From c02bf4515c5a2ebcc1381f8d58a833c3498cfa88 Mon Sep 17 00:00:00 2001 From: "yangguo@chromium.org" Date: Fri, 5 Apr 2013 12:06:34 +0000 Subject: [PATCH] Remove push(holder_reg) in CheckAccessGlobalProxy. R=jkummerow@chromium.org BUG=v8:119 Review URL: https://chromiumcodereview.appspot.com/13177002 git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14150 ce2b1a6d-e550-0410-aec6-3dcde31c8c00 --- src/arm/macro-assembler-arm.cc | 2 -- src/ia32/macro-assembler-ia32.cc | 40 ++++++++++++++++++---------------------- src/ia32/macro-assembler-ia32.h | 3 ++- src/ia32/stub-cache-ia32.cc | 18 ++++++++++-------- src/mips/macro-assembler-mips.cc | 2 -- 5 files changed, 30 insertions(+), 35 deletions(-) diff --git a/src/arm/macro-assembler-arm.cc b/src/arm/macro-assembler-arm.cc index bacf570..ecedfd8 100644 --- a/src/arm/macro-assembler-arm.cc +++ b/src/arm/macro-assembler-arm.cc @@ -1402,7 +1402,6 @@ void MacroAssembler::CheckAccessGlobalProxy(Register holder_reg, // Check the context is a native context. if (emit_debug_code()) { - // TODO(119): avoid push(holder_reg)/pop(holder_reg) // Cannot use ip as a temporary in this verification code. Due to the fact // that ip is clobbered as part of cmp with an object Operand. push(holder_reg); // Temporarily save holder on the stack. @@ -1421,7 +1420,6 @@ void MacroAssembler::CheckAccessGlobalProxy(Register holder_reg, // Check the context is a native context. if (emit_debug_code()) { - // TODO(119): avoid push(holder_reg)/pop(holder_reg) // Cannot use ip as a temporary in this verification code. Due to the fact // that ip is clobbered as part of cmp with an object Operand. push(holder_reg); // Temporarily save holder on the stack. diff --git a/src/ia32/macro-assembler-ia32.cc b/src/ia32/macro-assembler-ia32.cc index 3d3dabc..da4e339 100644 --- a/src/ia32/macro-assembler-ia32.cc +++ b/src/ia32/macro-assembler-ia32.cc @@ -1024,69 +1024,65 @@ void MacroAssembler::ThrowUncatchable(Register value) { void MacroAssembler::CheckAccessGlobalProxy(Register holder_reg, - Register scratch, + Register scratch1, + Register scratch2, Label* miss) { Label same_contexts; - ASSERT(!holder_reg.is(scratch)); + ASSERT(!holder_reg.is(scratch1)); + ASSERT(!holder_reg.is(scratch2)); + ASSERT(!scratch1.is(scratch2)); // Load current lexical context from the stack frame. - mov(scratch, Operand(ebp, StandardFrameConstants::kContextOffset)); + mov(scratch1, Operand(ebp, StandardFrameConstants::kContextOffset)); // When generating debug code, make sure the lexical context is set. if (emit_debug_code()) { - cmp(scratch, Immediate(0)); + cmp(scratch1, Immediate(0)); Check(not_equal, "we should not have an empty lexical context"); } // Load the native context of the current context. int offset = Context::kHeaderSize + Context::GLOBAL_OBJECT_INDEX * kPointerSize; - mov(scratch, FieldOperand(scratch, offset)); - mov(scratch, FieldOperand(scratch, GlobalObject::kNativeContextOffset)); + mov(scratch1, FieldOperand(scratch1, offset)); + mov(scratch1, FieldOperand(scratch1, GlobalObject::kNativeContextOffset)); // Check the context is a native context. if (emit_debug_code()) { - push(scratch); // Read the first word and compare to native_context_map. - mov(scratch, FieldOperand(scratch, HeapObject::kMapOffset)); - cmp(scratch, isolate()->factory()->native_context_map()); + cmp(FieldOperand(scratch1, HeapObject::kMapOffset), + isolate()->factory()->native_context_map()); Check(equal, "JSGlobalObject::native_context should be a native context."); - pop(scratch); } // Check if both contexts are the same. - cmp(scratch, FieldOperand(holder_reg, JSGlobalProxy::kNativeContextOffset)); + cmp(scratch1, FieldOperand(holder_reg, JSGlobalProxy::kNativeContextOffset)); j(equal, &same_contexts); // Compare security tokens, save holder_reg on the stack so we can use it // as a temporary register. // - // TODO(119): avoid push(holder_reg)/pop(holder_reg) - push(holder_reg); // Check that the security token in the calling global object is // compatible with the security token in the receiving global // object. - mov(holder_reg, + mov(scratch2, FieldOperand(holder_reg, JSGlobalProxy::kNativeContextOffset)); // Check the context is a native context. if (emit_debug_code()) { - cmp(holder_reg, isolate()->factory()->null_value()); + cmp(scratch2, isolate()->factory()->null_value()); Check(not_equal, "JSGlobalProxy::context() should not be null."); - push(holder_reg); // Read the first word and compare to native_context_map(), - mov(holder_reg, FieldOperand(holder_reg, HeapObject::kMapOffset)); - cmp(holder_reg, isolate()->factory()->native_context_map()); + cmp(FieldOperand(scratch2, HeapObject::kMapOffset), + isolate()->factory()->native_context_map()); Check(equal, "JSGlobalObject::native_context should be a native context."); - pop(holder_reg); } int token_offset = Context::kHeaderSize + Context::SECURITY_TOKEN_INDEX * kPointerSize; - mov(scratch, FieldOperand(scratch, token_offset)); - cmp(scratch, FieldOperand(holder_reg, token_offset)); - pop(holder_reg); + mov(scratch1, FieldOperand(scratch1, token_offset)); + cmp(scratch1, FieldOperand(scratch2, token_offset)); j(not_equal, miss); bind(&same_contexts); diff --git a/src/ia32/macro-assembler-ia32.h b/src/ia32/macro-assembler-ia32.h index b3dae73..5b91ae4 100644 --- a/src/ia32/macro-assembler-ia32.h +++ b/src/ia32/macro-assembler-ia32.h @@ -548,7 +548,8 @@ class MacroAssembler: public Assembler { // on access to global objects across environments. The holder register // is left untouched, but the scratch register is clobbered. void CheckAccessGlobalProxy(Register holder_reg, - Register scratch, + Register scratch1, + Register scratch2, Label* miss); void GetNumberHash(Register r0, Register scratch); diff --git a/src/ia32/stub-cache-ia32.cc b/src/ia32/stub-cache-ia32.cc index cb4b4a7..fbe3351 100644 --- a/src/ia32/stub-cache-ia32.cc +++ b/src/ia32/stub-cache-ia32.cc @@ -748,7 +748,7 @@ void StubCompiler::GenerateStoreField(MacroAssembler* masm, // Perform global security token check if needed. if (object->IsJSGlobalProxy()) { - __ CheckAccessGlobalProxy(receiver_reg, scratch1, miss_label); + __ CheckAccessGlobalProxy(receiver_reg, scratch1, scratch2, miss_label); } // Check that we are allowed to write this. @@ -972,10 +972,6 @@ Register StubCompiler::CheckPrototypes(Handle object, } else { bool in_new_space = heap()->InNewSpace(*prototype); Handle current_map(current->map()); - if (in_new_space) { - // Save the map in scratch1 for later. - __ mov(scratch1, FieldOperand(reg, HeapObject::kMapOffset)); - } if (!current.is_identical_to(first) || check == CHECK_ALL_MAPS) { __ CheckMap(reg, current_map, miss, DONT_DO_SMI_CHECK, ALLOW_ELEMENT_TRANSITION_MAPS); @@ -985,8 +981,14 @@ Register StubCompiler::CheckPrototypes(Handle object, // the map check so that we know that the object is actually a global // object. if (current->IsJSGlobalProxy()) { - __ CheckAccessGlobalProxy(reg, scratch2, miss); + __ CheckAccessGlobalProxy(reg, scratch1, scratch2, miss); + } + + if (in_new_space) { + // Save the map in scratch1 for later. + __ mov(scratch1, FieldOperand(reg, HeapObject::kMapOffset)); } + reg = holder_reg; // From now on the object will be in holder_reg. if (in_new_space) { @@ -1020,7 +1022,7 @@ Register StubCompiler::CheckPrototypes(Handle object, // Perform security check for access to the global object. ASSERT(holder->IsJSGlobalProxy() || !holder->IsAccessCheckNeeded()); if (holder->IsJSGlobalProxy()) { - __ CheckAccessGlobalProxy(reg, scratch1, miss); + __ CheckAccessGlobalProxy(reg, scratch1, scratch2, miss); } // If we've skipped any global objects, it's not enough to verify that @@ -2657,7 +2659,7 @@ Handle StoreStubCompiler::CompileStoreInterceptor( // Perform global security token check if needed. if (object->IsJSGlobalProxy()) { - __ CheckAccessGlobalProxy(edx, ebx, &miss); + __ CheckAccessGlobalProxy(receiver(), scratch1(), scratch2(), &miss); } // Stub never generated for non-global objects that require access diff --git a/src/mips/macro-assembler-mips.cc b/src/mips/macro-assembler-mips.cc index 12e1025..3a3a3f3 100644 --- a/src/mips/macro-assembler-mips.cc +++ b/src/mips/macro-assembler-mips.cc @@ -369,7 +369,6 @@ void MacroAssembler::CheckAccessGlobalProxy(Register holder_reg, // Check the context is a native context. if (emit_debug_code()) { - // TODO(119): Avoid push(holder_reg)/pop(holder_reg). push(holder_reg); // Temporarily save holder on the stack. // Read the first word and compare to the native_context_map. lw(holder_reg, FieldMemOperand(scratch, HeapObject::kMapOffset)); @@ -385,7 +384,6 @@ void MacroAssembler::CheckAccessGlobalProxy(Register holder_reg, // Check the context is a native context. if (emit_debug_code()) { - // TODO(119): Avoid push(holder_reg)/pop(holder_reg). push(holder_reg); // Temporarily save holder on the stack. mov(holder_reg, at); // Move at to its holding place. LoadRoot(at, Heap::kNullValueRootIndex); -- 2.7.4