binutils-gdb/gas/doc/c-sh.texi

@c Copyright 1991, 1992, 1993, 1994, 1995, 1997, 2001, 2003, 2004,
@c 2005, 2008, 2010, 2011  Free Software Foundation, Inc.
@c This is part of the GAS manual.
@c For copying conditions, see the file as.texinfo.
@page
@node SH-Dependent
@chapter Renesas / SuperH SH Dependent Features

@cindex SH support
@menu
* SH Options::              Options
* SH Syntax::               Syntax
* SH Floating Point::       Floating Point
* SH Directives::           SH Machine Directives
* SH Opcodes::              Opcodes
@end menu

@node SH Options
@section Options

@cindex SH options
@cindex options, SH
@code{@value{AS}} has following command-line options for the Renesas
(formerly Hitachi) / SuperH SH family.

@table @code
@kindex --little
@kindex --big
@kindex --relax
@kindex --small
@kindex --dsp
@kindex --renesas
@kindex --allow-reg-prefix

@item --little
Generate little endian code.

@item --big
Generate big endian code.

@item --relax
Alter jump instructions for long displacements.

@item --small
Align sections to 4 byte boundaries, not 16.

@item --dsp
Enable sh-dsp insns, and disable sh3e / sh4 insns.

@item --renesas
Disable optimization with section symbol for compatibility with
Renesas assembler.

@item --allow-reg-prefix
Allow '$' as a register name prefix.

@kindex --fdpic
@item --fdpic
Generate an FDPIC object file.

@item --isa=sh4 | sh4a
Specify the sh4 or sh4a instruction set.
@item --isa=dsp
Enable sh-dsp insns, and disable sh3e / sh4 insns.
@item --isa=fp
Enable sh2e, sh3e, sh4, and sh4a insn sets.
@item --isa=all
Enable sh1, sh2, sh2e, sh3, sh3e, sh4, sh4a, and sh-dsp insn sets.

@item -h-tick-hex
Support H'00 style hex constants in addition to 0x00 style.

@end table

@node SH Syntax
@section Syntax

@menu
* SH-Chars::                Special Characters
* SH-Regs::                 Register Names
* SH-Addressing::           Addressing Modes
@end menu

@node SH-Chars
@subsection Special Characters

@cindex line comment character, SH
@cindex SH line comment character
@samp{!} is the line comment character.

@cindex line separator, SH
@cindex statement separator, SH
@cindex SH line separator
You can use @samp{;} instead of a newline to separate statements.

If a @samp{#} appears as the first character of a line then the whole
line is treated as a comment, but in this case the line could also be
a logical line number directive (@pxref{Comments}) or a preprocessor
control command (@pxref{Preprocessing}).

@cindex symbol names, @samp{$} in
@cindex @code{$} in symbol names
Since @samp{$} has no special meaning, you may use it in symbol names.

@node SH-Regs
@subsection Register Names

@cindex SH registers
@cindex registers, SH
You can use the predefined symbols @samp{r0}, @samp{r1}, @samp{r2},
@samp{r3}, @samp{r4}, @samp{r5}, @samp{r6}, @samp{r7}, @samp{r8},
@samp{r9}, @samp{r10}, @samp{r11}, @samp{r12}, @samp{r13}, @samp{r14},
and @samp{r15} to refer to the SH registers.

The SH also has these control registers:

@table @code
@item pr
procedure register (holds return address)

@item pc
program counter

@item mach
@itemx macl
high and low multiply accumulator registers

@item sr
status register

@item gbr
global base register

@item vbr
vector base register (for interrupt vectors)
@end table

@node SH-Addressing
@subsection Addressing Modes

@cindex addressing modes, SH
@cindex SH addressing modes
@code{@value{AS}} understands the following addressing modes for the SH.
@code{R@var{n}} in the following refers to any of the numbered
registers, but @emph{not} the control registers.

@table @code
@item R@var{n}
Register direct

@item @@R@var{n}
Register indirect

@item @@-R@var{n}
Register indirect with pre-decrement

@item @@R@var{n}+
Register indirect with post-increment

@item @@(@var{disp}, R@var{n})
Register indirect with displacement

@item @@(R0, R@var{n})
Register indexed

@item @@(@var{disp}, GBR)
@code{GBR} offset

@item @@(R0, GBR)
GBR indexed

@item @var{addr}
@itemx @@(@var{disp}, PC)
PC relative address (for branch or for addressing memory).  The
@code{@value{AS}} implementation allows you to use the simpler form
@var{addr} anywhere a PC relative address is called for; the alternate
form is supported for compatibility with other assemblers.

@item #@var{imm}
Immediate data
@end table

@node SH Floating Point
@section Floating Point

@cindex floating point, SH (@sc{ieee})
@cindex SH floating point (@sc{ieee})
SH2E, SH3E and SH4 groups have on-chip floating-point unit (FPU). Other
SH groups can use @code{.float} directive to generate @sc{ieee} 
floating-point numbers. 

SH2E and SH3E support single-precision floating point calculations as 
well as entirely PCAPI compatible emulation of double-precision 
floating point calculations. SH2E and SH3E instructions are a subset of
the floating point calculations conforming to the IEEE754 standard.

In addition to single-precision and double-precision floating-point 
operation capability, the on-chip FPU of SH4 has a 128-bit graphic 
engine that enables 32-bit floating-point data to be processed 128 
bits at a time. It also supports 4 * 4 array operations and inner 
product operations. Also, a superscalar architecture is employed that 
enables simultaneous execution of two instructions (including FPU 
instructions), providing performance of up to twice that of 
conventional architectures at the same frequency.

@node SH Directives
@section SH Machine Directives

@cindex SH machine directives
@cindex machine directives, SH
@cindex @code{uaword} directive, SH
@cindex @code{ualong} directive, SH

@table @code
@item uaword
@itemx ualong
@code{@value{AS}} will issue a warning when a misaligned @code{.word} or
@code{.long} directive is used.  You may use @code{.uaword} or
@code{.ualong} to indicate that the value is intentionally misaligned.
@end table

@node SH Opcodes
@section Opcodes

@cindex SH opcode summary
@cindex opcode summary, SH
@cindex mnemonics, SH
@cindex instruction summary, SH
For detailed information on the SH machine instruction set, see
@cite{SH-Microcomputer User's Manual} (Renesas) or
@cite{SH-4 32-bit CPU Core Architecture} (SuperH) and
@cite{SuperH (SH) 64-Bit RISC Series} (SuperH).

@code{@value{AS}} implements all the standard SH opcodes.  No additional
pseudo-instructions are needed on this family.  Note, however, that
because @code{@value{AS}} supports a simpler form of PC-relative
addressing, you may simply write (for example)

@example
mov.l  bar,r0
@end example

@noindent
where other assemblers might require an explicit displacement to
@code{bar} from the program counter:

@example
mov.l  @@(@var{disp}, PC)
@end example

@ifset SMALL
@c this table, due to the multi-col faking and hardcoded order, looks silly
@c except in smallbook.  See comments below "@set SMALL" near top of this file.

Here is a summary of SH opcodes:

@page
@smallexample
@i{Legend:}
Rn        @r{a numbered register}
Rm        @r{another numbered register}
#imm      @r{immediate data}
disp      @r{displacement}
disp8     @r{8-bit displacement}
disp12    @r{12-bit displacement}

add #imm,Rn                    lds.l @@Rn+,PR              
add Rm,Rn                      mac.w @@Rm+,@@Rn+           
addc Rm,Rn                     mov #imm,Rn                 
addv Rm,Rn                     mov Rm,Rn                   
and #imm,R0                    mov.b Rm,@@(R0,Rn)          
and Rm,Rn                      mov.b Rm,@@-Rn              
and.b #imm,@@(R0,GBR)           mov.b Rm,@@Rn               
bf disp8                       mov.b @@(disp,Rm),R0        
bra disp12                     mov.b @@(disp,GBR),R0       
bsr disp12                     mov.b @@(R0,Rm),Rn          
bt disp8                       mov.b @@Rm+,Rn              
clrmac                         mov.b @@Rm,Rn               
clrt                           mov.b R0,@@(disp,Rm)        
cmp/eq #imm,R0                 mov.b R0,@@(disp,GBR)       
cmp/eq Rm,Rn                   mov.l Rm,@@(disp,Rn)        
cmp/ge Rm,Rn                   mov.l Rm,@@(R0,Rn)          
cmp/gt Rm,Rn                   mov.l Rm,@@-Rn              
cmp/hi Rm,Rn                   mov.l Rm,@@Rn               
cmp/hs Rm,Rn                   mov.l @@(disp,Rn),Rm        
cmp/pl Rn                      mov.l @@(disp,GBR),R0       
cmp/pz Rn                      mov.l @@(disp,PC),Rn        
cmp/str Rm,Rn                  mov.l @@(R0,Rm),Rn          
div0s Rm,Rn                    mov.l @@Rm+,Rn              
div0u                          mov.l @@Rm,Rn               
div1 Rm,Rn                     mov.l R0,@@(disp,GBR)       
exts.b Rm,Rn                   mov.w Rm,@@(R0,Rn)          
exts.w Rm,Rn                   mov.w Rm,@@-Rn              
extu.b Rm,Rn                   mov.w Rm,@@Rn               
extu.w Rm,Rn                   mov.w @@(disp,Rm),R0        
jmp @@Rn                        mov.w @@(disp,GBR),R0       
jsr @@Rn                        mov.w @@(disp,PC),Rn        
ldc Rn,GBR                     mov.w @@(R0,Rm),Rn          
ldc Rn,SR                      mov.w @@Rm+,Rn              
ldc Rn,VBR                     mov.w @@Rm,Rn               
ldc.l @@Rn+,GBR                 mov.w R0,@@(disp,Rm)        
ldc.l @@Rn+,SR                  mov.w R0,@@(disp,GBR)       
ldc.l @@Rn+,VBR                 mova @@(disp,PC),R0         
lds Rn,MACH                    movt Rn                     
lds Rn,MACL                    muls Rm,Rn                  
lds Rn,PR                      mulu Rm,Rn                  
lds.l @@Rn+,MACH                neg Rm,Rn                   
lds.l @@Rn+,MACL                negc Rm,Rn                  
@page
nop                            stc VBR,Rn                
not Rm,Rn                      stc.l GBR,@@-Rn           
or #imm,R0                     stc.l SR,@@-Rn            
or Rm,Rn                       stc.l VBR,@@-Rn           
or.b #imm,@@(R0,GBR)            sts MACH,Rn               
rotcl Rn                       sts MACL,Rn               
rotcr Rn                       sts PR,Rn                 
rotl Rn                        sts.l MACH,@@-Rn          
rotr Rn                        sts.l MACL,@@-Rn          
rte                            sts.l PR,@@-Rn            
rts                            sub Rm,Rn                 
sett                           subc Rm,Rn                
shal Rn                        subv Rm,Rn                
shar Rn                        swap.b Rm,Rn              
shll Rn                        swap.w Rm,Rn              
shll16 Rn                      tas.b @@Rn                
shll2 Rn                       trapa #imm                
shll8 Rn                       tst #imm,R0               
shlr Rn                        tst Rm,Rn                 
shlr16 Rn                      tst.b #imm,@@(R0,GBR)     
shlr2 Rn                       xor #imm,R0               
shlr8 Rn                       xor Rm,Rn                 
sleep                          xor.b #imm,@@(R0,GBR)     
stc GBR,Rn                     xtrct Rm,Rn               
stc SR,Rn
@end smallexample
@end ifset

@ifset Renesas-all
@ifclear GENERIC
@raisesections
@end ifclear
@end ifset