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Compiler Command-line Options

Command-line options

--allow_null_this, --no_allow_null_this

--alternative_tokens, --no_alternative_tokens

--anachronisms, --no_anachronisms

--apcs=qualifer...qualifier

--asm_dir=directory_name

--autoinline, --no_autoinline

--brief_diagnostics, --no_brief_diagnostics

--bss_threshold=num

-c

-C

--code_gen, --no_code_gen

--compatible=name

--compile_all_input, --no_compile_all_input

--create_pch=filename

-Dname[(parm-list)][=def]

--data_reorder, --no_data_reorder

--debug, --no_debug

--debug_macros, --no_debug_macros

--default_definition_visibility=visibility

--default_extension=ext

--dep_name, --no_dep_name

--depend=filename

--depend_dir=directory_name

--depend_format=string

--depend_single_line, --no_depend_single_line

--depend_system_headers, --no_depend_system_header

--depend_target=target

--diag_error=tag[,tag,...]

--diag_remark=tag[,tag,... ]

--diag_style={arm|ide|gnu}

--diag_suppress=tag[,tag,...]

--diag_suppress=optimizations

--diag_warning=tag[,tag,...]

--diag_warning=optimizations

--dollar, --no_dollar

-E

--emit_frame_directives, --no_emit_frame_directive

--errors=filename

--exceptions, --no_exceptions

--exceptions_unwind, --no_exceptions_unwind

--export_all_vtbl, --no_export_all_vtbl

--export_defs_implicitly, --no_export_defs_implici

--extended_initializers, --no_extended_initializer

--feedback=filename

--force_new_nothrow, --no_force_new_nothrow

--fp16_format=format

--friend_injection, --no_friend_injection

-g

--global_reg=reg_name[,reg_name,...]

--guiding_decls, --no_guiding_decls

--hide_all, --no_hide_all

-Idir[,dir,...]

--ignore_missing_headers

--implicit_include, --no_implicit_include

--implicit_include_searches, --no_implicit_include

--implicit_key_function, --no_implicit_key_functio

--implicit_typename, --no_implicit_typename

--import_all_vtbl

--inline, --no_inline

--interface_enums_are_32_bit

-Jdir[,dir,...]

--kandr_include

--library_interface=lib

--library_type=lib

--link_all_input, --no_link_all_input

--list_dir=directory_name

--locale=lang_country

--loose_implicit_cast

--lower_ropi, --no_lower_ropi

--lower_rwpi, --no_lower_rwpi

-M

--message_locale=lang_country[.codepage]

--min_array_alignment=opt

--multibyte_chars, --no_multibyte_chars

--multifile, --no_multifile

--multiply_latency=cycles

--narrow_volatile_bitfields

--nonstd_qualifier_deduction, --no_nonstd_qualifie

--old_specializations, --no_old_specializations

--old_style_preprocessing

--output_dir=directory_name

-P

--parse_templates, --no_parse_templates

--pch_messages, --no_pch_messages

--pch_verbose, --no_pch_verbose

--pending_instantiations=n

--phony_targets

--pointer_alignment=num

--preinclude=filename

--preprocess_assembly

--reassociate_saturation, --no_reassociate_saturat

--reduce_paths, --no_reduce_paths

--relaxed_ref_def, --no_relaxed_ref_def

--remove_unneeded_entities, --no_remove_unneeded_e

--restrict, --no_restrict

--retain=option

--rtti, --no_rtti

--rtti_data, --no_rtti_data

-S

--signed_bitfields, --unsigned_bitfields

--signed_chars, --unsigned_chars

--split_sections

--strict, --no_strict

--strict_warnings

--trigraphs, --no_trigraphs

--type_traits_helpers, --no_type_traits_helpers

--unaligned_access, --no_unaligned_access

--use_frame_pointer

--use_pch=filename

--using_std, --no_using_std

--version_number

--vfe, --no_vfe

--visibility_inlines_hidden

--vla, --no_vla

-W

--wchar, --no_wchar

--whole_program

--wrap_diagnostics, --no_wrap_diagnostics

Language Extensions

Compiler-specific Features

C and C++ Implementation Details

ARMv6 SIMD Instruction Intrinsics

Via File Syntax

Summary Table of GNU Language Extensions

Standard C Implementation Definition

Standard C++ Implementation Definition

C and C++ Compiler Implementation Limits

--reassociate_saturation, --no_reassociate_saturation

ARM Compiler toolchain v4.1 for µVision Compiler Reference

Home > Compiler Command-line Options > Command-line options > --reassociate_saturation, --no_reassociate_saturation

`--reassociate_saturation`, `--no_reassociate_saturation`

These options enable and disable more aggressive optimization in loops that use saturating addition, by either permitting or prohibiting re-association of saturation arithmetic.

Usage

Although potentially useful when vectorizing code, these options are not necessarily restricted to vectorization. For example, --reassociate_saturation could take effect when compiling with -O3 -Otime, even when automatic vectorization is not enabled.

Restriction

Saturating addition is not associative, so enabling re-association could affect the result with a reduction in accuracy.

Default

The default is --no_reassociate_saturation.

Example

The following code does not vectorize unless --reassociate_saturation is specified.

#include <dspfns.h>
int f(short *a, short *b)
{
    int i;
    int r = 0;
    for (i = 0; i < 100; i++)
         r=L_mac(r,a[i],b[i]);
    return r;
}

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Home > Compiler Command-line Options > Command-line options > --reassociate_saturation, --no_reassociate_saturation