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authorUros Bizjak <ubizjak@gmail.com>2007-07-03 07:53:58 +0200
committerUros Bizjak <uros@gcc.gnu.org>2007-07-03 07:53:58 +0200
commitc77cd3d140cbf8fa02a5383c3d1f6afabe7a33c3 (patch)
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parent1ed50f7194d46aa97af8072b0da2bcd68f906488 (diff)
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cpplib.h (CPP_N_WIDTH_MD, [...]): Add new constants.
libcpp/ChangeLog: * include/cpplib.h (CPP_N_WIDTH_MD, CPP_N_MD_W, CPP_N_MD_Q): Add new constants. * expr.c (interpret_float_suffix): Process 'w', 'W', 'q' and 'Q' suffixes. Return CPP_N_MD_W for 'w' or 'W' suffixes and CPP_N_MD_Q for 'q' or 'Q' suffixes. gcc/ChangeLog: * targhooks.h (default_mode_for_suffix): New function declaration. * targhooks.c (default_mode_for_suffix): New default target hook. * target.h (struct c): New structure in the targetm struct. (mode_for_suffix): New target hook as part of struct c. target-def.h (TARGET_C_MODE_FOR_SUFFIX): Define as default_mode_for_suffix. (TARGET_C): New define. * c-lex.c: Include "target.h". (interpret_float): Use targetm.c.mode_for_suffix to determine the mode for a given non-standard suffix. Makefile.in (c-lex.o): Depend on $(TARGET_H). * config/i386/i386.c (ix86_c_mode_for_suffix): New static function. (TARGET_C_MODE_FOR_SUFFIX): Define to ix86_c_mode_for_suffix. * doc/extend.texi (Floating Types): New node. Document __float80 and __float128 types. Document 'w', 'W', 'q' and 'Q' suffixes. testsuite/ChangeLog: * gcc.dg/const-float80.c : New test. * gcc.dg/const-float128.c : New test. * gcc.dg/const-float80-ped.c : New test. * gcc.dg/const-float128-ped.c : New test. From-SVN: r126244
Diffstat (limited to 'gcc/doc')
-rw-r--r--gcc/doc/extend.texi32
1 files changed, 32 insertions, 0 deletions
diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
index 76cc546f..0a1cdeb 100644
--- a/gcc/doc/extend.texi
+++ b/gcc/doc/extend.texi
@@ -33,6 +33,7 @@ extensions, accepted by GCC in C89 mode and in C++.
* Conditionals:: Omitting the middle operand of a @samp{?:} expression.
* Long Long:: Double-word integers---@code{long long int}.
* Complex:: Data types for complex numbers.
+* Floating Types:: Additional Floating Types.
* Decimal Float:: Decimal Floating Types.
* Hex Floats:: Hexadecimal floating-point constants.
* Zero Length:: Zero-length arrays.
@@ -816,6 +817,37 @@ If the variable's actual name is @code{foo}, the two fictitious
variables are named @code{foo$real} and @code{foo$imag}. You can
examine and set these two fictitious variables with your debugger.
+@node Floating Types
+@section Additional Floating Types
+@cindex additional floating types
+@cindex @code{__float80} data type
+@cindex @code{__float128} data type
+@cindex @code{w} floating point suffix
+@cindex @code{q} floating point suffix
+@cindex @code{W} floating point suffix
+@cindex @code{Q} floating point suffix
+
+As an extension, the GNU C compiler supports additional floating
+types, @code{__float80} and @code{__float128} to support 80bit
+(@code{XFmode}) and 128 bit (@code{TFmode}) floating types.
+Support for additional types includes the arithmetic operators:
+add, subtract, multiply, divide; unary arithmetic operators;
+relational operators; equality operators; and conversions to and from
+integer and other floating types. Use a suffix @samp{w} or @samp{W}
+in a literal constant of type @code{__float80} and @samp{q} or @samp{Q}
+for @code{_float128}. You can declare complex types using the
+corresponding internal complex type, @code{XCmode} for @code{__float80}
+type and @code{TCmode} for @code{__float128} type:
+
+@smallexample
+typedef _Complex float __attribute__((mode(TC))) _Complex128;
+typedef _Complex float __attribute__((mode(XC))) _Complex80;
+@end smallexample
+
+Not all targets support additional floating point types. @code{__float80}
+is supported on i386, x86_64 and ia64 targets and target @code{__float128}
+is supported on x86_64 and ia64 targets.
+
@node Decimal Float
@section Decimal Floating Types
@cindex decimal floating types