicalize
gcc/builtins.c
......@@ -156,7 +156,6 @@ static tree rewrite_call_expr (location_t, tree, int, tree, int, ...);
static bool validate_arg (const_tree, enum tree_code code);
static rtx expand_builtin_fabs (tree, rtx, rtx);
static rtx expand_builtin_signbit (tree, rtx);
static tree fold_builtin_pow (location_t, tree, tree, tree, tree);
static tree fold_builtin_powi (location_t, tree, tree, tree, tree);
static tree fold_builtin_bitop (tree, tree);
static tree fold_builtin_strchr (location_t, tree, tree, tree);
......@@ -7478,7 +7477,7 @@ fold_builtin_bswap (tree fndecl, tree arg)
/* Fold a builtin function call to pow, powf, or powl. Return
NULL_TREE if no simplification can be made. */
static tree
fold_builtin_pow (location_t loc, tree fndecl, tree arg0, tree arg1, tree type)
fold_const_builtin_pow (tree arg0, tree arg1, tree type)
{
tree res;
......@@ -7490,127 +7489,28 @@ fold_builtin_pow (location_t loc, tree fndecl, tree arg0, tree arg1, tree type)
if ((res = do_mpfr_arg2 (arg0, arg1, type, mpfr_pow)))
return res;
/* Optimize pow(1.0,y) = 1.0. */
if (real_onep (arg0))
return omit_one_operand_loc (loc, type, build_real (type, dconst1), arg1);
if (TREE_CODE (arg1) == REAL_CST
/* Check for an integer exponent. */
if (TREE_CODE (arg0) == REAL_CST
&& !TREE_OVERFLOW (arg0)
&& TREE_CODE (arg1) == REAL_CST
&& !TREE_OVERFLOW (arg1))
{
REAL_VALUE_TYPE cint;
REAL_VALUE_TYPE c;
HOST_WIDE_INT n;
c = TREE_REAL_CST (arg1);
/* Optimize pow(x,0.0) = 1.0. */
if (real_equal (&c, &dconst0))
return omit_one_operand_loc (loc, type, build_real (type, dconst1),
arg0);
/* Optimize pow(x,1.0) = x. */
if (real_equal (&c, &dconst1))
return arg0;
/* Optimize pow(x,-1.0) = 1.0/x. */
if (real_equal (&c, &dconstm1))
return fold_build2_loc (loc, RDIV_EXPR, type,
build_real (type, dconst1), arg0);
/* Optimize pow(x,0.5) = sqrt(x). */
if (flag_unsafe_math_optimizations
&& real_equal (&c, &dconsthalf))
REAL_VALUE_TYPE cint1;
const REAL_VALUE_TYPE *c0 = TREE_REAL_CST_PTR (arg0);
const REAL_VALUE_TYPE *c1 = TREE_REAL_CST_PTR (arg1);
HOST_WIDE_INT n1 = real_to_integer (c1);
real_from_integer (&cint1, VOIDmode, n1, SIGNED);
/* Attempt to evaluate pow at compile-time, unless this should
raise an exception. */
if (real_identical (c1, &cint1)
&& (n1 > 0
|| (!flag_trapping_math && !flag_errno_math)
|| !real_equal (c0, &dconst0)))
{
tree sqrtfn = mathfn_built_in (type, BUILT_IN_SQRT);
if (sqrtfn != NULL_TREE)
return build_call_expr_loc (loc, sqrtfn, 1, arg0);
}
/* Optimize pow(x,1.0/3.0) = cbrt(x). */
if (flag_unsafe_math_optimizations)
{
const REAL_VALUE_TYPE dconstroot
= real_value_truncate (TYPE_MODE (type), dconst_third ());
if (real_equal (&c, &dconstroot))
{
tree cbrtfn = mathfn_built_in (type, BUILT_IN_CBRT);
if (cbrtfn != NULL_TREE)
return build_call_expr_loc (loc, cbrtfn, 1, arg0);
}
}
/* Check for an integer exponent. */
n = real_to_integer (&c);
real_from_integer (&cint, VOIDmode, n, SIGNED);
if (real_identical (&c, &cint))
{
/* Attempt to evaluate pow at compile-time, unless this should
raise an exception. */
if (TREE_CODE (arg0) == REAL_CST
&& !TREE_OVERFLOW (arg0)
&& (n > 0
|| (!flag_trapping_math && !flag_errno_math)
|| !real_equal (&TREE_REAL_CST (arg0), &dconst0)))
{
REAL_VALUE_TYPE x;
bool inexact;
x = TREE_REAL_CST (arg0);
inexact = real_powi (&x, TYPE_MODE (type), &x, n);
if (flag_unsafe_math_optimizations || !inexact)
return build_real (type, x);
}
}
}
if (flag_unsafe_math_optimizations)
{
const enum built_in_function fcode = builtin_mathfn_code (arg0);
/* Optimize pow(expN(x),y) = expN(x*y). */
if (BUILTIN_EXPONENT_P (fcode))
{
tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
tree arg = CALL_EXPR_ARG (arg0, 0);
arg = fold_build2_loc (loc, MULT_EXPR, type, arg, arg1);
return build_call_expr_loc (loc, expfn, 1, arg);
}
/* Optimize pow(sqrt(x),y) = pow(x,y*0.5). */
if (BUILTIN_SQRT_P (fcode))
{
tree narg0 = CALL_EXPR_ARG (arg0, 0);
tree narg1 = fold_build2_loc (loc, MULT_EXPR, type, arg1,
build_real (type, dconsthalf));
return build_call_expr_loc (loc, fndecl, 2, narg0, narg1);
}
/* Optimize pow(cbrt(x),y) = pow(x,y/3) iff x is nonnegative. */
if (BUILTIN_CBRT_P (fcode))
{
tree arg = CALL_EXPR_ARG (arg0, 0);
if (tree_expr_nonnegative_p (arg))
{
tree c = build_real_truncate (type, dconst_third ());
tree narg1 = fold_build2_loc (loc, MULT_EXPR, type, arg1, c);
return build_call_expr_loc (loc, fndecl, 2, arg, narg1);
}
}
/* Optimize pow(pow(x,y),z) = pow(x,y*z) iff x is nonnegative. */
if (fcode == BUILT_IN_POW
|| fcode == BUILT_IN_POWF
|| fcode == BUILT_IN_POWL)
{
tree arg00 = CALL_EXPR_ARG (arg0, 0);
if (tree_expr_nonnegative_p (arg00))
{
tree arg01 = CALL_EXPR_ARG (arg0, 1);
tree narg1 = fold_build2_loc (loc, MULT_EXPR, type, arg01, arg1);
return build_call_expr_loc (loc, fndecl, 2, arg00, narg1);
}
REAL_VALUE_TYPE x;
bool inexact = real_powi (&x, TYPE_MODE (type), c0, n1);
if (flag_unsafe_math_optimizations || !inexact)
return build_real (type, x);
}
}
......@@ -9476,7 +9376,7 @@ fold_builtin_2 (location_t loc, tree fndecl, tree arg0, tree arg1)
return fold_builtin_expect (loc, arg0, arg1, NULL_TREE);
CASE_FLT_FN (BUILT_IN_POW):
return fold_builtin_pow (loc, fndecl, arg0, arg1, type);
return fold_const_builtin_pow (arg0, arg1, type);
CASE_FLT_FN (BUILT_IN_POWI):
return fold_builtin_powi (loc, fndecl, arg0, arg1, type);
......
gcc/match.pd
......@@ -2480,6 +2480,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
(for sqrts (SQRT)
cbrts (CBRT)
pows (POW)
exps (EXP EXP2 EXP10 POW10)
/* sqrt(expN(x)) -> expN(x*0.5). */
(simplify
......@@ -2488,7 +2489,11 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
/* cbrt(expN(x)) -> expN(x/3). */
(simplify
(cbrts (exps @0))
(exps (mult @0 { build_real_truncate (type, dconst_third ()); }))))
(exps (mult @0 { build_real_truncate (type, dconst_third ()); })))
/* pow(expN(x), y) -> expN(x*y). */
(simplify
(pows (exps @0) @1)
(exps (mult @0 @1))))
/* tan(atan(x)) -> x. */
(for tans (TAN)
......@@ -2524,6 +2529,11 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
(hypot:c @0 real_zerop@1)
(abs @0))
/* pow(1,x) -> 1. */
(simplify
(POW real_onep@0 @1)
@0)
/* Canonicalization of sequences of math builtins. These rules represent
IL simplifications but are not necessarily optimizations.
......@@ -2615,7 +2625,19 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
/* cbrt(pow(x,y)) -> pow(x,y/3), iff x is nonnegative. */
(simplify
(cbrts (pows tree_expr_nonnegative_p@0 @1))
(pows @0 (mult @1 { build_real_truncate (type, dconst_third ()); }))))
(pows @0 (mult @1 { build_real_truncate (type, dconst_third ()); })))
/* pow(sqrt(x),y) -> pow(x,y*0.5). */
(simplify
(pows (sqrts @0) @1)
(pows @0 (mult @1 { build_real (type, dconsthalf); })))
/* pow(cbrt(x),y) -> pow(x,y/3) iff x is nonnegative. */
(simplify
(pows (cbrts tree_expr_nonnegative_p@0) @1)
(pows @0 (mult @1 { build_real_truncate (type, dconst_third ()); })))
/* pow(pow(x,y),z) -> pow(x,y*z) iff x is nonnegative. */
(simplify
(pows (pows tree_expr_nonnegative_p@0 @1) @2)
(pows @0 (mult @1 @2))))
/* cabs(x+xi) -> fabs(x)*sqrt(2). */
(simplify
......@@ -2767,6 +2789,36 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
(if (real_isinf (TREE_REAL_CST_PTR (@1)))
{ build_complex_inf (type, TREE_REAL_CST_PTR (@1)->sign); }))
(for pows (POW)
sqrts (SQRT)
cbrts (CBRT)
(simplify
(pows @0 REAL_CST@1)
(with {
const REAL_VALUE_TYPE *value = TREE_REAL_CST_PTR (@1);
REAL_VALUE_TYPE tmp;
}
(switch
/* pow(x,0) -> 1. */
(if (real_equal (value, &dconst0))
{ build_real (type, dconst1); })
/* pow(x,1) -> x. */
(if (real_equal (value, &dconst1))
@0)
/* pow(x,-1) -> 1/x. */
(if (real_equal (value, &dconstm1))
(rdiv { build_real (type, dconst1); } @0))
/* pow(x,0.5) -> sqrt(x). */
(if (flag_unsafe_math_optimizations
&& canonicalize_math_p ()
&& real_equal (value, &dconsthalf))
(sqrts @0))
/* pow(x,1/3) -> cbrt(x). */
(if (flag_unsafe_math_optimizations
&& canonicalize_math_p ()
&& (tmp = real_value_truncate (TYPE_MODE (type), dconst_third ()),
real_equal (value, &tmp)))
(cbrts @0))))))
/* Narrowing of arithmetic and logical operations.
......
gcc/testsuite/ChangeLog
2015-10-27 Richard Sandiford <richard.sandiford@arm.com>
* gcc.dg/torture/builtin-math-1.c: Skip at -O0.
2015-10-27 Thomas Schwinge <thomas@codesourcery.com>
PR c/64765
......
gcc/testsuite/gcc.dg/torture/builtin-math-1.c
......@@ -6,6 +6,7 @@
Written by Roger Sayle, 16th August 2002. */
/* { dg-do link } */
/* { dg-skip-if "" { *-*-* } { "-O0" } { "" } } */
extern double atan (double);
extern float atanf (float);
......
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