mjit_compile.c: reduce sp motion on JIT

This retries r62655, which was reverted at r63863 for r63763.

tool/ruby_vm/views/_mjit_compile_insn.erb: revert the revert.
tool/ruby_vm/views/_mjit_compile_insn_body.erb: ditto.
tool/ruby_vm/views/_mjit_compile_pc_and_sp.erb: ditto.
tool/ruby_vm/views/_mjit_compile_send.erb: ditto.
tool/ruby_vm/views/mjit_compile.inc.erb: ditto.

tool/ruby_vm/views/_insn_entry.erb: revert half of r63763. The commit
  was originally reverted since changing pc motion was bad for tracing,
  but changing sp motion was totally fine. For JIT, I wanna resurrect
  the sp motion change in r62051.
tool/ruby_vm/models/bare_instructions.rb: ditto.
insns.def: ditto.
vm_insnhelper.c: ditto.
vm_insnhelper.h: ditto.

* benchmark

$ benchmark-driver benchmark.yml --rbenv 'before;after;before --jit;after --jit' --repeat-count 12 -v
before: ruby 2.6.0dev (2018-07-19 trunk 63998) [x86_64-linux]
after: ruby 2.6.0dev (2018-07-19 add-sp 63998) [x86_64-linux]
last_commit=mjit_compile.c: reduce sp motion on JIT
before --jit: ruby 2.6.0dev (2018-07-19 trunk 63998) +JIT [x86_64-linux]
after --jit: ruby 2.6.0dev (2018-07-19 add-sp 63998) +JIT [x86_64-linux]
last_commit=mjit_compile.c: reduce sp motion on JIT
Calculating -------------------------------------
                             before       after  before --jit  after --jit
Optcarrot Lan_Master.nes     51.354      50.238        70.010       72.139 fps

Comparison:
             Optcarrot Lan_Master.nes
             after --jit:        72.1 fps
            before --jit:        70.0 fps - 1.03x  slower
                  before:        51.4 fps - 1.40x  slower
                   after:        50.2 fps - 1.44x  slower

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@63999 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

7 files changed, 77 insertions, 5 deletions

diff --git a/tool/ruby_vm/models/bare_instructions.rb b/tool/ruby_vm/models/bare_instructions.rb
index 297a93f5b2..7e573240b5 100755
--- a/tool/ruby_vm/models/bare_instructions.rb
+++ b/tool/ruby_vm/models/bare_instructions.rb
@@ -101,6 +101,10 @@ class RubyVM::BareInstructions
     }.join
   end
 
+  def handles_frame?
+    /\b(false|0)\b/ !~ @attrs['handles_frame'].expr.expr
+  end
+
   def inspect
     sprintf "#<%s %s@%s:%d>", self.class.name, @name, @loc[0], @loc[1]
   end
@@ -125,6 +129,7 @@ class RubyVM::BareInstructions
     generate_attribute 'rb_num_t', 'retn', rets.size
     generate_attribute 'rb_num_t', 'width', width
     generate_attribute 'rb_snum_t', 'sp_inc', rets.size - pops.size
+    generate_attribute 'bool', 'handles_frame', false
   end
 
   def typesplit a
diff --git a/tool/ruby_vm/views/_insn_entry.erb b/tool/ruby_vm/views/_insn_entry.erb
index 836ca32b6b..bae8eae890 100644
--- a/tool/ruby_vm/views/_insn_entry.erb
+++ b/tool/ruby_vm/views/_insn_entry.erb
@@ -30,16 +30,25 @@ INSN_ENTRY(<%= insn.name %>)
 % end
     DEBUG_ENTER_INSN(INSN_ATTR(name));
     ADD_PC(INSN_ATTR(width));
+% if insn.handles_frame?
     POPN(INSN_ATTR(popn));
+% end
     COLLECT_USAGE_INSN(INSN_ATTR(bin));
 % insn.opes.each_with_index do |ope, i|
     COLLECT_USAGE_OPERAND(INSN_ATTR(bin), <%= i %>, <%= ope[:name] %>);
 % end
 <%= render_c_expr insn.expr -%>
     CHECK_VM_STACK_OVERFLOW_FOR_INSN(VM_REG_CFP, INSN_ATTR(retn));
-%   insn.rets.each do |ret|
+% if insn.handles_frame?
+%   insn.rets.reverse_each do |ret|
     PUSH(<%= insn.cast_to_VALUE ret %>);
 %   end
+% else
+    ADJ_SP(INSN_ATTR(sp_inc));
+%   insn.rets.reverse_each.with_index do |ret, i|
+    TOPN(<%= i %>) = <%= insn.cast_to_VALUE ret %>;
+%   end
+% end
     END_INSN(<%= insn.name %>);
 #   undef INSN_ATTR
 #   undef NAME_OF_CURRENT_INSN
diff --git a/tool/ruby_vm/views/_mjit_compile_insn.erb b/tool/ruby_vm/views/_mjit_compile_insn.erb
index 90127aa330..e0955687cc 100644
--- a/tool/ruby_vm/views/_mjit_compile_insn.erb
+++ b/tool/ruby_vm/views/_mjit_compile_insn.erb
@@ -20,6 +20,11 @@
         MAYBE_UNUSED(<%= ope.fetch(:decl) %>) = (<%= ope.fetch(:type) %>)operands[<%= i %>];
 % end
 %
+% # JIT: Declare stack_size to be used in some macro of _mjit_compile_insn_body.erb
+        if (status->local_stack_p) {
+            fprintf(f, "    MAYBE_UNUSED(unsigned int) stack_size = %u;\n", b->stack_size);
+        }
+%
 % # JIT: Declare variables for operands, popped values and return values
 % insn.declarations.each do |decl|
         fprintf(f, "    <%= decl %>;\n");
diff --git a/tool/ruby_vm/views/_mjit_compile_insn_body.erb b/tool/ruby_vm/views/_mjit_compile_insn_body.erb
index 0fef07da25..38fd8a9368 100644
--- a/tool/ruby_vm/views/_mjit_compile_insn_body.erb
+++ b/tool/ruby_vm/views/_mjit_compile_insn_body.erb
@@ -69,9 +69,37 @@
 %     end
 %   when /\A\s+DISPATCH_ORIGINAL_INSN\([^)]+\);\s+\z/
 %     # For `opt_xxx`'s fallbacks.
+        if (status->local_stack_p) {
+            fprintf(f, "            reg_cfp->sp = (VALUE *)reg_cfp->bp + %d;\n", b->stack_size + 1);
+        }
         fprintf(f, "            reg_cfp->pc = original_body_iseq + %d;\n", pos);
         fprintf(f, "            goto cancel;\n");
 %   else
+%     if insn.handles_frame?
+%       # If insn.handles_frame? is true, cfp->sp might be changed inside insns (like vm_caller_setup_arg_block)
+%       # and thus we need to use cfp->sp, even when local_stack_p is TRUE. When insn.handles_frame? is true,
+%       # cfp->sp should be available too because _mjit_compile_pc_and_sp.erb sets it.
+        fprintf(f, <%= to_cstr.call(line) %>);
+%     else
+%       # If local_stack_p is TRUE and insn.handles_frame? is false, stack values are only available in local variables
+%       # for stack. So we need to replace those macros if local_stack_p is TRUE here.
+%       case line
+%       when /\bGET_SP\(\)/
+%         # reg_cfp->sp
+        fprintf(f, <%= to_cstr.call(line.sub(/\bGET_SP\(\)/, '%s')) %>, (status->local_stack_p ? "(stack + stack_size)" : "GET_SP()"));
+%       when /\bSTACK_ADDR_FROM_TOP\((?<num>[^)]+)\)/
+%         # #define STACK_ADDR_FROM_TOP(n) (GET_SP()-(n))
+%         num = Regexp.last_match[:num]
+        fprintf(f, <%= to_cstr.call(line.sub(/\bSTACK_ADDR_FROM_TOP\(([^)]+)\)/, '%s')) %>,
+                (status->local_stack_p ? "stack + (stack_size - (<%= num %>))" : "STACK_ADDR_FROM_TOP(<%= num %>)"));
+%       when /\bTOPN\((?<num>[^)]+)\)/
+%         # #define TOPN(n) (*(GET_SP()-(n)-1))
+%         num = Regexp.last_match[:num]
+        fprintf(f, <%= to_cstr.call(line.sub(/\bTOPN\(([^)]+)\)/, '%s')) %>,
+              (status->local_stack_p ? "*(stack + (stack_size - (<%= num %>) - 1))" : "TOPN(<%= num %>)"));
+%       else
         fprintf(f, <%= to_cstr.call(line) %>);
+%       end
+%     end
 %   end
 % end
diff --git a/tool/ruby_vm/views/_mjit_compile_pc_and_sp.erb b/tool/ruby_vm/views/_mjit_compile_pc_and_sp.erb
index 6004504c06..da1465a685 100644
--- a/tool/ruby_vm/views/_mjit_compile_pc_and_sp.erb
+++ b/tool/ruby_vm/views/_mjit_compile_pc_and_sp.erb
@@ -12,4 +12,25 @@
         }
 %
 % # JIT: move sp to use or preserve stack variables
-        fprintf(f, "    reg_cfp->sp = (VALUE *)reg_cfp->bp + %d;\n", b->stack_size + 1 - <%= insn.pops.size %>); /* POPN(INSN_ATTR(popn)); */
+        if (status->local_stack_p) {
+% # sp motion is optimized away for `handles_frame? #=> false` case.
+% # Thus sp should be set properly before `goto cancel`.
+% if insn.handles_frame?
+%           # JIT-only behavior (pushing JIT's local variables to VM's stack):
+            {
+                rb_snum_t i, push_size;
+                push_size = -<%= insn.call_attribute('sp_inc') %> + <%= insn.rets.size %> - <%= insn.pops.size %>;
+                fprintf(f, "    reg_cfp->sp = (VALUE *)reg_cfp->bp + %ld + 1;\n", push_size); /* POPN(INSN_ATTR(popn)); */
+                for (i = 0; i < push_size; i++) { /* TODO: use memcpy? */
+                    fprintf(f, "    *(reg_cfp->sp + %ld) = stack[%ld];\n", i - push_size, (rb_snum_t)b->stack_size - push_size + i);
+                }
+            }
+% end
+        }
+        else {
+% if insn.handles_frame?
+            fprintf(f, "    reg_cfp->sp = (VALUE *)reg_cfp->bp + %d;\n", b->stack_size + 1 - <%= insn.pops.size %>); /* POPN(INSN_ATTR(popn)); */
+% else
+            fprintf(f, "    reg_cfp->sp = (VALUE *)reg_cfp->bp + %d;\n", b->stack_size + 1);
+% end
+        }
diff --git a/tool/ruby_vm/views/_mjit_compile_send.erb b/tool/ruby_vm/views/_mjit_compile_send.erb
index 6944903821..0a01ea2f86 100644
--- a/tool/ruby_vm/views/_mjit_compile_send.erb
+++ b/tool/ruby_vm/views/_mjit_compile_send.erb
@@ -24,6 +24,10 @@
             int param_size = iseq->body->param.size; /* TODO: check calling->argc for argument_arity_error */
 
             fprintf(f, "{\n");
+% # JIT: Declare stack_size to be used in some macro of _mjit_compile_insn_body.erb
+            if (status->local_stack_p) {
+                fprintf(f, "    MAYBE_UNUSED(unsigned int) stack_size = %u;\n", b->stack_size);
+            }
 
 % # JIT: Invalidate call cache if it requires vm_search_method. This allows to inline some of following things.
 <%= render 'mjit_compile_send_guard' -%>
diff --git a/tool/ruby_vm/views/mjit_compile.inc.erb b/tool/ruby_vm/views/mjit_compile.inc.erb
index 7749984c36..ee29693894 100644
--- a/tool/ruby_vm/views/mjit_compile.inc.erb
+++ b/tool/ruby_vm/views/mjit_compile.inc.erb
@@ -31,13 +31,13 @@
 % #   reg_cfp: the second argument of _mjitXXX
 % #   GET_CFP(): refers to `reg_cfp`
 % #   GET_EP(): refers to `reg_cfp->ep`
-% #   GET_SP(): refers to `reg_cfp->sp`
+% #   GET_SP(): refers to `reg_cfp->sp`, or `(stack + stack_size)` if local_stack_p
 % #   GET_SELF(): refers to `reg_cfp->self`
 % #   GET_LEP(): refers to `VM_EP_LEP(reg_cfp->ep)`
 % #   EXEC_EC_CFP(): refers to `val = vm_exec(ec, TRUE)` with frame setup
 % #   CALL_METHOD(): using `GET_CFP()` and `EXEC_EC_CFP()`
-% #   TOPN(): refers to `reg_cfp->sp`
-% #   STACK_ADDR_FROM_TOP(): refers to `reg_cfp->sp`
+% #   TOPN(): refers to `reg_cfp->sp`, or `*(stack + (stack_size - num - 1))` if local_stack_p
+% #   STACK_ADDR_FROM_TOP(): refers to `reg_cfp->sp`, or `stack + (stack_size - num)` if local_stack_p
 % #   DISPATCH_ORIGINAL_INSN(): expanded in _mjit_compile_insn.erb
 % #   THROW_EXCEPTION(): specially defined for JIT
 % #   RESTORE_REGS(): specially defined for `leave`