On 1/20/21 10:50 AM, Jonathan Wakely wrote:
That's a different situation though. With -O0 **NO** optimization is done,
at all. Any -f options for optimization passes are ignored entirely.
The difference between -O1 and -O2 is the set of -f flags that differ, and
some specific checks for >= -O2. But the difference between -O0 and -O1 is
the difference between zero and non-zero. Completely off, or on.
That's interesting, Jonathan. You know far better than I do, and I
haven't tried it in over a year (on an older version of GCC-ARM), but I
swore the following did do something:
OPTIMIZE_FLAG := -O0 \
-fbranch-count-reg \
-fcombine-stack-adjustments \
-fcompare-elim \
-fcprop-registers \
-fdefer-pop \
-fforward-propagate \
-fguess-branch-probability \
-fif-conversion \
-fif-conversion2 \
-finline \
-finline-functions-called-once \
-fipa-profile \
-fipa-pure-const \
-fipa-reference \
-fmerge-constants \
-fmove-loop-invariants \
-fomit-frame-pointer \
-freorder-blocks \
-fsched-pressure \
-fsection-anchors \
-fshrink-wrap \
-fsplit-wide-types \
-fssa-phiopt \
-ftoplevel-reorder \
-ftree-bit-ccp \
-ftree-builtin-call-dce \
-ftree-ccp \
-ftree-ch \
-ftree-coalesce-vars \
-ftree-copy-prop \
-ftree-dce \
-ftree-dominator-opts \
-ftree-dse \
-ftree-fre \
-ftree-pta \
-ftree-sink \
-ftree-slsr \
-ftree-sra \
-ftree-ter \
-fvar-tracking \
-fvar-tracking-assignments
Maybe because you said "optimization passes"? The ones above (or some of
them) are for other passes?
--
MARK
markrubn@xxxxxxxxx
