fix redefinition optimization for -"literal string" (UMinus)

Unfortunately this enlarges insns.def by yet another
instruction.  However, it is much prettier than opt_str_freeze
in use, and maybe we can avoid having so many instructions in
the future.

[ruby-core:80368]

* insns.def (DEFINE_INSN): new instruction: opt_str_uminus (maybe temporary)
* compile.c (iseq_compile_each0): split instructions
* test/ruby/test_optimization.rb (test_string_uminus): new test
* vm.c (vm_init_redefined_flag): set redefinintion flag for uminus
* vm_core.h (enum ruby_basic_operators): add BOP_UMINUS

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@58144 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 1 insertions, 0 deletions

diff --git a/vm.c b/vm.c
index 1eefee18a6..9ece1b8c3d 100644
--- a/vm.c
+++ b/vm.c
@@ -1569,6 +1569,7 @@ vm_init_redefined_flag(void)
     OP(Succ, SUCC), (C(Integer), C(String), C(Time));
     OP(EqTilde, MATCH), (C(Regexp), C(String));
     OP(Freeze, FREEZE), (C(String));
+    OP(UMinus, UMINUS), (C(String));
     OP(Max, MAX), (C(Array));
     OP(Min, MIN), (C(Array));
 #undef C