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authorBjörn Gustavsson <[email protected]>2018-01-25 10:09:59 +0100
committerBjörn Gustavsson <[email protected]>2018-01-26 15:57:57 +0100
commitfbcff5a137e37edd80aca9c5fe18ce6880648169 (patch)
treefb846d82599a3e52230f1b028b59f63cb0dd09ec /lib/compiler/src/compile.erl
parent5b58d9e2d3262160b7f10d8b6798f89f0618c5f6 (diff)
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Eliminate get_list/3 internally in the compiler
Instructions that produce more than one result complicate optimizations. get_list/3 is one of two instructions that produce multiple results (get_map_elements/3 is the other). Introduce the get_hd/2 and get_tl/2 instructions that return the head and tail of a cons cell, respectively, and use it internally in all optimization passes. For efficiency, we still want to use get_list/3 if both head and tail are used, so we will translate matching pairs of get_hd and get_tl back to get_list instructions.
Diffstat (limited to 'lib/compiler/src/compile.erl')
-rw-r--r--lib/compiler/src/compile.erl10
1 files changed, 6 insertions, 4 deletions
diff --git a/lib/compiler/src/compile.erl b/lib/compiler/src/compile.erl
index 1409c358c2..c6a0056a70 100644
--- a/lib/compiler/src/compile.erl
+++ b/lib/compiler/src/compile.erl
@@ -219,13 +219,15 @@ expand_opt(report, Os) ->
expand_opt(return, Os) ->
[return_errors,return_warnings|Os];
expand_opt(r16, Os) ->
- [no_record_opt,no_utf8_atoms|Os];
+ [no_get_hd_tl,no_record_opt,no_utf8_atoms|Os];
expand_opt(r17, Os) ->
- [no_record_opt,no_utf8_atoms|Os];
+ [no_get_hd_tl,no_record_opt,no_utf8_atoms|Os];
expand_opt(r18, Os) ->
- [no_record_opt,no_utf8_atoms|Os];
+ [no_get_hd_tl,no_record_opt,no_utf8_atoms|Os];
expand_opt(r19, Os) ->
- [no_record_opt,no_utf8_atoms|Os];
+ [no_get_hd_tl,no_record_opt,no_utf8_atoms|Os];
+expand_opt(r20, Os) ->
+ [no_get_hd_tl,no_record_opt,no_utf8_atoms|Os];
expand_opt({debug_info_key,_}=O, Os) ->
[encrypt_debug_info,O|Os];
expand_opt(no_float_opt, Os) ->