ic960 Compiler Driver

ic960 is a driver program that manages invocation of the preprocessor, compiler proper, assembler and linker. The invocation syntax is:

ic960 { - | / } [ -option ] ... file ...

Each invocation option must be preceded by a - character. (On DOS, you can also use a / character.) Click on option for information on compiler driver options. All options that take an argument allow optional white space between the option and the argument. When conflicting options are given, the last one specified is used. The compiler driver passes the following linker options and their arguments to the linker: gcdm, L, l, m, r, s, T, u and x.

The compilation system determines each input file's type by its filename extension:

The compilation system passes any other filename to the linker, which determines whether the file is an object file, library or configuration file by its contents.

Other invocation command elements are taken to be either linker options or object modules, typically produced by an earlier ic960 invocation, or perhaps libraries of compatible routines. These modules, together with the result of any compilations specified, are linked (in the order given) to produce an executable program.

When generating COFF modules, the default output filename is a.out. When generating ELF/DWARF modules, the default filename is e.out.

ic960 Driver Options

Each option requires an option delimiter (- or /). All options that take an argument allow optional white space between the option and argument. When conflicting options are given, the last one specified is used. For information about an option, click on the option name (underlined).

The ic960 driver also accepts certain linker options.

A { CA | CF | HA | HD | HT | JA | JD | JF | KA | KB | RP | SA | SB }

(Architecture)

Compile code for a particular model of the i960 processor. If the environment variable I960ARCH is set and non-empty, its value is the default architecture. Otherwise the default is KB.

a (ANSI)
Flag non-standard (that is, non-ANSI) constructs. Using a disables inline assembly language statements and can override the w (Diagnostic) option. This option causes the preprocessor macros __STRICT_ANSI__ and __STRICT_ANSI to be defined.

b size (Limit Optimizations)
Limit global optimizations for functions exceeding size instructions. size is a positive decimal integer.

C (Keep Comments)
Keep comments in preprocessor output. Works only with E or P.

Dsymbol[=value] (Define)
Define a macro with a given value. If =value is omitted, symbol is defined to be 1.

Fcoff | Felf (OMF)
Generate COFF or ELF objects. Fcoff is the default.

F arg[,arg]...
(Fine-Tune Optimization)
Enable or disable selected optimizations. arg is one of:

ai | noai
Enables/disables procedure in-lining. Performed only at optimization level 2. Suppressing in-lining can reduce code size and increase compilation speed.
ca | noca
Enables/disables code alignment; generate (do not generate) alignment directives prior to labels that are not entered from above.
cb | nocb
Enables/disables use of compare and branch instructions.
lp
Leaf procedures. Enables code generation of functions using the bal calling sequence at optimization level 1 or 2. Default at level 1.
nolp
Disables code generation of functions using the bal calling sequence at optimization level 1 or 2. Default at level 2.
sa | nosa
Determines whether or not the compiler will risk generating memory references which are not provably aligned. If nosa is in effect, the compiler occasionally generates potentially unaligned references when it seems advantageous to do so. When sa is enabled, sequences of smaller memory references are used instead of larger ones which might not be correctly aligned. The default is sa for C-series and J-series processors.
sb
Superblock formation; enabled by default under program-wide optimization.
nosb
Disables superblock formation.
space | nospace
Enable/disable optimizations for memory space savings.
tce
Enables conversion of tail calls into branch instructions at optimization level 1 or 2.
notce
Disables conversion of tail calls at level 1 or 2. This is the default at optimization level 1.

fdb (Program Database)
All modules subject to program-wide optimization must be initially compiled with the fdb option. This option causes the insertion of program database information in the object modules, and it implies a minimum module-local optimization level of O1 (although higher module-local optimization levels are allowed).

This option does not otherwise change the code or data generated for the object modules in any way; it simply makes available to the global decision making and optimization process information collected during initial compilation of the modules.

Before using the fdb option, you should read Chapter 4, Program-Wide Analysis and Optimization, and Chapter 6, gcdm Decision Maker Option, in the i960 Processor Compiler User's Guide.

If you intend to use execution profiles when optimizing your application, you should read Chapter 5, Profile Data Merging and Data Format, in the i960 Processor Compiler User's Guide.

fprof (Instrument)
This option inserts execution profile instrumentation code into the module(s) during compilation, so that when the linked program is executed, a profile can be collected.

It also implies fdb, which causes the insertion of program database information in the object modules, and it implies a minimum module-local optimization level of O1.

When you compile with the fprof option, a special profiling library required for profile collection (libqf) is linked automatically. If your target environment does not support file I/O, you must explicitly link an alternate profiling library (libq). The profiling libraries provided are identified in Chapter 2 of the i960 Processor Library Supplement.

Note that when the fprof compiler option is used in this manner (as distinct from the corresponding +fprof gcdm Decision Maker option) the generated object module contains code that is unsuitable for linking into programs which are not supposed to collect profile information. To solve this problem, and avoid having inappropriate instrumentation in widely used libraries, for example, use +fprof with the gcdm,subst option. (The gcdm option is described in the gcdm Decision Maker Option section of this hypertext.)

Before using the fprof option, you should read Chapter 4, Program-Wide Analysis and Optimization, and Chapter 5, Profile Data Merging and Data Format, in the i960 Processor Compiler User's Guide.

f[no-]arg (Enable/Disable Optimization)

Enable/disable optimization. arg is one of:

bbr
enable basic block rearrangement.
coalesce
coalesce adjacent memory references.
coerce
enable byte/short optimization.
cond-mismatch
allow type mismatch in operands of the ?: operator.
condxform
enable 80960 conditional instructions.
constprop
enable constant propagation and folding.
copyprop
enable copy propagation.
cse-follow-jumps
enable a limited form of global CSE.
cse-skip-blocks
enable a limited form of global CSE.
expensive-optimizations
enable some minor optimizations.
force-addr
place address constants in registers before use.
int-alias-ptr
indicates to the compiler that pointer objects may be referenced as 32-bit integers and vice versa.
int-alias-real
indicates to the compiler that float, double and long double objects (or parts thereof) may be referenced as 32-bit integers and vice versa.
int-alias-short
indicates to the compiler that four-byte integer objects may be referenced as two-byte objects and vice versa.
keep-inline-functions
emit out-of-line code for inlined functions.
marry_mem
rejoin multi-word moves split by fsplit_mem.
rerun-cse-after-loop
reiterate CSE after loop optimization.
schedule-insns
perform pre-register-allocation scheduling.
schedule-insns2
perform post-register-allocation scheduling.
shadow-globals
shadow memory locations in registers.
shadow-mem
like shadow-globals, but more thorough.
space-opt
optimize for code size.
split_mem
split multi-word moves for copy propagation.
strength-reduce
enable loop strength reduction.
thread-jumps
enable an advanced branch optimization.
unroll-all-loops
unroll all loops.
unroll-loops
unroll loops where deemed beneficial.
volatile
treat indirect memory references as volatile.
volatile-global
treat all memory references as volatile.
writable-strings
place string literals in .data section.

G arg[,arg]... (Generate)
Specifies a code generation option. arg is one of:

abi
Generate ABI-conformant code.
ac=n
Align structures on the byte boundary specified by n, where n is either 1, 2, 4, 8, or 16.
bc
Generate code that is backward-compatible with releases of ic960 before Release 3.0.
be
Generate code to run in big-endian memory. This option causes the preprocessor symbol __i960_BIG_ENDIAN__ to be defined.
cave
Generate all functions as CAVE secondary.
{cs | cu}
Treat char data types as signed or unsigned, respectively. If signed (the default), the preprocessor symbol __SIGNED_CHARS__ is defined. If unsigned, the preprocessor symbol __CHAR_UNSIGNED__ is defined.
dc
Employ the relaxed (common) ref-def model for defining uninitialized data. This is the default.
ds
Employ the strict ref-def model for defining uninitialized data.
pc
Generates position-independent code. Causes __PIC to be defined.
pd
Generates position-independent data. Causes __PID to be defined.
pr
Reserves register g12 containing the position-independent data (PID) bias value.
wait=n
Specifies wait-state for memory accesses. n is 0..32.
xc
Specifies that all external calls in the module use the extended-call mechanism.

g [level] (Debug)
Put symbolic debug information into the object module. level is:

0
disables debug information (default).
1 or 2
minimal debug information. (Same as g with no argument.)
3
verbose debug information (ELF/DWARF only).

gcdm,arg[,arg]... (Decision Maker)

Invoke gcdm960 decision maker to perform optimization or related tasks. Click gcdm option for information on this option.

h (Help)
Print a summary of ic960 driver options and exit without processing any files.

I dir (Searchinclude)
Add the directory dir to the search list for #include files.

i filename (Preinclude)
Include the specified source file as if a #include of that file existed at line zero of each primary source file.

Jarg[,arg]... (Miscellaneous)
Use the J (Miscellaneous) option to specify miscellaneous controls. Two such controls are gd (issue gcc960-style diagnostics) and nogd (issue ic960-style diagnostics).

jnum (Errata)
Use the j (Errata) option to cause the compilation system to generate code with workarounds for specified processor errata. A num argument of 1 generates code to work around the Cx processors' DMA errata.

M (Mix)
Mix C source text as comments in the assembly language output. Works only with S.

n | Q | P | E | S | c (Stop-After)
Stop after the specified compilation phase. These options are used as follows:

n
Terminate after syntax and semantic checking.
Q
Terminate after preprocessing; produce an include file dependency list.
P
Terminate after preprocessing. Write preprocessor output without line number directives to a file.
E
Terminate after preprocessing. Write preprocessor output with line number directives to standard output.
S
Terminate after generating assembly code.
c
Terminate after generating an object file.

O level (Optimize)
Specify the optimization level to be used. Supported levels are 0, 1 and 2.

0
Turns optimization off, and additionally disables default optimizations that may interfere with debugging. This is the default setting if you use the g (Debug) option with a non-zero debug level argument.
1
This option turns on basic optimizations, including: advanced register allocation, common subexpression elimination, loop invariant code motion, expression simplification and instruction combination, jump optimization, dead-code elimination, tail-call elimination, leaf-procedure optimization, and i960 processor-specific peephole optimization. This is the default setting if you do not use the g (Debug) option and when you use the fdb (Program Database) or fprof (Instrument) options.
2
This level includes the O1 optimizations described above, and the following additional optimizations:
fcoalesce, fcoerce, fcondxform, fconstprop, fcopyprop, fcse-follow-jumps, fcse-skip-blocks, fexpensive-optimizations, finline-functions, fmarry_mem, frerun-cse-after-loop, fschedule-insns, fschedule-insns2, fshadow-globals, fshadow-mem, fsplit_mem, fstrength-reduce, funroll-loops.

o filename (Output)
Names the output file, which can be either preprocessing output, assembly code, an object module, or linker output.

U symbol (Undefine)
Undefine a preprocessor symbol. By default, no symbols are undefined.

V (Version)
Display a version message and other information. By default, the compiler does not display version information.

v960 (Version, terminate)
Display version and terminate.

v (Verbose)
Display the driver's invocation command, and the preprocessor, compiler, assembler, and linker phase invocations. By default, the driver does not display individual phase invocations.

w level (Diagnostic Level)
Control the level of diagnostics produced by the compiler. Choose one of the following for level: use 0 to enable remark, warning and error messages; use 1 to enable warning and error messages and suppress remark messages; and use 2 to enable error messages and suppress remark and warning messages. The default level is 1.

W phase,arg[,arg]... (Pass)
Pass arguments to the preprocessor, compiler, assembler or linker. For phase, p indicates the preprocessor, c indicates the compiler, a indicates the assembler and l indicates the linker. arg is an argument to be passed. If the argument contains spaces, you must enclose the argument in quotation characters (" ").

W [no-]arg (Warnings)
Enables/disables warnings. With no arg, this option prints extra warning messages for certain events, including:

longjmp() warnings
Warn if a nonvolatile automatic variable might be changed by a call to longjmp(). These warnings are possible only in an optimizing compilation.
The compiler sees only the calls to setjmp(). It cannot know where longjmp() will be called; in fact a signal handler could call it at any point in the code. As a result, you may get a warning even when there is in fact no problem because longjmp() cannot actually be called at the place that would cause a problem.
return and return(value)
Warn if a function can return either with or without a value. (Falling off the end of the function body is considered returning with a value.)
null effect
Warn if an expression-statement contains no side effects.
no-op comparison
Warn if an unsigned value is compared against zero with < or <=.
between-ness comparison
Warn if a comparison like x<=y<=z is used; this is equivalent to {(x<=y ? 1 : 0) <=z}, which is a different interpretation from that of ordinary mathematical notation.
obsolete storage class specification
Warn if storage-class specifiers like static are not the first things in a declaration. According to the ANSI C standard, this usage is obsolescent.
partially bracketed initializer
Warn if an aggregate has a partly bracketed initializer.

arg can be:

aggregate-return
Warn if any functions return structs or unions.

all
Enable several useful warnings, as indicated in the list below. Has no Wno-all form.

cast-align
Warn if a pointer cast may not have required alignment.

cast-qual
Warn if a pointer cast removes a type qualifier.

char-subscripts
Warn if an array subscript has type char. Enabled by Wall.

comment
Warn whenever /* occurs within a comment. Enabled by Wall.

conversion
Warn if a prototyped parameter causes a different conversion than if not prototyped.

error
Treat all warnings as errors.

format
Check types of printf family arguments at compile time. Enabled by Wall.

id-clash-n
Warn if two identifiers match in the first n characters. Has no Wno-all form.

implicit
Warn if a function is used before being declared. Enabled by Wall.

missing-braces
Warn if an aggregate initializer is not fully braced.

missing-prototypes
Warn if a function is defined before it is prototyped. Enabled by Wall.

nested-externs
Warn if an extern declaration is seen within a function.

parentheses
Warn if parentheses are suggested around an expression. Enabled by Wall.

pointer-arith
Warn if the size of a function type or type void is used.

redundant-decls
Warn if an object is declared twice in the same scope.

return-type
Warn if any function implicitly returns int, and if a non-void function does not return a value. Enabled by Wall.

shadow
Warn if a local variable shadows another local variable.

strict-prototypes
Warn if a function is declared without a prototype.

switch
Warn if a switch statement on an enumeration type does not have a case for each enumerator. Enabled by Wall.

traditional
Warn about constructs that behave differently under traditional C and ANSI C.

trigraphs
Warn if any trigraphs are encountered. Enabled by Wall.

uninitialized
Warn if use of an uninitialized local variable is detected. Enabled by Wall.

unused
Warn about objects that are never used. Enabled by Wall.

write-strings
Warn if string constants are used in a writable context.

Yd,dir (Specify PDB)
Specifies the name of a program database directory.

Z filename (Listname)
Directs the listing to the named file. This option implies the z (List) option and s argument.

z arg... (List)
Create a listing file with the suffix .L for each C source file. arg is a string containing one or more of the following letters:

c
Add conditionally noncompiled source text to the primary source text listing.
i
Add included source text to the primary source text listing.
m
Add macro-expanded preprocessor lines to the primary source text listing.
o
Add assembly language code generated by the compiler to the listing file.
s
List the primary source text.

Linker Options

L dir
Add the directory dir to the linker's search list for libraries.

l lib
Add the library lib to the linker's list of input libraries.

m
Create a linker map file.

r
Retain relocation information in the object file produced by the linker.

s
Strip line number and symbol table entries from the object file produced by the linker.

T target
Select a configuration file that names a startup routine, system call library, and linker directive file for a specific run-time environment.

u symbol
Introduce an undefined symbol to the linker.

x
Remove local symbols from the symbol table in the linker's output.

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