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Add control flow attribute to each opcode
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Required for Breakpoint to be able to determine how to step through
code.
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@agardiner
agardiner committed Dec 5, 2009
1 parent a9051ec commit da3d4f8
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Showing 4 changed files with 74 additions and 40 deletions.
4 changes: 3 additions & 1 deletion lib/compiler/iseq.rb
View file
Expand Up @@ -7,7 +7,7 @@ class InstructionSet
class OpCode
attr_reader :args, :arg_count, :bytecode, :opcode, :size,
:stack, :stack_consumed, :stack_produced, :variable_stack,
:position, :stack_difference
:position, :stack_difference, :control_flow

alias_method :name, :opcode
alias_method :width, :size
Expand All @@ -28,6 +28,8 @@ def initialize(opcode, bytecode, params)
extra, @position = @stack_consumed
@stack_difference = @stack_produced - extra
end

@control_flow = params[:control_flow]
end

def variable_stack?
Expand Down
25 changes: 21 additions & 4 deletions rakelib/instruction_parser.rb
View file
Expand Up @@ -36,6 +36,17 @@
# For example, the 'make_array' instruction consumes 'count' items on the
# stack, but no additional items. While the 'send_stack' instruction consumes
# the 'receiver' and 'count' additional items.
#
# Finally, for instructions that alter the normal sequential flow of execution,
# the type of control flow change will be specified in curly braces, e.g.
# {:branch}. The control flow behavior defaults to :next, but for those
# instructions where control is (or may) change, one of the following flow
# types must be specified:
# :branch - for instructions that branch within the same method
# :send - for instructions that invoke another method
# :yield - for instructions that yield to a block
# :return - for instructions that return to the calling method
# :raise - for instructions that invoke exception handling

class InstructionParser
class ParseError < Exception; end
Expand Down Expand Up @@ -104,7 +115,7 @@ def opcode_define
end

class Instruction < Definition
attr_reader :name, :bytecode, :arguments, :consumed, :extra, :produced, :effect, :body
attr_reader :name, :bytecode, :arguments, :consumed, :extra, :produced, :effect, :body, :control_flow

def self.bytecodes
@bytecodes
Expand All @@ -122,6 +133,7 @@ def initialize(parser, header)
@body = []
@extra = nil
@bytecode = self.class.bytecode
@control_flow = :next
end

def parse
Expand All @@ -130,7 +142,7 @@ def parse
end

def parse_header
m = @header.match(/(\w+)\(([^)]*)\) \[ ([\w+ ]*)-- ([\w ]*)\]/)
m = @header.match(/(\w+)\(([^)]*)\) \[ ([\w+ ]*)-- ([\w ]*)\]( \{:(\w+)\})?/)
unless m
raise ParseError, "invalid instruction header '#{@header}' at #{@file.lineno}"
end
Expand All @@ -153,6 +165,8 @@ def parse_header
@produced = m[4].strip.split

@effect = @produced.size - @consumed.size

@control_flow = m[6] if m[6]
end

def parse_body
Expand All @@ -174,7 +188,10 @@ def opcode_definition(file)
stack = "[#{consumed}, #{@produced.size}],"
file.print ":stack => %-12s" % stack

file.puts ":args => [#{@arguments.map { |x| ":#{x}" }.join(", ")}]"
args = "[#{@arguments.map { |x| ":#{x}" }.join(", ")}],"
file.print ":args => %-20s" % args

file.puts ":control_flow => :#{@control_flow}"
end

def opcode_name
Expand Down Expand Up @@ -282,7 +299,7 @@ def parse

# Generated output methods

def generate_definitions(filename)
def generate_opcodes(filename)
File.open filename, "w" do |file|
file.puts "# *** This file is generated by InstructionParser ***"
file.puts
Expand Down
2 changes: 1 addition & 1 deletion rakelib/vm.rake
View file
Expand Up @@ -550,7 +550,7 @@ insn_deps = %w[ vm/gen
]

file "lib/compiler/opcodes.rb" => insn_deps do |t|
generate_instruction_file iparser, :generate_definitions, t.name
generate_instruction_file iparser, :generate_opcodes, t.name
end

file "vm/gen/instruction_names.hpp" => insn_deps do |t|
Expand Down
83 changes: 49 additions & 34 deletions vm/instructions.def
View file
Expand Up @@ -177,9 +177,8 @@ section "Flow control"
# [See Also]
# * goto_if_true
# * goto_if_false
# * goto_if_defined

instruction goto(location) [ -- ]
instruction goto(location) [ -- ] {:branch}
call_frame->set_ip(location);
cache_ip(location);
DISPATCH;
Expand All @@ -201,9 +200,8 @@ end
# [See Also]
# * goto
# * goto_if_false
# * goto_if_defined

instruction goto_if_false(location) [ ip -- ]
instruction goto_if_false(location) [ ip -- ] {:branch}
Object* t1 = stack_pop();
if(!RTEST(t1)) {
call_frame->set_ip(location);
Expand All @@ -228,9 +226,8 @@ end
# [See Also]
# * goto
# * goto_if_false
# * goto_if_defined

instruction goto_if_true(location) [ ip -- ]
instruction goto_if_true(location) [ ip -- ] {:branch}
Object* t1 = stack_pop();
if(RTEST(t1)) {
call_frame->set_ip(location);
Expand All @@ -255,7 +252,7 @@ end
# * caller_return
# * raise_exc

instruction ret() [ -- ]
instruction ret() [ -- ] {:return}
if(call_frame->scope->made_alias_p()) {
call_frame->scope->flush_to_heap(state);
}
Expand Down Expand Up @@ -329,17 +326,17 @@ end
# [Operation]
# Reverses the order on the stack of the top +count+ items
# [Format]
# \rotate count
# \rotate count
# [Stack Before]
# * obj1
# * obj2
# * obj3
# * ...
# * obj1
# * obj2
# * obj3
# * ...
# [Stack After]
# * obj3
# * obj2
# * obj1
# * ...
# * obj3
# * obj2
# * obj1
# * ...

instruction rotate(count) [ -- ]
int diff = count >> 1;
Expand All @@ -358,6 +355,24 @@ instruction rotate(count) [ -- ]
}
end

# [Operation]
# Moves the top item on the stack +positions+ lower down.
# [Format]
# \move_down
# [Stack Before]
# * obj1
# * obj2
# * ...
# * objn
# [Stack After]
# * obj2
# * ...
# * objn
# * obj1
# [Description]
# The top item on the stack is moved down by the specified number of
# +positions+, with all items above that position shuffling up by one.

instruction move_down(positions) [ -- ]
Object* val = stack_top();
for(int i = 0; i < positions; i++) {
Expand Down Expand Up @@ -626,7 +641,7 @@ end
# Pops an exception instance +exception+ off the stack, and uses it to
# raise an exception in the machine.

instruction raise_exc() [ -- ]
instruction raise_exc() [ -- ] {:raise}
flush_ip();
Object* t1 = stack_pop();
state->thread_state()->raise_exception(as<Exception>(t1));
Expand All @@ -646,7 +661,7 @@ instruction pop_unwind() [ -- ]
--current_unwind;
end

instruction raise_return() [ -- ]
instruction raise_return() [ -- ] {:raise}
flush_ip();
if(!(call_frame->flags & CallFrame::cIsLambda) &&
!call_frame->scope_still_valid(call_frame->scope->parent())) {
Expand All @@ -663,19 +678,19 @@ instruction raise_return() [ -- ]
RUN_EXCEPTION();
end

instruction ensure_return() [ -- ]
instruction ensure_return() [ -- ] {:raise}
flush_ip();
state->thread_state()->raise_return(stack_top(), call_frame->promote_scope(state));
RUN_EXCEPTION();
end

instruction raise_break() [ -- ]
instruction raise_break() [ -- ] {:raise}
flush_ip();
state->thread_state()->raise_break(stack_top(), call_frame->scope->parent());
RUN_EXCEPTION();
end

instruction reraise() [ -- ]
instruction reraise() [ -- ] {:raise}
assert(state->thread_state()->raise_reason() != cNone);
RUN_EXCEPTION();
end
Expand Down Expand Up @@ -1110,7 +1125,7 @@ end
# This form of send is for methods that take no arguments.
#

instruction send_method(literal) [ receiver -- value ]
instruction send_method(literal) [ receiver -- value ] {:send}
flush_ip();
Object* recv = stack_top();
InlineCache* cache = reinterpret_cast<InlineCache*>(literal);
Expand Down Expand Up @@ -1153,7 +1168,7 @@ end
# send_stack_with_block for the equivalent op code used when a block is to
# be passed.

instruction send_stack(literal count) [ receiver +count -- value ]
instruction send_stack(literal count) [ receiver +count -- value ] {:send}
flush_ip();
Object* recv = stack_back(count);
InlineCache* cache = reinterpret_cast<InlineCache*>(literal);
Expand Down Expand Up @@ -1198,7 +1213,7 @@ end
# This opcode passes a block to the receiver; see send_stack for the
# equivalent op code used when no block is to be passed.

instruction send_stack_with_block(literal count) [ block receiver +count -- value ]
instruction send_stack_with_block(literal count) [ block receiver +count -- value ] {:send}
flush_ip();
Object* block = stack_pop();
Object* recv = stack_back(count);
Expand Down Expand Up @@ -1245,7 +1260,7 @@ end

define CALL_FLAG_CONCAT 2

instruction send_stack_with_splat(literal count) [ block array receiver +count -- value ]
instruction send_stack_with_splat(literal count) [ block array receiver +count -- value ] {:send}
flush_ip();
Object* block = stack_pop();
Object* ary = stack_pop();
Expand Down Expand Up @@ -1297,7 +1312,7 @@ end
# The receiver is not specified for a call to super; it is the superclass
# of the current object that will receive the message.

instruction send_super_stack_with_block(literal count) [ block +count -- value ]
instruction send_super_stack_with_block(literal count) [ block +count -- value ] {:send}
flush_ip();
Object* block = stack_pop();
InlineCache* cache = reinterpret_cast<InlineCache*>(literal);
Expand Down Expand Up @@ -1347,7 +1362,7 @@ end
#
# When the method returns, the return value will be on top of the stack.

instruction send_super_stack_with_splat(literal count) [ block array +count -- value ]
instruction send_super_stack_with_splat(literal count) [ block array +count -- value ] {:send}
flush_ip();
Object* block = stack_pop();
Object* ary = stack_pop();
Expand Down Expand Up @@ -1558,7 +1573,7 @@ instruction cast_for_splat_block_arg() [ -- arguments ]
stack_push(ary);
end

instruction yield_stack(count) [ +count -- value ]
instruction yield_stack(count) [ +count -- value ] {:yield}
flush_ip();
Object* t1 = call_frame->scope->block();
Object* ret;
Expand All @@ -1582,7 +1597,7 @@ instruction yield_stack(count) [ +count -- value ]
stack_push(ret);
end

instruction yield_splat(count) [ array +count -- value ]
instruction yield_splat(count) [ array +count -- value ] {:yield}
flush_ip();
Object* ary = stack_pop();
Object* t1 = call_frame->scope->block();
Expand Down Expand Up @@ -2060,7 +2075,7 @@ end
# addition is done directly via the fixnum_add primitive; otherwise, the +
# method is called on +value1+, passing +value2+ as the argument.

instruction meta_send_op_plus(literal) [ value1 value2 -- sum ]
instruction meta_send_op_plus(literal) [ value1 value2 -- sum ] {:send}
Object* left = stack_back(1);
Object* right = stack_back(0);

Expand Down Expand Up @@ -2098,7 +2113,7 @@ end
# subtraction is done directly via the fixnum_sub primitive; otherwise,
# the - method is called on +value1+, passing +value2+ as the argument.

instruction meta_send_op_minus(literal) [ value1 value2 -- difference ]
instruction meta_send_op_minus(literal) [ value1 value2 -- difference ] {:send}
Object* left = stack_back(1);
Object* right = stack_back(0);

Expand Down Expand Up @@ -2134,7 +2149,7 @@ end
# both symbols, the comparison is done directly; otherwise, the == method
# is called on +value1+, passing +value2+ as the argument.

instruction meta_send_op_equal(literal) [ value1 value2 -- boolean ]
instruction meta_send_op_equal(literal) [ value1 value2 -- boolean ] {:send}
Object* t1 = stack_back(1);
Object* t2 = stack_back(0);
/* If both are not references, compare them directly. */
Expand Down Expand Up @@ -2247,7 +2262,7 @@ end
# [Notes]
# Exactly like equal, except calls === if it can't handle it directly.

instruction meta_send_op_tequal(literal) [ value1 value2 -- boolean ]
instruction meta_send_op_tequal(literal) [ value1 value2 -- boolean ] {:send}
Object* t1 = stack_back(1);
Object* t2 = stack_back(0);
/* If both are fixnums, or both are symbols, compare the ops directly. */
Expand Down Expand Up @@ -2280,7 +2295,7 @@ end
# [Description]
# Simplified call instruction used for yields and basic calls

instruction meta_send_call(literal count) [ receiver +count -- value ]
instruction meta_send_call(literal count) [ receiver +count -- value ] {:send}
flush_ip();
Object* t1 = stack_back(count);
Object* ret;
Expand Down

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