Handle all kind of arguments in the ToBooleanStub. While this is not very thrilling...

As a side note, this change has some positive impact on the performace, e.g. imaging-darkroom is 8.3% faster and ws-ieee754conv is even 19.9% faster. No idea why the speedup is so big in some cases, but never look a gift horse in the mouth... ;-)
Review URL: http://codereview.chromium.org/7042004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7926 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/arm/code-stubs-arm.cc b/src/arm/code-stubs-arm.cc
index 8120324..d510232 100644 (file)
--- a/src/arm/code-stubs-arm.cc
+++ b/src/arm/code-stubs-arm.cc
@@ -1616,12 +1616,36 @@ void CompareStub::Generate(MacroAssembler* masm) {
 // The stub returns zero for false, and a non-zero value for true.
 void ToBooleanStub::Generate(MacroAssembler* masm) {
   // This stub uses VFP3 instructions.
-  ASSERT(CpuFeatures::IsEnabled(VFP3));
+  CpuFeatures::Scope scope(VFP3);
 
   Label false_result;
   Label not_heap_number;
   Register scratch = r9.is(tos_) ? r7 : r9;
 
+  // undefined -> false
+  __ LoadRoot(ip, Heap::kUndefinedValueRootIndex);
+  __ cmp(tos_, ip);
+  __ b(eq, &false_result);
+
+  // Boolean -> its value
+  __ LoadRoot(ip, Heap::kFalseValueRootIndex);
+  __ cmp(tos_, ip);
+  __ b(eq, &false_result);
+  __ LoadRoot(ip, Heap::kTrueValueRootIndex);
+  __ cmp(tos_, ip);
+  // "tos_" is a register and contains a non-zero value.  Hence we implicitly
+  // return true if the equal condition is satisfied.
+  __ Ret(eq);
+
+  // Smis: 0 -> false, all other -> true
+  __ tst(tos_, tos_);
+  __ b(eq, &false_result);
+  __ tst(tos_, Operand(kSmiTagMask));
+  // "tos_" is a register and contains a non-zero value.  Hence we implicitly
+  // return true if the not equal condition is satisfied.
+  __ Ret(eq);
+
+  // 'null' -> false
   __ LoadRoot(ip, Heap::kNullValueRootIndex);
   __ cmp(tos_, ip);
   __ b(eq, &false_result);
@@ -1631,9 +1655,7 @@ void ToBooleanStub::Generate(MacroAssembler* masm) {
   __ LoadRoot(ip, Heap::kHeapNumberMapRootIndex);
   __ cmp(scratch, ip);
   __ b(&not_heap_number, ne);
-
-  __ sub(ip, tos_, Operand(kHeapObjectTag));
-  __ vldr(d1, ip, HeapNumber::kValueOffset);
+  __ vldr(d1, FieldMemOperand(tos_, HeapNumber::kValueOffset));
   __ VFPCompareAndSetFlags(d1, 0.0);
   // "tos_" is a register, and contains a non zero value by default.
   // Hence we only need to overwrite "tos_" with zero to return false for
@@ -1644,12 +1666,6 @@ void ToBooleanStub::Generate(MacroAssembler* masm) {
 
   __ bind(&not_heap_number);
 
-  // Check if the value is 'null'.
-  // 'null' => false.
-  __ LoadRoot(ip, Heap::kNullValueRootIndex);
-  __ cmp(tos_, ip);
-  __ b(&false_result, eq);
-
   // It can be an undetectable object.
   // Undetectable => false.
   __ ldr(ip, FieldMemOperand(tos_, HeapObject::kMapOffset));

diff --git a/src/arm/full-codegen-arm.cc b/src/arm/full-codegen-arm.cc
index 68a2355..2b7cdef 100644 (file)
--- a/src/arm/full-codegen-arm.cc
+++ b/src/arm/full-codegen-arm.cc
@@ -562,23 +562,6 @@ void FullCodeGenerator::DoTest(Label* if_true,
                                Label* if_false,
                                Label* fall_through) {
   if (CpuFeatures::IsSupported(VFP3)) {
-    CpuFeatures::Scope scope(VFP3);
-    // Emit the inlined tests assumed by the stub.
-    __ LoadRoot(ip, Heap::kUndefinedValueRootIndex);
-    __ cmp(result_register(), ip);
-    __ b(eq, if_false);
-    __ LoadRoot(ip, Heap::kTrueValueRootIndex);
-    __ cmp(result_register(), ip);
-    __ b(eq, if_true);
-    __ LoadRoot(ip, Heap::kFalseValueRootIndex);
-    __ cmp(result_register(), ip);
-    __ b(eq, if_false);
-    STATIC_ASSERT(kSmiTag == 0);
-    __ tst(result_register(), result_register());
-    __ b(eq, if_false);
-    __ JumpIfSmi(result_register(), if_true);
-
-    // Call the ToBoolean stub for all other cases.
     ToBooleanStub stub(result_register());
     __ CallStub(&stub);
     __ tst(result_register(), result_register());
@@ -590,8 +573,6 @@ void FullCodeGenerator::DoTest(Label* if_true,
     __ LoadRoot(ip, Heap::kFalseValueRootIndex);
     __ cmp(r0, ip);
   }
-
-  // The stub returns nonzero for true.
   Split(ne, if_true, if_false, fall_through);
 }
 

diff --git a/src/ia32/code-stubs-ia32.cc b/src/ia32/code-stubs-ia32.cc
index 534c187..ccac14c 100644 (file)
--- a/src/ia32/code-stubs-ia32.cc
+++ b/src/ia32/code-stubs-ia32.cc
@@ -244,9 +244,25 @@ void FastCloneShallowArrayStub::Generate(MacroAssembler* masm) {
 void ToBooleanStub::Generate(MacroAssembler* masm) {
   Label false_result, true_result, not_string;
   __ mov(eax, Operand(esp, 1 * kPointerSize));
+  Factory* factory = masm->isolate()->factory();
+
+  // undefined -> false
+  __ cmp(eax, factory->undefined_value());
+  __ j(equal, &false_result);
+
+  // Boolean -> its value
+  __ cmp(eax, factory->true_value());
+  __ j(equal, &true_result);
+  __ cmp(eax, factory->false_value());
+  __ j(equal, &false_result);
+
+  // Smis: 0 -> false, all other -> true
+  __ test(eax, Operand(eax));
+  __ j(zero, &false_result);
+  __ test(eax, Immediate(kSmiTagMask));
+  __ j(zero, &true_result);
 
   // 'null' => false.
-  Factory* factory = masm->isolate()->factory();
   __ cmp(eax, factory->null_value());
   __ j(equal, &false_result, Label::kNear);
 

diff --git a/src/ia32/full-codegen-ia32.cc b/src/ia32/full-codegen-ia32.cc
index 59c3373..d20e622 100644 (file)
--- a/src/ia32/full-codegen-ia32.cc
+++ b/src/ia32/full-codegen-ia32.cc
@@ -548,25 +548,10 @@ void FullCodeGenerator::TestContext::Plug(bool flag) const {
 void FullCodeGenerator::DoTest(Label* if_true,
                                Label* if_false,
                                Label* fall_through) {
-  // Emit the inlined tests assumed by the stub.
-  __ cmp(result_register(), isolate()->factory()->undefined_value());
-  __ j(equal, if_false);
-  __ cmp(result_register(), isolate()->factory()->true_value());
-  __ j(equal, if_true);
-  __ cmp(result_register(), isolate()->factory()->false_value());
-  __ j(equal, if_false);
-  STATIC_ASSERT(kSmiTag == 0);
-  __ test(result_register(), Operand(result_register()));
-  __ j(zero, if_false);
-  __ test(result_register(), Immediate(kSmiTagMask));
-  __ j(zero, if_true);
-
-  // Call the ToBoolean stub for all other cases.
   ToBooleanStub stub;
   __ push(result_register());
   __ CallStub(&stub);
   __ test(eax, Operand(eax));
-
   // The stub returns nonzero for true.
   Split(not_zero, if_true, if_false, fall_through);
 }

diff --git a/src/x64/code-stubs-x64.cc b/src/x64/code-stubs-x64.cc
index 702d06a..6fc6a17 100644 (file)
--- a/src/x64/code-stubs-x64.cc
+++ b/src/x64/code-stubs-x64.cc
@@ -235,6 +235,22 @@ void ToBooleanStub::Generate(MacroAssembler* masm) {
   Label false_result, true_result, not_string;
   __ movq(rax, Operand(rsp, 1 * kPointerSize));
 
+  // undefined -> false
+  __ CompareRoot(rax, Heap::kUndefinedValueRootIndex);
+  __ j(equal, &false_result);
+
+  // Boolean -> its value
+  __ CompareRoot(rax, Heap::kFalseValueRootIndex);
+  __ j(equal, &false_result);
+  __ CompareRoot(rax, Heap::kTrueValueRootIndex);
+  __ j(equal, &true_result);
+
+  // Smis: 0 -> false, all other -> true
+  __ Cmp(rax, Smi::FromInt(0));
+  __ j(equal, &false_result);
+  Condition is_smi = __ CheckSmi(rax);
+  __ j(is_smi, &true_result);
+
   // 'null' => false.
   __ CompareRoot(rax, Heap::kNullValueRootIndex);
   __ j(equal, &false_result, Label::kNear);

diff --git a/src/x64/full-codegen-x64.cc b/src/x64/full-codegen-x64.cc
index 3194e8a..d5a220f 100644 (file)
--- a/src/x64/full-codegen-x64.cc
+++ b/src/x64/full-codegen-x64.cc
@@ -553,25 +553,10 @@ void FullCodeGenerator::TestContext::Plug(bool flag) const {
 void FullCodeGenerator::DoTest(Label* if_true,
                                Label* if_false,
                                Label* fall_through) {
-  // Emit the inlined tests assumed by the stub.
-  __ CompareRoot(result_register(), Heap::kUndefinedValueRootIndex);
-  __ j(equal, if_false);
-  __ CompareRoot(result_register(), Heap::kTrueValueRootIndex);
-  __ j(equal, if_true);
-  __ CompareRoot(result_register(), Heap::kFalseValueRootIndex);
-  __ j(equal, if_false);
-  STATIC_ASSERT(kSmiTag == 0);
-  __ Cmp(result_register(), Smi::FromInt(0));
-  __ j(equal, if_false);
-  Condition is_smi = masm_->CheckSmi(result_register());
-  __ j(is_smi, if_true);
-
-  // Call the ToBoolean stub for all other cases.
   ToBooleanStub stub;
   __ push(result_register());
   __ CallStub(&stub);
   __ testq(rax, rax);
-
   // The stub returns nonzero for true.
   Split(not_zero, if_true, if_false, fall_through);
 }