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@@ -207,9 +207,9 @@ choice
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config BR2_DEBUG_1
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bool "debug level 1"
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help
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- Debug level 1 produces minimal information, enough
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- for making backtraces in parts of the program that
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- you don't plan to debug. This includes descriptions
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+ Debug level 1 produces minimal information, enough
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+ for making backtraces in parts of the program that
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+ you don't plan to debug. This includes descriptions
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of functions and external variables, but no information
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about local variables and no line numbers.
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@@ -221,7 +221,7 @@ config BR2_DEBUG_2
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config BR2_DEBUG_3
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bool "debug level 3"
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help
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- Level 3 includes extra information, such as all the
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+ Level 3 includes extra information, such as all the
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macro definitions present in the program. Some debuggers
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support macro expansion when you use -g3.
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endchoice
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@@ -266,41 +266,41 @@ config BR2_OPTIMIZE_0
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bool "optimization level 0"
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depends on !BR2_PACKAGE_LINUX
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help
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- Do not optimize. This is the default.
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+ Do not optimize. This is the default.
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config BR2_OPTIMIZE_1
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bool "optimization level 1"
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depends on !BR2_PACKAGE_LINUX
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help
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- Optimize. Optimizing compilation takes somewhat more time,
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- and a lot more memory for a large function. With -O, the
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- compiler tries to reduce code size and execution time,
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- without performing any optimizations that take a great deal
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- of compilation time. -O turns on the following optimization
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- flags: -fdefer-pop -fdelayed-branch -fguess-branch-probability
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- -fcprop-registers -floop-optimize -fif-conversion
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- -fif-conversion2 -ftree-ccp -ftree-dce -ftree-dominator-opts
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- -ftree-dse -ftree-ter -ftree-lrs -ftree-sra -ftree-copyrename
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+ Optimize. Optimizing compilation takes somewhat more time,
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+ and a lot more memory for a large function. With -O, the
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+ compiler tries to reduce code size and execution time,
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+ without performing any optimizations that take a great deal
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+ of compilation time. -O turns on the following optimization
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+ flags: -fdefer-pop -fdelayed-branch -fguess-branch-probability
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+ -fcprop-registers -floop-optimize -fif-conversion
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+ -fif-conversion2 -ftree-ccp -ftree-dce -ftree-dominator-opts
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+ -ftree-dse -ftree-ter -ftree-lrs -ftree-sra -ftree-copyrename
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-ftree-fre -ftree-ch -funit-at-a-time -fmerge-constants
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- -O also turns on -fomit-frame-pointer on machines where doing
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+ -O also turns on -fomit-frame-pointer on machines where doing
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so does not interfere with debugging.
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config BR2_OPTIMIZE_2
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bool "optimization level 2"
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help
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Optimize even more. GCC performs nearly all supported optimizations
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- that do not involve a space-speed tradeoff. The compiler does not
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- perform loop unrolling or function inlining when you specify -O2.
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- As compared to -O, this option increases both compilation time and
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- the performance of the generated code. -O2 turns on all optimization
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- flags specified by -O. It also turns on the following optimization
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- flags: -fthread-jumps -fcrossjumping -foptimize-sibling-calls
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- -fcse-follow-jumps -fcse-skip-blocks -fgcse -fgcse-lm
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- -fexpensive-optimizations -fstrength-reduce -frerun-cse-after-loop
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- -frerun-loop-opt -fcaller-saves -fpeephole2 -fschedule-insns
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- -fschedule-insns2 -fsched-interblock -fsched-spec -fregmove
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- -fstrict-aliasing -fdelete-null-pointer-checks -freorder-blocks
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- -freorder-functions -falign-functions -falign-jumps -falign-loops
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+ that do not involve a space-speed tradeoff. The compiler does not
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+ perform loop unrolling or function inlining when you specify -O2.
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+ As compared to -O, this option increases both compilation time and
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+ the performance of the generated code. -O2 turns on all optimization
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+ flags specified by -O. It also turns on the following optimization
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+ flags: -fthread-jumps -fcrossjumping -foptimize-sibling-calls
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+ -fcse-follow-jumps -fcse-skip-blocks -fgcse -fgcse-lm
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+ -fexpensive-optimizations -fstrength-reduce -frerun-cse-after-loop
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+ -frerun-loop-opt -fcaller-saves -fpeephole2 -fschedule-insns
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+ -fschedule-insns2 -fsched-interblock -fsched-spec -fregmove
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+ -fstrict-aliasing -fdelete-null-pointer-checks -freorder-blocks
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+ -freorder-functions -falign-functions -falign-jumps -falign-loops
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-falign-labels -ftree-vrp -ftree-pre
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Please note the warning under -fgcse about invoking -O2 on programs
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that use computed gotos.
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@@ -308,20 +308,20 @@ config BR2_OPTIMIZE_2
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config BR2_OPTIMIZE_3
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bool "optimization level 3"
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help
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- Optimize yet more. -O3 turns on all optimizations specified by -O2
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- and also turns on the -finline-functions, -funswitch-loops and
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+ Optimize yet more. -O3 turns on all optimizations specified by -O2
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+ and also turns on the -finline-functions, -funswitch-loops and
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-fgcse-after-reload options.
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config BR2_OPTIMIZE_S
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bool "optimize for size"
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help
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- Optimize for size. -Os enables all -O2 optimizations that do not
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+ Optimize for size. -Os enables all -O2 optimizations that do not
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typically increase code size. It also performs further optimizations
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- designed to reduce code size. -Os disables the following optimization
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- flags: -falign-functions -falign-jumps -falign-loops -falign-labels
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+ designed to reduce code size. -Os disables the following optimization
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+ flags: -falign-functions -falign-jumps -falign-loops -falign-labels
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-freorder-blocks -freorder-blocks-and-partition -fprefetch-loop-arrays
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-ftree-vect-loop-version
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-
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+
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endchoice
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config BR2_PREFER_STATIC_LIB
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