[patch] AVR: Add -mfuse-ifelse for better control of pass avr-ifelse
Georg-Johann Lay <[email protected]>
| Newsgroups | gmane.comp.gcc.patches |
|---|---|
| Message-ID | <[email protected]> |
This patch adds -m[no-]fuse-ifelse as new optimization, so that the avr-ifelse pass can be deactivated. Ok for trunk? Johann -- gcc/ * config/avr/avr.opt (-mfuse-ifelse): New option. * config/avr/avr-passes.cc (avr_pass_ifelse::gate): Don't return true when avropt_fuse_ifelse is false. * config/avr/avr.opt.urls (mfuse-ifelse): Add URL. * common/config/avr/avr-common.cc (avr_option_optimization_table) [OPT_LEVELS_1_PLUS]: Set OPT_mfuse_ifelse to 1. * doc/invoke.texi (AVR Options): Document it.
avropt-fuse-ifelse.diff
(text/x-patch, 3.4 KB)
diff --git a/gcc/common/config/avr/avr-common.cc b/gcc/common/config/avr/avr-common.cc
index 8d1923a72bf..fb4f05553d7 100644
--- a/gcc/common/config/avr/avr-common.cc
+++ b/gcc/common/config/avr/avr-common.cc
@@ -44,6 +44,7 @@ static const struct default_options avr_option_optimization_table[] =
{ OPT_LEVELS_1_PLUS, OPT_mmain_is_OS_task, NULL, 1 },
{ OPT_LEVELS_1_PLUS, OPT_mfuse_add_, NULL, 1 },
{ OPT_LEVELS_2_PLUS, OPT_mfuse_add_, NULL, 2 },
+ { OPT_LEVELS_1_PLUS, OPT_mfuse_ifelse, NULL, 1 },
{ OPT_LEVELS_1_PLUS, OPT_mfuse_move2, NULL, 1 },
{ OPT_LEVELS_1_PLUS_NOT_DEBUG, OPT_mfuse_move_, NULL, 3 },
{ OPT_LEVELS_2_PLUS, OPT_mfuse_move_, NULL, 23 },
diff --git a/gcc/config/avr/avr-passes.cc b/gcc/config/avr/avr-passes.cc
index 7dc6f2b77c1..9df3c0e945c 100644
--- a/gcc/config/avr/avr-passes.cc
+++ b/gcc/config/avr/avr-passes.cc
@@ -3324,7 +3324,7 @@ public:
bool gate (function *) final override
{
- return optimize > 0;
+ return optimize > 0 && avropt_fuse_ifelse;
}
unsigned int execute (function *func) final override;
diff --git a/gcc/config/avr/avr.opt b/gcc/config/avr/avr.opt
index d56061b50b6..9c4be3ba93e 100644
--- a/gcc/config/avr/avr.opt
+++ b/gcc/config/avr/avr.opt
@@ -164,6 +164,10 @@ mfract-convert-truncate
Target Mask(FRACT_CONV_TRUNC)
Allow to use truncation instead of rounding towards zero for fractional fixed-point types.
+mfuse-ifelse
+Target Var(avropt_fuse_ifelse) Init(0) Optimization
+Optimize compare-branch-compare-branch sequences to compare-branch-branch.
+
mfuse-move
Target Alias(mfuse-move=, 23, 0) Optimization
Optimization. Run a post-reload pass that tweaks move instructions.
diff --git a/gcc/config/avr/avr.opt.urls b/gcc/config/avr/avr.opt.urls
index 004f9c45175..9988336cd49 100644
--- a/gcc/config/avr/avr.opt.urls
+++ b/gcc/config/avr/avr.opt.urls
@@ -99,6 +99,9 @@ UrlSuffix(gcc/AVR-Options.html#index-mfract-convert-truncate)
mfuse-move
UrlSuffix(gcc/AVR-Options.html#index-mfuse-move)
+mfuse-ifelse
+UrlSuffix(gcc/AVR-Options.html#index-mfuse-ifelse)
+
mfuse-move=
UrlSuffix(gcc/AVR-Options.html#index-mfuse-move)
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 01925ecf30d..e7a5bfbf1e9 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -986,8 +986,9 @@ Objective-C and Objective-C++ Dialects}.
@emph{AVR Options} (@ref{AVR Options})
@gccoptlist{-mmcu=@var{mcu} -mabsdata -maccumulate-args -masm-len-notes
--mcvt -mbranch-cost=@var{cost} -mfuse-add=@var{level} -mfuse-move=@var{level}
--mfuse-move2 -mcall-prologues -mgas-isr-prologues -mint8 -mflmap
+-mcvt -mbranch-cost=@var{cost} -mfuse-add=@var{level} -mfuse-ifelse
+-mfuse-move=@var{level} -mfuse-move2
+-mcall-prologues -mgas-isr-prologues -mint8 -mflmap
-mdouble=@var{bits} -mlong-double=@var{bits} -mno-call-main
-mn_flash=@var{size} -mfract-convert-truncate -mno-interrupts
-mmain-is-OS_task -mrelax -mpmem-wrap-around
@@ -24596,6 +24597,12 @@ The default uses @code{@var{level}=1} for optimizations @option{-Og}
and @option{-O1}, and @code{@var{level}=2} for higher optimizations.
Valid values for @var{level} are @code{0}, @code{1} and @code{2}.
+@opindex mfuse-ifelse
+@item -mfuse-ifelse
+Optimize compare-branch-compare-branch sequences to compare-branch-branch,
+which typically occurs in if-else trees generated from dense switch statements.
+This option is enabled per default if optimization is on.
+
@opindex mfuse-move
@item -mfuse-move
@itemx -mno-fuse-move