linux.h (GLIBC_DYNAMIC_LINKER): Handle `-mnan=2008'.

	gcc/
	* config/mips/linux.h (GLIBC_DYNAMIC_LINKER): Handle `-mnan=2008'.
	(UCLIBC_DYNAMIC_LINKER): New macro.
	* config/mips/linux64.h (GLIBC_DYNAMIC_LINKER32): Handle
	`-mnan=2008'.
	(GLIBC_DYNAMIC_LINKER64, GLIBC_DYNAMIC_LINKERN32): Likewise.
	(UCLIBC_DYNAMIC_LINKER32): Undefine macro first.  Handle
	`-mnan=2008'.
	(UCLIBC_DYNAMIC_LINKER64): Redefine macro.
	(UCLIBC_DYNAMIC_LINKERN32): Likewise.
	* config/mips/mips-modes.def: Remove RESET_FLOAT_FORMAT calls
	for SF and DF modes.  Use ieee_quad_format for TF mode.
	* config/mips/mips-opts.h (mips_ieee_754_setting): New enum.
	* config/mips/mips.c (mips_file_start): Output a `.nan' directive.
	(mips_option_override): Handle `-mnan=legacy'.
	* config/mips/mips.h (TARGET_CPU_CPP_BUILTINS): Handle
	`-mabs=2008' and `-mnan=2008'.
	(OPTION_DEFAULT_SPECS): Add "nan" default.
	(ASM_SPEC): Handle `-mnan='.
	[!HAVE_AS_NAN] (HAVE_AS_NAN): New macro.
	* config/mips/mips.md (abs<mode>2): Handle `-mabs=2008', update
	comment accordingly.
	(neg<mode>2): Likewise.
	* config/mips/mips.opt (mabs, mnan): New options.
	* doc/install.texi (Configuration): Document `--with-nan=' option.
	* doc/invoke.texi (Option Summary): List MIPS `-mabs=' and
	`-mnan=' options.
	(MIPS Options): Document them.
	* config.gcc <mips*-*-*>: Handle `--with-nan='.
	* configure.ac <mips*-*-*>: Check for GAS `-mnan=2008' support.
	* configure: Regenerate.
	* config.in: Regenerate.

	gcc/testsuite/
	* gcc.target/mips/fabs-2008.c: New test case.
	* gcc.target/mips/fabs-legacy.c: New test case.
	* gcc.target/mips/fabsf-2008.c: New test case.
	* gcc.target/mips/fabsf-legacy.c: New test case.
	* gcc.target/mips/fneg-2008.c: New test case.
	* gcc.target/mips/fneg-legacy.c: New test case.
	* gcc.target/mips/fneg-2008.c: New test case.
	* gcc.target/mips/fneg-legacy.c: New test case.
	* gcc.target/mips/nan-2008.c: New test case.
	* gcc.target/mips/nan-legacy.c: New test case.
	* gcc.target/mips/nanf-2008.c: New test case.
	* gcc.target/mips/nanf-legacy.c: New test case.
	* gcc.target/mips/nans-2008.c: New test case.
	* gcc.target/mips/nans-legacy.c: New test case.
	* gcc.target/mips/nansf-2008.c: New test case.
	* gcc.target/mips/nansf-legacy.c: New test case.
	* gcc.target/mips/mips.exp: Handle `-mabs=' and `-mnan='.

From-SVN: r201313

2 files changed, 62 insertions, 1 deletions

diff --git a/gcc/doc/install.texi b/gcc/doc/install.texi
index e05cbed..9e5ba5e 100644
--- a/gcc/doc/install.texi
+++ b/gcc/doc/install.texi
@@ -1221,6 +1221,24 @@ ISA for floating-point arithmetics.  You can select either @samp{sse} which
 enables @option{-msse2} or @samp{avx} which enables @option{-mavx} by default.
 This option is only supported on i386 and x86-64 targets.
 
+@item --with-nan=@var{encoding}
+On MIPS targets, set the default encoding convention to use for the
+special not-a-number (NaN) IEEE 754 floating-point data.  The
+possibilities for @var{encoding} are:
+@table @code
+@item legacy
+Use the legacy encoding, as with the @option{-mnan=legacy} command-line
+option.
+@item 2008
+Use the 754-2008 encoding, as with the @option{-mnan=2008} command-line
+option.
+@end table
+To use this configuration option you must have an assembler version
+installed that supports the @option{-mnan=} command-line option too.
+In the absence of this configuration option the default convention is
+the legacy encoding, as when neither of the @option{-mnan=2008} and
+@option{-mnan=legacy} command-line options has been used.
+
 @item --with-divide=@var{type}
 Specify how the compiler should generate code for checking for
 division by zero.  This option is only supported on the MIPS target.
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 4457809..92cc250 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -750,7 +750,8 @@ Objective-C and Objective-C++ Dialects}.
 -mabi=@var{abi}  -mabicalls  -mno-abicalls @gol
 -mshared  -mno-shared  -mplt  -mno-plt  -mxgot  -mno-xgot @gol
 -mgp32  -mgp64  -mfp32  -mfp64  -mhard-float  -msoft-float @gol
--mno-float -msingle-float  -mdouble-float  @gol
+-mno-float  -msingle-float  -mdouble-float @gol
+-mabs=@var{mode}  -mnan=@var{encoding} @gol
 -mdsp  -mno-dsp  -mdspr2  -mno-dspr2 @gol
 -mmcu -mmno-mcu @gol
 -meva -mno-eva @gol
@@ -16324,6 +16325,48 @@ operations.
 Assume that the floating-point coprocessor supports double-precision
 operations.  This is the default.
 
+@item -mabs=2008
+@itemx -mabs=legacy
+@opindex mabs=2008
+@opindex mabs=legacy
+These options control the treatment of the special not-a-number (NaN)
+IEEE 754 floating-point data with the @code{abs.@i{fmt}} and
+@code{neg.@i{fmt}} machine instructions.
+
+By default or when the @option{-mabs=legacy} is used the legacy
+treatment is selected.  In this case these instructions are considered
+arithmetic and avoided where correct operation is required and the
+input operand might be a NaN.  A longer sequence of instructions that
+manipulate the sign bit of floating-point datum manually is used
+instead unless the @option{-ffinite-math-only} option has also been
+specified.
+
+The @option{-mabs=2008} option selects the IEEE 754-2008 treatment.  In
+this case these instructions are considered non-arithmetic and therefore
+operating correctly in all cases, including in particular where the
+input operand is a NaN.  These instructions are therefore always used
+for the respective operations.
+
+@item -mnan=2008
+@itemx -mnan=legacy
+@opindex mnan=2008
+@opindex mnan=legacy
+These options control the encoding of the special not-a-number (NaN)
+IEEE 754 floating-point data.
+
+The @option{-mnan=legacy} option selects the legacy encoding.  In this
+case quiet NaNs (qNaNs) are denoted by the first bit of their trailing
+significand field being 0, whereas signalling NaNs (sNaNs) are denoted
+by the first bit of their trailing significand field being 1.
+
+The @option{-mnan=2008} option selects the IEEE 754-2008 encoding.  In
+this case qNaNs are denoted by the first bit of their trailing
+significand field being 1, whereas sNaNs are denoted by the first bit of
+their trailing significand field being 0.
+
+The default is @option{-mnan=legacy} unless GCC has been configured with
+@option{--with-nan=2008}.
+
 @item -mllsc
 @itemx -mno-llsc
 @opindex mllsc