Author: [EMAIL PROTECTED]
Date: Fri Oct 31 04:55:06 2008
New Revision: 671
Modified:
branches/bleeding_edge/src/codegen-arm.cc
branches/bleeding_edge/src/codegen-ia32.cc
Log:
Simplify the way we materialize boolean values that are not yet pushed
on the stack frame.
Review URL: http://codereview.chromium.org/8764
Modified: branches/bleeding_edge/src/codegen-arm.cc
==============================================================================
--- branches/bleeding_edge/src/codegen-arm.cc (original)
+++ branches/bleeding_edge/src/codegen-arm.cc Fri Oct 31 04:55:06 2008
@@ -359,47 +359,41 @@
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());
}
Modified: branches/bleeding_edge/src/codegen-ia32.cc
==============================================================================
--- branches/bleeding_edge/src/codegen-ia32.cc (original)
+++ branches/bleeding_edge/src/codegen-ia32.cc Fri Oct 31 04:55:06 2008
@@ -474,44 +474,37 @@
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());
}
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