On August 22, 2016 7:17:25 PM GMT+02:00, Joseph Myers <jos...@codesourcery.com>
wrote:
>The __builtin_isinf_sign folding uses a type-specific signbit built-in
>function, meaning it only works for the types float, double and long
>double, not for types such as _FloatN, _FloatNx, __float128. Since
>the signbit built-in function is now type-generic, that can be used
>unconditionally, much as the code uses the type-generic isinf built-in
>function unconditionally, and this patch makes it do so, thereby
>enabling __builtin_isinf_sign (which glibc uses to expand the isinf
>macro since that macro in glibc traditionally provided the stronger
>guarantees about the return value given by __builtin_isinf_sign) to
>work for all floating-point types.
>
>The test gcc.dg/torture/builtin-isinf_sign-1.c needs updating because
>it tests that comparisons of calls to __builtin_isinf_sign to
>conditional expressions involving __builtin_isinf and
>__builtin_signbit* get optimized away, and with a change of what
>particular built-in function for signbit is used, GCC doesn't notice
>the expressions with type-generic and non-type-generic built-in
>functions are equivalent at -O0 or -O1 (it does optimize away the
>original test at -O2).
>
>Bootstrapped with no regressions on x86_64-pc-linux-gnu. OK to
>commit?
OK.
Richard.
>gcc:
>2016-08-22 Joseph Myers <jos...@codesourcery.com>
>
> PR middle-end/77269
> * builtins.c (fold_builtin_classify): Use builtin_decl_explicit
> (BUILT_IN_SIGNBIT) to expand __builtin_isinf_sign.
>
>gcc/testsuite:
>2016-08-22 Joseph Myers <jos...@codesourcery.com>
>
> PR middle-end/77269
> * gcc.dg/torture/builtin-isinf_sign-1.c: Use __builtin_signbit not
> __builtin_signbitf and __builtin_signbitl in expected generic
> expansion.
> * gcc.dg/torture/float128-tg-2.c, gcc.dg/torture/float128x-tg-2.c,
> gcc.dg/torture/float16-tg-2.c, gcc.dg/torture/float32-tg-2.c,
> gcc.dg/torture/float32x-tg-2.c, gcc.dg/torture/float64-tg-2.c,
> gcc.dg/torture/float64x-tg-2.c, gcc.dg/torture/floatn-tg-2.h: New
> tests.
>
>Index: gcc/builtins.c
>===================================================================
>--- gcc/builtins.c (revision 239658)
>+++ gcc/builtins.c (working copy)
>@@ -7881,8 +7881,7 @@ fold_builtin_classify (location_t loc, tree
>fndecl
> /* In a boolean context, GCC will fold the inner COND_EXPR to
> 1. So e.g. "if (isinf_sign(x))" would be folded to just
> "if (isinf(x) ? 1 : 0)" which becomes "if (isinf(x))". */
>- tree signbit_fn = mathfn_built_in_1
>- (TREE_TYPE (arg), CFN_BUILT_IN_SIGNBIT, 0);
>+ tree signbit_fn = builtin_decl_explicit (BUILT_IN_SIGNBIT);
> tree isinf_fn = builtin_decl_explicit (BUILT_IN_ISINF);
> tree tmp = NULL_TREE;
>
>Index: gcc/testsuite/gcc.dg/torture/builtin-isinf_sign-1.c
>===================================================================
>--- gcc/testsuite/gcc.dg/torture/builtin-isinf_sign-1.c (revision
>239658)
>+++ gcc/testsuite/gcc.dg/torture/builtin-isinf_sign-1.c (working copy)
>@@ -15,13 +15,13 @@ foo (float f, double d, long double ld)
> /* Test the generic expansion of isinf_sign. */
>
> if (__builtin_isinf_sign(f)
>- != (__builtin_isinf(f) ? (__builtin_signbitf(f) ? -1 : 1) : 0))
>+ != (__builtin_isinf(f) ? (__builtin_signbit(f) ? -1 : 1) : 0))
> link_error (__LINE__);
> if (__builtin_isinf_sign(d)
> != (__builtin_isinf(d) ? (__builtin_signbit(d) ? -1 : 1) : 0))
> link_error (__LINE__);
> if (__builtin_isinf_sign(ld)
>- != (__builtin_isinf(ld) ? (__builtin_signbitl(ld) ? -1 : 1) :
>0))
>+ != (__builtin_isinf(ld) ? (__builtin_signbit(ld) ? -1 : 1) : 0))
> link_error (__LINE__);
>
> #ifdef __OPTIMIZE__
>Index: gcc/testsuite/gcc.dg/torture/float128-tg-2.c
>===================================================================
>--- gcc/testsuite/gcc.dg/torture/float128-tg-2.c (nonexistent)
>+++ gcc/testsuite/gcc.dg/torture/float128-tg-2.c (working copy)
>@@ -0,0 +1,9 @@
>+/* Test _Float128 type-generic built-in functions:
>__builtin_isinf_sign. */
>+/* { dg-do run } */
>+/* { dg-options "" } */
>+/* { dg-add-options float128 } */
>+/* { dg-require-effective-target float128_runtime } */
>+
>+#define WIDTH 128
>+#define EXT 0
>+#include "floatn-tg-2.h"
>Index: gcc/testsuite/gcc.dg/torture/float128x-tg-2.c
>===================================================================
>--- gcc/testsuite/gcc.dg/torture/float128x-tg-2.c (nonexistent)
>+++ gcc/testsuite/gcc.dg/torture/float128x-tg-2.c (working copy)
>@@ -0,0 +1,9 @@
>+/* Test _Float128x type-generic built-in functions:
>__builtin_isinf_sign. */
>+/* { dg-do run } */
>+/* { dg-options "" } */
>+/* { dg-add-options float128x } */
>+/* { dg-require-effective-target float128x_runtime } */
>+
>+#define WIDTH 128
>+#define EXT 1
>+#include "floatn-tg-2.h"
>Index: gcc/testsuite/gcc.dg/torture/float16-tg-2.c
>===================================================================
>--- gcc/testsuite/gcc.dg/torture/float16-tg-2.c (nonexistent)
>+++ gcc/testsuite/gcc.dg/torture/float16-tg-2.c (working copy)
>@@ -0,0 +1,9 @@
>+/* Test _Float16 type-generic built-in functions:
>__builtin_isinf_sign. */
>+/* { dg-do run } */
>+/* { dg-options "" } */
>+/* { dg-add-options float16 } */
>+/* { dg-require-effective-target float16_runtime } */
>+
>+#define WIDTH 16
>+#define EXT 0
>+#include "floatn-tg-2.h"
>Index: gcc/testsuite/gcc.dg/torture/float32-tg-2.c
>===================================================================
>--- gcc/testsuite/gcc.dg/torture/float32-tg-2.c (nonexistent)
>+++ gcc/testsuite/gcc.dg/torture/float32-tg-2.c (working copy)
>@@ -0,0 +1,9 @@
>+/* Test _Float32 type-generic built-in functions:
>__builtin_isinf_sign. */
>+/* { dg-do run } */
>+/* { dg-options "" } */
>+/* { dg-add-options float32 } */
>+/* { dg-require-effective-target float32_runtime } */
>+
>+#define WIDTH 32
>+#define EXT 0
>+#include "floatn-tg-2.h"
>Index: gcc/testsuite/gcc.dg/torture/float32x-tg-2.c
>===================================================================
>--- gcc/testsuite/gcc.dg/torture/float32x-tg-2.c (nonexistent)
>+++ gcc/testsuite/gcc.dg/torture/float32x-tg-2.c (working copy)
>@@ -0,0 +1,9 @@
>+/* Test _Float32x type-generic built-in functions:
>__builtin_isinf_sign. */
>+/* { dg-do run } */
>+/* { dg-options "" } */
>+/* { dg-add-options float32x } */
>+/* { dg-require-effective-target float32x_runtime } */
>+
>+#define WIDTH 32
>+#define EXT 1
>+#include "floatn-tg-2.h"
>Index: gcc/testsuite/gcc.dg/torture/float64-tg-2.c
>===================================================================
>--- gcc/testsuite/gcc.dg/torture/float64-tg-2.c (nonexistent)
>+++ gcc/testsuite/gcc.dg/torture/float64-tg-2.c (working copy)
>@@ -0,0 +1,9 @@
>+/* Test _Float64 type-generic built-in functions:
>__builtin_isinf_sign. */
>+/* { dg-do run } */
>+/* { dg-options "" } */
>+/* { dg-add-options float64 } */
>+/* { dg-require-effective-target float64_runtime } */
>+
>+#define WIDTH 64
>+#define EXT 0
>+#include "floatn-tg-2.h"
>Index: gcc/testsuite/gcc.dg/torture/float64x-tg-2.c
>===================================================================
>--- gcc/testsuite/gcc.dg/torture/float64x-tg-2.c (nonexistent)
>+++ gcc/testsuite/gcc.dg/torture/float64x-tg-2.c (working copy)
>@@ -0,0 +1,9 @@
>+/* Test _Float64x type-generic built-in functions:
>__builtin_isinf_sign. */
>+/* { dg-do run } */
>+/* { dg-options "" } */
>+/* { dg-add-options float64x } */
>+/* { dg-require-effective-target float64x_runtime } */
>+
>+#define WIDTH 64
>+#define EXT 1
>+#include "floatn-tg-2.h"
>Index: gcc/testsuite/gcc.dg/torture/floatn-tg-2.h
>===================================================================
>--- gcc/testsuite/gcc.dg/torture/floatn-tg-2.h (nonexistent)
>+++ gcc/testsuite/gcc.dg/torture/floatn-tg-2.h (working copy)
>@@ -0,0 +1,54 @@
>+/* Tests for _FloatN / _FloatNx types: compile and execution tests for
>+ type-generic built-in functions: __builtin_isinf_sign. Before
>+ including this file, define WIDTH as the value N; define EXT to 1
>+ for _FloatNx and 0 for _FloatN. */
>+
>+#define __STDC_WANT_IEC_60559_TYPES_EXT__
>+#include <float.h>
>+
>+#define CONCATX(X, Y) X ## Y
>+#define CONCAT(X, Y) CONCATX (X, Y)
>+#define CONCAT3(X, Y, Z) CONCAT (CONCAT (X, Y), Z)
>+#define CONCAT4(W, X, Y, Z) CONCAT (CONCAT (CONCAT (W, X), Y), Z)
>+
>+#if EXT
>+# define TYPE CONCAT3 (_Float, WIDTH, x)
>+# define CST(C) CONCAT4 (C, f, WIDTH, x)
>+# define MAX CONCAT3 (FLT, WIDTH, X_MAX)
>+#else
>+# define TYPE CONCAT (_Float, WIDTH)
>+# define CST(C) CONCAT3 (C, f, WIDTH)
>+# define MAX CONCAT3 (FLT, WIDTH, _MAX)
>+#endif
>+
>+extern void exit (int);
>+extern void abort (void);
>+
>+volatile TYPE inf = __builtin_inf (), nanval = __builtin_nan ("");
>+volatile TYPE neginf = -__builtin_inf (), negnanval = -__builtin_nan
>("");
>+volatile TYPE zero = CST (0.0), negzero = -CST (0.0), one = CST (1.0);
>+volatile TYPE max = MAX, negmax = -MAX;
>+
>+int
>+main (void)
>+{
>+ if (__builtin_isinf_sign (inf) != 1)
>+ abort ();
>+ if (__builtin_isinf_sign (neginf) != -1)
>+ abort ();
>+ if (__builtin_isinf_sign (nanval) != 0)
>+ abort ();
>+ if (__builtin_isinf_sign (negnanval) != 0)
>+ abort ();
>+ if (__builtin_isinf_sign (zero) != 0)
>+ abort ();
>+ if (__builtin_isinf_sign (negzero) != 0)
>+ abort ();
>+ if (__builtin_isinf_sign (one) != 0)
>+ abort ();
>+ if (__builtin_isinf_sign (max) != 0)
>+ abort ();
>+ if (__builtin_isinf_sign (negmax) != 0)
>+ abort ();
>+ exit (0);
>+}
