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Simplify the way we materialize boolean values that are not yet pushed

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on the stack frame.
Review URL: http://codereview.chromium.org/8764

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@671 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
kmillikin@chromium.org 2008-10-31 11:55:06 +00:00
parent bf3efa1c72
commit 67ae89e417
2 changed files with 30 additions and 43 deletions
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36
src/codegen-arm.cc
View File

@ -359,47 +359,41 @@ void CodeGenerator::Load(Expression* x, TypeofState typeof_state) {
Label false_target;
LoadCondition(x, typeof_state, &true_target, &false_target, false);
// Materialize boolean values on the stack frame if necessary.
if (has_cc()) {
// convert cc_reg_ into a bool
Label loaded, materialize_true;
__ b(cc_reg_, &materialize_true);
// The value we want is in the cc register. Since complicated
// conditions can require more than one test, there may also be branches
// to true_target and false_target.
Label loaded;
__ b(cc_reg_, &true_target);
__ bind(&false_target);
__ mov(r0, Operand(Factory::false_value()));
__ push(r0);
__ b(&loaded);
__ bind(&materialize_true);
__ bind(&true_target);
__ mov(r0, Operand(Factory::true_value()));
__ push(r0);
__ bind(&loaded);
cc_reg_ = al;
}
} else {
// Optimization of boolean-valued expressions whose value is statically
// known may have generated an unconditional jump to either of the
// targets (but not both) and failed to leave a value in either the cc
// register or on top of the frame.
ASSERT(!(true_target.is_linked() && false_target.is_linked()));
if (true_target.is_linked() || false_target.is_linked()) {
// we have at least one condition value
// that has been "translated" into a branch,
// thus it needs to be loaded explicitly again
Label loaded;
__ b(&loaded); // don't lose current TOS
bool both = true_target.is_linked() && false_target.is_linked();
// reincarnate "true", if necessary
if (true_target.is_linked()) {
__ bind(&true_target);
__ mov(r0, Operand(Factory::true_value()));
__ push(r0);
}
// if both "true" and "false" need to be reincarnated,
// jump across code for "false"
if (both)
__ b(&loaded);
// reincarnate "false", if necessary
if (false_target.is_linked()) {
__ bind(&false_target);
__ mov(r0, Operand(Factory::false_value()));
__ push(r0);
}
// everything is loaded at this point
__ bind(&loaded);
}
ASSERT(!has_cc());
}

37
src/codegen-ia32.cc
View File

@ -474,44 +474,37 @@ void CodeGenerator::Load(Expression* x, TypeofState typeof_state) {
Label false_target;
LoadCondition(x, typeof_state, &true_target, &false_target, false);
// Materialize boolean values on the stack frame if necessary.
if (has_cc()) {
// convert cc_reg_ into a bool
Label loaded, materialize_true;
__ j(cc_reg_, &materialize_true);
// The value we want is in the cc register. Since complicated
// conditions can require more than one test, there may also be branches
// to true_target and false_target.
Label loaded;
__ j(cc_reg_, &true_target);
__ bind(&false_target);
frame_->Push(Immediate(Factory::false_value()));
__ jmp(&loaded);
__ bind(&materialize_true);
__ bind(&true_target);
frame_->Push(Immediate(Factory::true_value()));
__ bind(&loaded);
cc_reg_ = no_condition;
}
} else {
// Optimization of boolean-valued expressions whose value is statically
// known may have generated an unconditional jump to either of the
// targets (but not both) and failed to leave a value in either the cc
// register or on top of the frame.
ASSERT(!(true_target.is_linked() && false_target.is_linked()));
if (true_target.is_linked() || false_target.is_linked()) {
// we have at least one condition value
// that has been "translated" into a branch,
// thus it needs to be loaded explicitly again
Label loaded;
__ jmp(&loaded); // don't lose current TOS
bool both = true_target.is_linked() && false_target.is_linked();
// reincarnate "true", if necessary
if (true_target.is_linked()) {
__ bind(&true_target);
frame_->Push(Immediate(Factory::true_value()));
}
// if both "true" and "false" need to be reincarnated,
// jump across code for "false"
if (both)
__ jmp(&loaded);
// reincarnate "false", if necessary
if (false_target.is_linked()) {
__ bind(&false_target);
frame_->Push(Immediate(Factory::false_value()));
}
// everything is loaded at this point
__ bind(&loaded);
}
ASSERT(!has_cc());
}