Clean up OPT_STACK_CACHING (#8132)

16 files changed, 5 insertions, 265 deletions

diff --git a/common.mk b/common.mk
index ffe04bd6af..0b348bf52d 100644
--- a/common.mk
+++ b/common.mk
@@ -1070,7 +1070,7 @@ parse.$(OBJEXT): {$(VPATH)}parse.c
 miniprelude.$(OBJEXT): {$(VPATH)}miniprelude.c
 
 # dependencies for optional sources.
-compile.$(OBJEXT): {$(VPATH)}opt_sc.inc {$(VPATH)}optunifs.inc
+compile.$(OBJEXT): {$(VPATH)}optunifs.inc
 
 win32/win32.$(OBJEXT): {$(VPATH)}win32/win32.c {$(VPATH)}win32/file.h \
   {$(VPATH)}dln.h {$(VPATH)}dln_find.c {$(VPATH)}encindex.h \
@@ -1097,7 +1097,6 @@ INSNS2VMOPT = --srcdir="$(srcdir)"
 srcs_vpath = {$(VPATH)}
 
 inc_common_headers = $(tooldir)/ruby_vm/views/_copyright.erb $(tooldir)/ruby_vm/views/_notice.erb
-$(srcs_vpath)opt_sc.inc: $(tooldir)/ruby_vm/views/opt_sc.inc.erb $(inc_common_headers)
 $(srcs_vpath)optinsn.inc: $(tooldir)/ruby_vm/views/optinsn.inc.erb $(inc_common_headers)
 $(srcs_vpath)optunifs.inc: $(tooldir)/ruby_vm/views/optunifs.inc.erb $(inc_common_headers)
 $(srcs_vpath)insns.inc: $(tooldir)/ruby_vm/views/insns.inc.erb $(inc_common_headers)
diff --git a/compile.c b/compile.c
index 99172fe391..33c3de2617 100644
--- a/compile.c
+++ b/compile.c
@@ -486,7 +486,6 @@ static int iseq_set_local_table(rb_iseq_t *iseq, const rb_ast_id_table_t *tbl);
 static int iseq_set_exception_local_table(rb_iseq_t *iseq);
 static int iseq_set_arguments(rb_iseq_t *iseq, LINK_ANCHOR *const anchor, const NODE *const node);
 
-static int iseq_set_sequence_stackcaching(rb_iseq_t *iseq, LINK_ANCHOR *const anchor);
 static int iseq_set_sequence(rb_iseq_t *iseq, LINK_ANCHOR *const anchor);
 static int iseq_set_exception_table(rb_iseq_t *iseq);
 static int iseq_set_optargs_table(rb_iseq_t *iseq);
@@ -1465,13 +1464,6 @@ iseq_setup_insn(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
             dump_disasm_list(FIRST_ELEMENT(anchor));
     }
 
-    if (ISEQ_COMPILE_DATA(iseq)->option->stack_caching) {
-        debugs("[compile step 3.3 (iseq_set_sequence_stackcaching)]\n");
-        iseq_set_sequence_stackcaching(iseq, anchor);
-        if (compile_debug > 5)
-            dump_disasm_list(FIRST_ELEMENT(anchor));
-    }
-
     debugs("[compile step 3.4 (iseq_insert_nop_between_end_and_cont)]\n");
     iseq_insert_nop_between_end_and_cont(iseq);
     if (compile_debug > 5)
@@ -3952,167 +3944,6 @@ iseq_insns_unification(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
     return COMPILE_OK;
 }
 
-#if OPT_STACK_CACHING
-
-#define SC_INSN(insn, stat) sc_insn_info[(insn)][(stat)]
-#define SC_NEXT(insn)       sc_insn_next[(insn)]
-
-#include "opt_sc.inc"
-
-static int
-insn_set_sc_state(rb_iseq_t *iseq, const LINK_ELEMENT *anchor, INSN *iobj, int state)
-{
-    int nstate;
-    int insn_id;
-
-    insn_id = iobj->insn_id;
-    iobj->insn_id = SC_INSN(insn_id, state);
-    nstate = SC_NEXT(iobj->insn_id);
-
-    if (insn_id == BIN(jump) ||
-        insn_id == BIN(branchif) || insn_id == BIN(branchunless)) {
-        LABEL *lobj = (LABEL *)OPERAND_AT(iobj, 0);
-
-        if (lobj->sc_state != 0) {
-            if (lobj->sc_state != nstate) {
-                BADINSN_DUMP(anchor, iobj, lobj);
-                COMPILE_ERROR(iseq, iobj->insn_info.line_no,
-                              "insn_set_sc_state error: %d at "LABEL_FORMAT
-                              ", %d expected\n",
-                              lobj->sc_state, lobj->label_no, nstate);
-                return COMPILE_NG;
-            }
-        }
-        else {
-            lobj->sc_state = nstate;
-        }
-        if (insn_id == BIN(jump)) {
-            nstate = SCS_XX;
-        }
-    }
-    else if (insn_id == BIN(leave)) {
-        nstate = SCS_XX;
-    }
-
-    return nstate;
-}
-
-static int
-label_set_sc_state(LABEL *lobj, int state)
-{
-    if (lobj->sc_state != 0) {
-        if (lobj->sc_state != state) {
-            state = lobj->sc_state;
-        }
-    }
-    else {
-        lobj->sc_state = state;
-    }
-
-    return state;
-}
-
-
-#endif
-
-static int
-iseq_set_sequence_stackcaching(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
-{
-#if OPT_STACK_CACHING
-    LINK_ELEMENT *list;
-    int state, insn_id;
-
-    /* initialize */
-    state = SCS_XX;
-    list = FIRST_ELEMENT(anchor);
-    /* dump_disasm_list(list); */
-
-    /* for each list element */
-    while (list) {
-      redo_point:
-        switch (list->type) {
-          case ISEQ_ELEMENT_INSN:
-            {
-                INSN *iobj = (INSN *)list;
-                insn_id = iobj->insn_id;
-
-                /* dump_disasm_list(list); */
-
-                switch (insn_id) {
-                  case BIN(nop):
-                    {
-                        /* exception merge point */
-                        if (state != SCS_AX) {
-                            NODE dummy_line_node = generate_dummy_line_node(0, -1);
-                            INSN *rpobj =
-                                new_insn_body(iseq, &dummy_line_node, BIN(reput), 0);
-
-                            /* replace this insn */
-                            ELEM_REPLACE(list, (LINK_ELEMENT *)rpobj);
-                            list = (LINK_ELEMENT *)rpobj;
-                            goto redo_point;
-                        }
-                        break;
-                    }
-                  case BIN(swap):
-                    {
-                        if (state == SCS_AB || state == SCS_BA) {
-                            state = (state == SCS_AB ? SCS_BA : SCS_AB);
-
-                            ELEM_REMOVE(list);
-                            list = list->next;
-                            goto redo_point;
-                        }
-                        break;
-                    }
-                  case BIN(pop):
-                    {
-                        switch (state) {
-                          case SCS_AX:
-                          case SCS_BX:
-                            state = SCS_XX;
-                            break;
-                          case SCS_AB:
-                            state = SCS_AX;
-                            break;
-                          case SCS_BA:
-                            state = SCS_BX;
-                            break;
-                          case SCS_XX:
-                            goto normal_insn;
-                          default:
-                            COMPILE_ERROR(iseq, iobj->insn_info.line_no,
-                                          "unreachable");
-                            return COMPILE_NG;
-                        }
-                        /* remove useless pop */
-                        ELEM_REMOVE(list);
-                        list = list->next;
-                        goto redo_point;
-                    }
-                  default:;
-                    /* none */
-                }		/* end of switch */
-              normal_insn:
-                state = insn_set_sc_state(iseq, anchor, iobj, state);
-                break;
-            }
-          case ISEQ_ELEMENT_LABEL:
-            {
-                LABEL *lobj;
-                lobj = (LABEL *)list;
-
-                state = label_set_sc_state(lobj, state);
-            }
-          default:
-            break;
-        }
-        list = list->next;
-    }
-#endif
-    return COMPILE_OK;
-}
-
 static int
 all_string_result_p(const NODE *node)
 {
diff --git a/iseq.c b/iseq.c
index c1dd3efc4c..540f180e2e 100644
--- a/iseq.c
+++ b/iseq.c
@@ -706,7 +706,6 @@ static rb_compile_option_t COMPILE_OPTION_DEFAULT = {
     OPT_SPECIALISED_INSTRUCTION, /* int specialized_instruction; */
     OPT_OPERANDS_UNIFICATION, /* int operands_unification; */
     OPT_INSTRUCTIONS_UNIFICATION, /* int instructions_unification; */
-    OPT_STACK_CACHING, /* int stack_caching; */
     OPT_FROZEN_STRING_LITERAL,
     OPT_DEBUG_FROZEN_STRING_LITERAL,
     TRUE,			/* coverage_enabled */
@@ -732,7 +731,6 @@ set_compile_option_from_hash(rb_compile_option_t *option, VALUE opt)
     SET_COMPILE_OPTION(option, opt, specialized_instruction);
     SET_COMPILE_OPTION(option, opt, operands_unification);
     SET_COMPILE_OPTION(option, opt, instructions_unification);
-    SET_COMPILE_OPTION(option, opt, stack_caching);
     SET_COMPILE_OPTION(option, opt, frozen_string_literal);
     SET_COMPILE_OPTION(option, opt, debug_frozen_string_literal);
     SET_COMPILE_OPTION(option, opt, coverage_enabled);
@@ -795,7 +793,6 @@ make_compile_option_value(rb_compile_option_t *option)
         SET_COMPILE_OPTION(option, opt, specialized_instruction);
         SET_COMPILE_OPTION(option, opt, operands_unification);
         SET_COMPILE_OPTION(option, opt, instructions_unification);
-        SET_COMPILE_OPTION(option, opt, stack_caching);
         SET_COMPILE_OPTION(option, opt, frozen_string_literal);
         SET_COMPILE_OPTION(option, opt, debug_frozen_string_literal);
         SET_COMPILE_OPTION(option, opt, coverage_enabled);
@@ -1431,7 +1428,6 @@ iseqw_s_compile_file(int argc, VALUE *argv, VALUE self)
  *  * +:operands_unification+
  *  * +:peephole_optimization+
  *  * +:specialized_instruction+
- *  * +:stack_caching+
  *  * +:tailcall_optimization+
  *
  *  Additionally, +:debug_level+ can be set to an integer.
diff --git a/iseq.h b/iseq.h
index b12228eed9..42ddb05147 100644
--- a/iseq.h
+++ b/iseq.h
@@ -226,7 +226,6 @@ struct rb_compile_option_struct {
     unsigned int specialized_instruction: 1;
     unsigned int operands_unification: 1;
     unsigned int instructions_unification: 1;
-    unsigned int stack_caching: 1;
     unsigned int frozen_string_literal: 1;
     unsigned int debug_frozen_string_literal: 1;
     unsigned int coverage_enabled: 1;
diff --git a/mini_builtin.c b/mini_builtin.c
index 66d90eb83f..a0bb46c54c 100644
--- a/mini_builtin.c
+++ b/mini_builtin.c
@@ -35,7 +35,6 @@ builtin_iseq_load(const char *feature_name, const struct rb_builtin_function *ta
         TRUE, /* unsigned int specialized_instruction; */
         TRUE, /* unsigned int operands_unification; */
         TRUE, /* unsigned int instructions_unification; */
-        TRUE, /* unsigned int stack_caching; */
         TRUE, /* unsigned int frozen_string_literal; */
         FALSE, /* unsigned int debug_frozen_string_literal; */
         FALSE, /* unsigned int coverage_enabled; */
diff --git a/template/Makefile.in b/template/Makefile.in
index 7ca7e89032..1b490b23e9 100644
--- a/template/Makefile.in
+++ b/template/Makefile.in
@@ -580,7 +580,7 @@ update-known-errors:
 	errno --list | cut -d' ' -f1 | sort -u - $(srcdir)/defs/known_errors.def | \
 	$(IFCHANGE) $(srcdir)/defs/known_errors.def -
 
-INSNS	= opt_sc.inc optinsn.inc optunifs.inc insns.inc insns_info.inc \
+INSNS	= optinsn.inc optunifs.inc insns.inc insns_info.inc \
 	  vmtc.inc vm.inc
 
 $(INSNS): $(srcdir)/insns.def vm_opts.h \
@@ -620,7 +620,6 @@ $(INSNS): $(srcdir)/insns.def vm_opts.h \
 	  $(tooldir)/ruby_vm/views/_trace_instruction.erb \
 	  $(tooldir)/ruby_vm/views/insns.inc.erb \
 	  $(tooldir)/ruby_vm/views/insns_info.inc.erb \
-	  $(tooldir)/ruby_vm/views/opt_sc.inc.erb \
 	  $(tooldir)/ruby_vm/views/optinsn.inc.erb \
 	  $(tooldir)/ruby_vm/views/optunifs.inc.erb \
 	  $(tooldir)/ruby_vm/views/vm.inc.erb \
diff --git a/template/prelude.c.tmpl b/template/prelude.c.tmpl
index 7c2f8181a0..aa8b0c1fef 100644
--- a/template/prelude.c.tmpl
+++ b/template/prelude.c.tmpl
@@ -186,7 +186,6 @@ prelude_eval(VALUE code, VALUE name, int line)
         TRUE, /* unsigned int specialized_instruction; */
         TRUE, /* unsigned int operands_unification; */
         TRUE, /* unsigned int instructions_unification; */
-        TRUE, /* unsigned int stack_caching; */
         TRUE, /* unsigned int frozen_string_literal; */
         FALSE, /* unsigned int debug_frozen_string_literal; */
         FALSE, /* unsigned int coverage_enabled; */
diff --git a/tool/ruby_vm/views/opt_sc.inc.erb b/tool/ruby_vm/views/opt_sc.inc.erb
deleted file mode 100644
index e58c81989f..0000000000
--- a/tool/ruby_vm/views/opt_sc.inc.erb
+++ /dev/null
@@ -1,40 +0,0 @@
-/* -*- C -*- */
-
-%# Copyright (c) 2017 Urabe, Shyouhei.  All rights reserved.
-%#
-%# This file is a part of  the programming language Ruby.  Permission is hereby
-%# granted, to either  redistribute and/or modify this file,  provided that the
-%# conditions mentioned  in the  file COPYING  are met.   Consult the  file for
-%# details.
-% raise ':FIXME:TBW' if RubyVM::VmOptsH['STACK_CACHING']
-<%= render 'copyright' %>
-<%= render 'notice', locals: {
-    this_file: 'is for threaded code',
-    edit: __FILE__,
-} -%>
-
-#define SC_STATE_SIZE 6
-
-#define SCS_XX 1
-#define SCS_AX 2
-#define SCS_BX 3
-#define SCS_AB 4
-#define SCS_BA 5
-
-#define SC_ERROR 0xffffffff
-
-static const VALUE sc_insn_info[][SC_STATE_SIZE] = {
-#define NO_SC { SC_ERROR, SC_ERROR, SC_ERROR, SC_ERROR, SC_ERROR, SC_ERROR }
-% RubyVM::Instructions.each_slice 8 do |a|
-    <%= a.map{|i| 'NO_SC' }.join(', ') %>,
-% end
-#undef NO_SC
-};
-
-static const VALUE sc_insn_next[] = {
-% RubyVM::Instructions.each_slice 8 do |a|
-    <%= a.map{|i| 'SCS_XX' }.join(', ') %>,
-% end
-};
-
-ASSERT_VM_INSTRUCTION_SIZE(sc_insn_next);
diff --git a/tool/update-deps b/tool/update-deps
index c79a8a61c5..a367669435 100755
--- a/tool/update-deps
+++ b/tool/update-deps
@@ -122,7 +122,6 @@ FILES_NEED_VPATH = %w[
   miniprelude.c
   newline.c
   node_name.inc
-  opt_sc.inc
   optinsn.inc
   optunifs.inc
   parse.c
diff --git a/vm.c b/vm.c
index e55003af3d..cf412ddf30 100644
--- a/vm.c
+++ b/vm.c
@@ -2483,11 +2483,7 @@ vm_exec_handle_exception(rb_execution_context_t *ec, enum ruby_tag_type state,
                 }
                 else {
                     /* TAG_BREAK */
-#if OPT_STACK_CACHING
-                    *initial = THROW_DATA_VAL(err);
-#else
                     *ec->cfp->sp++ = THROW_DATA_VAL(err);
-#endif
                     ec->errinfo = Qnil;
                     return Qundef;
                 }
@@ -2560,11 +2556,7 @@ vm_exec_handle_exception(rb_execution_context_t *ec, enum ruby_tag_type state,
                         cfp->sp = vm_base_ptr(cfp) + entry->sp;
 
                         if (state != TAG_REDO) {
-#if OPT_STACK_CACHING
-                            *initial = THROW_DATA_VAL(err);
-#else
                             *ec->cfp->sp++ = THROW_DATA_VAL(err);
-#endif
                         }
                         ec->errinfo = Qnil;
                         VM_ASSERT(ec->tag->state == TAG_NONE);
@@ -3890,9 +3882,6 @@ Init_VM(void)
     rb_ary_push(opts, rb_str_new2("call threaded code"));
 #endif
 
-#if OPT_STACK_CACHING
-    rb_ary_push(opts, rb_str_new2("stack caching"));
-#endif
 #if OPT_OPERANDS_UNIFICATION
     rb_ary_push(opts, rb_str_new2("operands unification"));
 #endif
diff --git a/vm_core.h b/vm_core.h
index 4b321d123e..64ea673d77 100644
--- a/vm_core.h
+++ b/vm_core.h
@@ -182,9 +182,6 @@ void *rb_register_sigaltstack(void *);
 #if    OPT_DIRECT_THREADED_CODE
 #undef OPT_DIRECT_THREADED_CODE
 #endif /* OPT_DIRECT_THREADED_CODE */
-#if    OPT_STACK_CACHING
-#undef OPT_STACK_CACHING
-#endif /* OPT_STACK_CACHING */
 #endif /* OPT_CALL_THREADED_CODE */
 
 void rb_vm_encoded_insn_data_table_init(void);
@@ -1684,11 +1681,7 @@ VALUE rb_proc_dup(VALUE self);
 /* for debug */
 extern void rb_vmdebug_stack_dump_raw(const rb_execution_context_t *ec, const rb_control_frame_t *cfp);
 extern void rb_vmdebug_debug_print_pre(const rb_execution_context_t *ec, const rb_control_frame_t *cfp, const VALUE *_pc);
-extern void rb_vmdebug_debug_print_post(const rb_execution_context_t *ec, const rb_control_frame_t *cfp
-#if OPT_STACK_CACHING
-    , VALUE reg_a, VALUE reg_b
-#endif
-);
+extern void rb_vmdebug_debug_print_post(const rb_execution_context_t *ec, const rb_control_frame_t *cfp);
 
 #define SDR() rb_vmdebug_stack_dump_raw(GET_EC(), GET_EC()->cfp)
 #define SDR2(cfp) rb_vmdebug_stack_dump_raw(GET_EC(), (cfp))
diff --git a/vm_dump.c b/vm_dump.c
index ba5434b393..b9f4e098a0 100644
--- a/vm_dump.c
+++ b/vm_dump.c
@@ -422,11 +422,7 @@ rb_vmdebug_debug_print_pre(const rb_execution_context_t *ec, const rb_control_fr
 }
 
 void
-rb_vmdebug_debug_print_post(const rb_execution_context_t *ec, const rb_control_frame_t *cfp
-#if OPT_STACK_CACHING
-                 , VALUE reg_a, VALUE reg_b
-#endif
-    )
+rb_vmdebug_debug_print_post(const rb_execution_context_t *ec, const rb_control_frame_t *cfp)
 {
 #if VMDEBUG > 9
     SDR2(cfp);
@@ -442,15 +438,6 @@ rb_vmdebug_debug_print_post(const rb_execution_context_t *ec, const rb_control_f
     /* stack_dump_thobj(ec); */
     vm_stack_dump_each(ec, ec->cfp);
 
-#if OPT_STACK_CACHING
-    {
-        VALUE rstr;
-        rstr = rb_inspect(reg_a);
-        fprintf(stderr, "  sc reg A: %s\n", StringValueCStr(rstr));
-        rstr = rb_inspect(reg_b);
-        fprintf(stderr, "  sc reg B: %s\n", StringValueCStr(rstr));
-    }
-#endif
     printf
         ("--------------------------------------------------------------\n");
 #endif
diff --git a/vm_exec.c b/vm_exec.c
index 1a4e0ad514..0d892c7d7d 100644
--- a/vm_exec.c
+++ b/vm_exec.c
@@ -97,11 +97,6 @@ vm_exec_core(rb_execution_context_t *ec, VALUE initial)
     reg_cfp = ec->cfp;
     reg_pc = reg_cfp->pc;
 
-#if OPT_STACK_CACHING
-    reg_a = initial;
-    reg_b = 0;
-#endif
-
   first:
     INSN_DISPATCH();
 /*****************/
diff --git a/vm_exec.h b/vm_exec.h
index 41c4b74ffc..152410a6a7 100644
--- a/vm_exec.h
+++ b/vm_exec.h
@@ -21,11 +21,7 @@ typedef rb_iseq_t *ISEQ;
 #define DEBUG_ENTER_INSN(insn) \
     rb_vmdebug_debug_print_pre(ec, GET_CFP(), GET_PC());
 
-#if OPT_STACK_CACHING
-#define SC_REGS() , reg_a, reg_b
-#else
 #define SC_REGS()
-#endif
 
 #define DEBUG_END_INSN() \
   rb_vmdebug_debug_print_post(ec, GET_CFP() SC_REGS());
diff --git a/vm_opts.h b/vm_opts.h
index c9fb7433d6..7b3caf4754 100644
--- a/vm_opts.h
+++ b/vm_opts.h
@@ -54,7 +54,6 @@
 #define OPT_OPERANDS_UNIFICATION     1
 #define OPT_INSTRUCTIONS_UNIFICATION 0
 #define OPT_UNIFY_ALL_COMBINATION    0
-#define OPT_STACK_CACHING            0
 
 /* misc */
 #ifndef OPT_SUPPORT_JOKE
diff --git a/win32/Makefile.sub b/win32/Makefile.sub
index 9f03280fa2..e258e0388b 100644
--- a/win32/Makefile.sub
+++ b/win32/Makefile.sub
@@ -1365,7 +1365,7 @@ probes.h: {$(VPATH)}probes.dmyh
 #include "$(*F).dmyh"
 <<KEEP
 
-INSNS	= opt_sc.inc optinsn.inc optunifs.inc insns.inc insns_info.inc \
+INSNS	= optinsn.inc optunifs.inc insns.inc insns_info.inc \
 	  vmtc.inc vm.inc
 
 !if [exit > insns_rules.mk]