C-SKY port: Documentation

2018-08-17  Sandra Loosemore  <sandra@codesourcery.com>

	C-SKY port: Documentation

	gcc/
	* doc/extend.texi (C-SKY Function Attributes): New section.
	* doc/invoke.texi (Option Summary): Add C-SKY options.
	(C-SKY Options): New section.
	* doc/md.texi (Machine Constraints): Document C-SKY constraints.

From-SVN: r263629

gcc/ChangeLog

+2018-08-17  Sandra Loosemore  <sandra@codesourcery.com>
+
+	C-SKY port: Documentation
+
+	* doc/extend.texi (C-SKY Function Attributes): New section.
+	* doc/invoke.texi (Option Summary): Add C-SKY options.
+	(C-SKY Options): New section.
+	* doc/md.texi (Machine Constraints): Document C-SKY constraints.
+
 2018-08-17  Jojo  <jijie_rong@c-sky.com>
 	    Huibin Wang  <huibin_wang@c-sky.com>
 	    Sandra Loosemore  <sandra@codesourcery.com>

gcc/doc/extend.texi

@@ -2324,6 +2324,7 @@ GCC plugins may provide their own attributes.
 * AVR Function Attributes::
 * Blackfin Function Attributes::
 * CR16 Function Attributes::
+* C-SKY Function Attributes::
 * Epiphany Function Attributes::
 * H8/300 Function Attributes::
 * IA-64 Function Attributes::
@@ -4147,6 +4148,38 @@ function entry and exit sequences suitable for use in an interrupt handler
 when this attribute is present.
 @end table
 
+@node C-SKY Function Attributes
+@subsection C-SKY Function Attributes
+
+These function attributes are supported by the C-SKY back end:
+
+@table @code
+@item interrupt
+@itemx isr
+@cindex @code{interrupt} function attribute, C-SKY
+@cindex @code{isr} function attribute, C-SKY
+Use these attributes to indicate that the specified function
+is an interrupt handler.
+The compiler generates function entry and exit sequences suitable for
+use in an interrupt handler when either of these attributes are present.
+
+Use of these options requires the @option{-mistack} command-line option
+to enable support for the necessary interrupt stack instructions.  They
+are ignored with a warning otherwise.  @xref{C-SKY Options}.
+
+@item naked
+@cindex @code{naked} function attribute, C-SKY
+This attribute allows the compiler to construct the
+requisite function declaration, while allowing the body of the
+function to be assembly code. The specified function will not have
+prologue/epilogue sequences generated by the compiler. Only basic
+@code{asm} statements can safely be included in naked functions
+(@pxref{Basic Asm}). While using extended @code{asm} or a mixture of
+basic @code{asm} and C code may appear to work, they cannot be
+depended upon to work reliably and are not supported.
+@end table
+
+
 @node Epiphany Function Attributes
 @subsection Epiphany Function Attributes
 

gcc/doc/invoke.texi

@@ -723,6 +723,16 @@ Objective-C and Objective-C++ Dialects}.
 -msim  -mint32  -mbit-ops
 -mdata-model=@var{model}}
 
+@emph{C-SKY Options}
+@gccoptlist{-march=@var{arch}  -mcpu=@var{cpu} @gol
+-mbig-endian  -EB  -mlittle-endian  -EL @gol
+-mhard-float  -msoft-float  -mfpu=@var{fpu}  -mdouble-float  -mfdivdu @gol
+-melrw  -mistack  -mmp  -mcp  -mcache  -msecurity  -mtrust @gol
+-mdsp  -medsp  -mvdsp @gol
+-mdiv  -msmart  -mhigh-registers  -manchor @gol
+-mpushpop  -mmultiple-stld  -mconstpool  -mstack-size  -mccrt @gol
+-mbranch-cost=@var{n}  -mcse-cc  -msched-prolog}
+
 @emph{Darwin Options}
 @gccoptlist{-all_load  -allowable_client  -arch  -arch_errors_fatal @gol
 -arch_only  -bind_at_load  -bundle  -bundle_loader @gol
@@ -14633,6 +14643,7 @@ platform.
 * C6X Options::
 * CRIS Options::
 * CR16 Options::
+* C-SKY Options::
 * Darwin Options::
 * DEC Alpha Options::
 * FR30 Options::
@@ -17757,6 +17768,198 @@ However, @samp{far} is not valid with @option{-mcr16c}, as the
 CR16C architecture does not support the far data model.
 @end table
 
+@node C-SKY Options
+@subsection C-SKY Options
+@cindex C-SKY Options
+
+GCC supports these options when compiling for C-SKY V2 processors.
+
+@table @gcctabopt
+
+@item -march=@var{arch}
+@opindex march=
+Specify the C-SKY target architecture.  Valid values for @var{arch} are:
+@samp{ck801}, @samp{ck802}, @samp{ck803}, @samp{ck807}, and @samp{ck810}.
+The default is @samp{ck810}.
+
+@item -mcpu=@var{cpu}
+@opindex mcpu=
+Specify the C-SKY target processor.  Valid values for @var{cpu} are:
+@samp{ck801}, @samp{ck801t},
+@samp{ck802}, @samp{ck802t}, @samp{ck802j},
+@samp{ck803}, @samp{ck803h}, @samp{ck803t}, @samp{ck803ht},
+@samp{ck803f}, @samp{ck803fh}, @samp{ck803e}, @samp{ck803eh},
+@samp{ck803et}, @samp{ck803eht}, @samp{ck803ef}, @samp{ck803efh},
+@samp{ck803ft}, @samp{ck803eft}, @samp{ck803efht}, @samp{ck803r1},
+@samp{ck803hr1}, @samp{ck803tr1}, @samp{ck803htr1}, @samp{ck803fr1},
+@samp{ck803fhr1}, @samp{ck803er1}, @samp{ck803ehr1}, @samp{ck803etr1},
+@samp{ck803ehtr1}, @samp{ck803efr1}, @samp{ck803efhr1}, @samp{ck803ftr1},
+@samp{ck803eftr1}, @samp{ck803efhtr1},
+@samp{ck803s}, @samp{ck803st}, @samp{ck803se}, @samp{ck803sf},
+@samp{ck803sef}, @samp{ck803seft},
+@samp{ck807e}, @samp{ck807ef}, @samp{ck807}, @samp{ck807f},
+@samp{ck810e}, @samp{ck810et}, @samp{ck810ef}, @samp{ck810eft},
+@samp{ck810}, @samp{ck810v}, @samp{ck810f}, @samp{ck810t}, @samp{ck810fv},
+@samp{ck810tv}, @samp{ck810ft}, and @samp{ck810ftv}.
+
+@item -mbig-endian
+@opindex mbig-endian
+@itemx -EB
+@opindex -EB
+@itemx -mlittle-endian
+@opindex mlittle-endian
+@itemx -EL
+@opindex -EL
+
+Select big- or little-endian code.  The default is little-endian.
+
+@item -mhard-float
+@opindex mhard-float
+@itemx -msoft-float
+@opindex msoft-float
+
+Select hardware or software floating-point implementations.
+The default is soft float.
+
+@item -mdouble-float
+@itemx -mno-double-float
+@opindex mdouble-float
+When @option{-mhard-float} is in effect, enable generation of
+double-precision float instructions.  This is the default except
+when compiling for CK803.
+
+@item -mfdivdu
+@itemx -mno-fdivdu
+@opindex mfdivdu
+When @option{-mhard-float} is in effect, enable generation of
+@code{frecipd}, @code{fsqrtd}, and @code{fdivd} instructions.
+This is the default except when compiling for CK803.
+
+@item -mfpu=@var{fpu}
+@opindex mfpu=
+Select the floating-point processor.  This option can only be used with
+@option{-mhard-float}.
+Values for @var{fpu} are
+@samp{fpv2_sf} (equivalent to @samp{-mno-double-float -mno-fdivdu}),
+@samp{fpv2} (@samp{-mdouble-float -mno-divdu}), and
+@samp{fpv2_divd} (@samp{-mdouble-float -mdivdu}).
+
+@item -melrw
+@itemx -mno-elrw
+@opindex melrw
+Enable the extended @code{lrw} instruction.  This option defaults to on
+for CK801 and off otherwise.
+
+@item -mistack
+@itemx -mno-istack
+@opindex mistack
+Enable interrupt stack instructions; the default is off.
+
+The @option{-mistack} option is required to handle the
+@code{interrupt} and @code{isr} function attributes
+(@pxref{C-SKY Function Attributes}).
+
+@item -mmp
+@opindex mmp
+Enable multiprocessor instructions; the default is off.
+
+@item -mcp
+@opindex mcp
+Enable coprocessor instructions; the default is off.
+
+@item -mcache
+@opindex mcache
+Enable coprocessor instructions; the default is off.
+
+@item -msecurity
+@opindex msecurity
+Enable C-SKY security instructions; the default is off.
+
+@item -mtrust
+@opindex mtrust
+Enable C-SKY trust instructions; the default is off.
+
+@item -mdsp
+@opindex mdsp
+@itemx -medsp
+@opindex medsp
+@itemx -mvdsp
+@opindex mvdsp
+Enable C-SKY DSP, Enhanced DSP, or Vector DSP instructions, respectively.
+All of these options default to off.
+
+@item -mdiv
+@itemx -mno-div
+@opindex mdiv
+Generate divide instructions.  Default is off.
+
+@item -msmart
+@itemx -mno-smart
+@opindex msmart
+Generate code for Smart Mode, using only registers numbered 0-7 to allow
+use of 16-bit instructions.  This option is ignored for CK801 where this
+is the required behavior, and it defaults to on for CK802.
+For other targets, the default is off.
+
+@item -mhigh-registers
+@itemx -mno-high-registers
+@opindex mhigh-registers
+Generate code using the high registers numbered 16-31.  This option
+is not supported on CK801, CK802, or CK803, and is enabled by default
+for other processors.
+
+@item -manchor
+@itemx -mno-anchor
+@opindex manchor
+Generate code using global anchor symbol addresses.
+
+@item -mpushpop
+@itemx -mno-pushpop
+@opindex mpushpop
+Generate code using @code{push} and @code{pop} instructions.  This option
+defaults to on.
+
+@item -mmultiple-stld
+@itemx -mstm
+@itemx -mno-multiple-stld
+@itemx -mno-stm
+@opindex mmultiple-stld
+Generate code using @code{stm} and @code{ldm} instructions.  This option
+isn't supported on CK801 but is enabled by default on other processors.
+
+@item -mconstpool
+@itemx -mno-constpool
+@opindex mconstpool
+Create constant pools in the compiler instead of deferring it to the
+assembler.  This option is the default and required for correct code
+generation on CK801 and CK802, and is optional on other processors.
+
+@item -mstack-size
+@item -mno-stack-size
+@opindex mstack-size
+Emit @code{.stack_size} directives for each function in the assembly
+output.  This option defaults to off.
+
+@item -mccrt
+@itemx -mno-ccrt
+@opindex mccrt
+Generate code for the C-SKY compiler runtime instead of libgcc.  This
+option defaults to off.
+
+@item -mbranch-cost=@var{n}
+@opindex mbranch-cost=
+Set the branch costs to roughly @code{n} instructions.  The default is 1.
+
+@item -msched-prolog
+@itemx -mno-sched-prolog
+@opindex msched-prolog
+Permit scheduling of function prologue and epilogue sequences.  Using
+this option can result in code that is not compliant with the C-SKY V2 ABI
+prologue requirements and that cannot be debugged or backtraced.
+It is disabled by default.
+
+@end table
+
 @node Darwin Options
 @subsection Darwin Options
 @cindex Darwin options

gcc/doc/md.texi

@@ -2132,6 +2132,42 @@ Check for 64 bits wide constants for add/sub instructions
 Floating point constant that is legal for store immediate
 @end table
 
+@item C-SKY---@file{config/csky/constraints.md}
+@table @code
+
+@item a
+The mini registers r0 - r7.
+
+@item b
+The low registers r0 - r15.
+
+@item c
+C register.
+
+@item y
+HI and LO registers.
+
+@item l
+LO register.
+
+@item h
+HI register.
+
+@item v
+Vector registers.
+
+@item z
+Stack pointer register (SP).
+@end table
+
+@ifset INTERNALS
+The C-SKY back end supports a large set of additional constraints
+that are only useful for instruction selection or splitting rather
+than inline asm, such as constraints representing constant integer
+ranges accepted by particular instruction encodings.
+Refer to the source code for details.
+@end ifset
+
 @item Epiphany---@file{config/epiphany/constraints.md}
 @table @code
 @item U16