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| author | Björn Gustavsson <[email protected]> | 2015-01-23 13:12:44 +0100 |
|---|---|---|
| committer | Björn Gustavsson <[email protected]> | 2015-02-03 08:40:49 +0100 |
| commit | cd1eaf0116190ab72f3a792b74be99eda5dd31eb (patch) | |
| tree | 0d036a4c6d102d1bd5859c894dd163b6a0a8f0ad /lib/compiler/test/trycatch_SUITE.erl | |
| parent | 8c3baeb1275c2e6a316d3b5203e0598906785cdb (diff) | |
| download | otp-cd1eaf0116190ab72f3a792b74be99eda5dd31eb.tar.gz otp-cd1eaf0116190ab72f3a792b74be99eda5dd31eb.tar.bz2 otp-cd1eaf0116190ab72f3a792b74be99eda5dd31eb.zip | |
sys_core_fold: Optimize let statements more aggressively
I originally decided that in 'value' context, rewriting a let statement
where the variables were not in the body to a sequence was not worth
it, because the variables would be unused in only one let in a
thousand lets (roughly).
I have reconsidered.
The main reason is that if we do the rewrite, core_lib:is_var_used/2
will be used much more frequently, which will help us to find bugs
in it sooner.
Another reason is that the way letify/2 is currently implemented
with its own calls to core_lib:is_var_used/2 is only safe as long
as all the bindings are independent of each other. We could make
letify/2 smarter, but if we introduce this new optimization there
is no need.
Measuring compilation speed, I have not seen any significant slowdown.
It seems that although core_lib:is_var_used/2 is called much more
frequently, most calls will be fast because is_var_used/2 will quickly
find a use of the variable.
Also add a test case to cover a line opt_guard_try/1 that was
no longer covered.
Diffstat (limited to 'lib/compiler/test/trycatch_SUITE.erl')
| -rw-r--r-- | lib/compiler/test/trycatch_SUITE.erl | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/lib/compiler/test/trycatch_SUITE.erl b/lib/compiler/test/trycatch_SUITE.erl index b490257a6e..8ab618bb01 100644 --- a/lib/compiler/test/trycatch_SUITE.erl +++ b/lib/compiler/test/trycatch_SUITE.erl @@ -790,7 +790,6 @@ nested_after_1({X1,C1,V1}, nested_horrid(Config) when is_list(Config) -> - _V = {make_ref(),nested_horrid,4.711}, {[true,true],{[true,1.0],1.0}} = nested_horrid_1({true,void,void}, 1.0), ok. |