AuroraMiddleware/v8
1
0
Fork 0
Code Issues 2 Pull Requests Releases Wiki Activity

First round of JumpTarget simplification. Remove dead functions (jumps,

Browse Source 
branches, and bind with more than two arguments).  Remove unneeded
variable (the "watermark" on virtual frames).

Review URL: http://codereview.chromium.org/125045

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2153 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
kmillikin@chromium.org 2009-06-12 11:25:13 +00:00
parent f706cfa30c
commit b318835cdc
8 changed files with 34 additions and 205 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
src/arm/jump-target-arm.cc
View File

@ -149,7 +149,7 @@ void JumpTarget::Call() {
}
void JumpTarget::DoBind(int mergable_elements) {
void JumpTarget::DoBind() {
ASSERT(!is_bound());
// Live non-frame registers are not allowed at the start of a basic
@ -207,7 +207,7 @@ void JumpTarget::DoBind(int mergable_elements) {
// Compute the frame to use for entry to the block.
if (entry_frame_ == NULL) {
ComputeEntryFrame(mergable_elements);
ComputeEntryFrame();
}
// Some moves required to merge to an expected frame require purely

12
src/ia32/codegen-ia32.cc
View File

@ -317,9 +317,7 @@ void CodeGenerator::GenCode(FunctionLiteral* fun) {
if (function_return_.is_bound()) {
function_return_.Jump(&undefined);
} else {
// Though this is a (possibly) backward block, the frames
// can only differ on their top element.
function_return_.Bind(&undefined, 1);
function_return_.Bind(&undefined);
GenerateReturnSequence(&undefined);
}
} else if (function_return_.is_linked()) {
@ -329,9 +327,7 @@ void CodeGenerator::GenCode(FunctionLiteral* fun) {
// compile an artificial return statement just above, and (b) there
// are return statements in the body but (c) they are all shadowed.
Result return_value;
// Though this is a (possibly) backward block, the frames can
// only differ on their top element.
function_return_.Bind(&return_value, 1);
function_return_.Bind(&return_value);
GenerateReturnSequence(&return_value);
}
}
@ -2328,9 +2324,7 @@ void CodeGenerator::VisitReturnStatement(ReturnStatement* node) {
// code by jumping to the return site.
function_return_.Jump(&return_value);
} else {
// Though this is a (possibly) backward block, the frames can
// only differ on their top element.
function_return_.Bind(&return_value, 1);
function_return_.Bind(&return_value);
GenerateReturnSequence(&return_value);
}
}

6
src/ia32/jump-target-ia32.cc
View File

@ -164,7 +164,7 @@ void JumpTarget::Call() {
}
void JumpTarget::DoBind(int mergable_elements) {
void JumpTarget::DoBind() {
ASSERT(cgen() != NULL);
ASSERT(!is_bound());
@ -210,7 +210,7 @@ void JumpTarget::DoBind(int mergable_elements) {
// Fast case: no forward jumps, possible backward ones. Remove
// constants and copies above the watermark on the fall-through
// frame and use it as the entry frame.
cgen()->frame()->MakeMergable(mergable_elements);
cgen()->frame()->MakeMergable();
entry_frame_ = new VirtualFrame(cgen()->frame());
}
__ bind(&entry_label_);
@ -252,7 +252,7 @@ void JumpTarget::DoBind(int mergable_elements) {
}
// Compute the frame to use for entry to the block.
ComputeEntryFrame(mergable_elements);
ComputeEntryFrame();
// Some moves required to merge to an expected frame require purely
// frame state changes, and do not require any code generation.

10
src/ia32/virtual-frame-ia32.cc
View File

@ -174,14 +174,8 @@ void VirtualFrame::SyncRange(int begin, int end) {
}
void VirtualFrame::MakeMergable(int mergable_elements) {
if (mergable_elements == JumpTarget::kAllElements) {
mergable_elements = element_count();
}
ASSERT(mergable_elements <= element_count());
int start_index = element_count() - mergable_elements;
for (int i = start_index; i < element_count(); i++) {
void VirtualFrame::MakeMergable() {
for (int i = 0; i < element_count(); i++) {
FrameElement element = elements_[i];
if (element.is_constant() || element.is_copy()) {

7
src/ia32/virtual-frame-ia32.h
View File

@ -153,11 +153,8 @@ class VirtualFrame : public ZoneObject {
void SyncRange(int begin, int end);
// Make this frame so that an arbitrary frame of the same height can
// be merged to it. Copies and constants are removed from the
// topmost mergable_elements elements of the frame. A
// mergable_elements of JumpTarget::kAllElements indicates constants
// and copies are should be removed from the entire frame.
void MakeMergable(int mergable_elements);
// be merged to it. Copies and constants are removed from the frame.
void MakeMergable();
// Prepare this virtual frame for merging to an expected frame by
// performing some state changes that do not require generating

147
src/jump-target.cc
View File

@ -48,7 +48,7 @@ void JumpTarget::Unuse() {
}
void JumpTarget::ComputeEntryFrame(int mergable_elements) {
void JumpTarget::ComputeEntryFrame() {
// Given: a collection of frames reaching by forward CFG edges and
// the directionality of the block. Compute: an entry frame for the
// block.
@ -77,14 +77,6 @@ void JumpTarget::ComputeEntryFrame(int mergable_elements) {
int length = initial_frame->element_count();
ZoneList<FrameElement*> elements(length);
// Convert the number of mergable elements (counted from the top
// down) to a frame high-water mark (counted from the bottom up).
// Elements strictly above the high-water index will be mergable in
// entry frames for bidirectional jump targets.
int high_water_mark = (mergable_elements == kAllElements)
? VirtualFrame::kIllegalIndex // All frame indices are above this.
: length - mergable_elements - 1; // Top index if m_e == 0.
// Initially populate the list of elements based on the initial
// frame.
for (int i = 0; i < length; i++) {
@ -92,7 +84,7 @@ void JumpTarget::ComputeEntryFrame(int mergable_elements) {
// We do not allow copies or constants in bidirectional frames. All
// elements above the water mark on bidirectional frames have
// unknown static types.
if (direction_ == BIDIRECTIONAL && i > high_water_mark) {
if (direction_ == BIDIRECTIONAL) {
if (element.is_constant() || element.is_copy()) {
elements.Add(NULL);
continue;
@ -158,7 +150,7 @@ void JumpTarget::ComputeEntryFrame(int mergable_elements) {
int best_reg_num = RegisterAllocator::kInvalidRegister;
StaticType type; // Initially invalid.
if (direction_ != BIDIRECTIONAL || i < high_water_mark) {
if (direction_ != BIDIRECTIONAL) {
type = reaching_frames_[0]->elements_[i].static_type();
}
@ -241,25 +233,6 @@ void JumpTarget::Jump(Result* arg) {
}
void JumpTarget::Jump(Result* arg0, Result* arg1) {
ASSERT(cgen()->has_valid_frame());
cgen()->frame()->Push(arg0);
cgen()->frame()->Push(arg1);
DoJump();
}
void JumpTarget::Jump(Result* arg0, Result* arg1, Result* arg2) {
ASSERT(cgen()->has_valid_frame());
cgen()->frame()->Push(arg0);
cgen()->frame()->Push(arg1);
cgen()->frame()->Push(arg2);
DoJump();
}
void JumpTarget::Branch(Condition cc, Hint hint) {
DoBranch(cc, hint);
}
@ -314,65 +287,6 @@ void JumpTarget::Branch(Condition cc, Result* arg0, Result* arg1, Hint hint) {
}
void JumpTarget::Branch(Condition cc,
Result* arg0,
Result* arg1,
Result* arg2,
Hint hint) {
ASSERT(cgen()->frame() != NULL);
// We want to check that non-frame registers at the call site stay in
// the same registers on the fall-through branch.
DECLARE_ARGCHECK_VARS(arg0);
DECLARE_ARGCHECK_VARS(arg1);
DECLARE_ARGCHECK_VARS(arg2);
cgen()->frame()->Push(arg0);
cgen()->frame()->Push(arg1);
cgen()->frame()->Push(arg2);
DoBranch(cc, hint);
*arg2 = cgen()->frame()->Pop();
*arg1 = cgen()->frame()->Pop();
*arg0 = cgen()->frame()->Pop();
ASSERT_ARGCHECK(arg0);
ASSERT_ARGCHECK(arg1);
ASSERT_ARGCHECK(arg2);
}
void JumpTarget::Branch(Condition cc,
Result* arg0,
Result* arg1,
Result* arg2,
Result* arg3,
Hint hint) {
ASSERT(cgen()->frame() != NULL);
// We want to check that non-frame registers at the call site stay in
// the same registers on the fall-through branch.
DECLARE_ARGCHECK_VARS(arg0);
DECLARE_ARGCHECK_VARS(arg1);
DECLARE_ARGCHECK_VARS(arg2);
DECLARE_ARGCHECK_VARS(arg3);
cgen()->frame()->Push(arg0);
cgen()->frame()->Push(arg1);
cgen()->frame()->Push(arg2);
cgen()->frame()->Push(arg3);
DoBranch(cc, hint);
*arg3 = cgen()->frame()->Pop();
*arg2 = cgen()->frame()->Pop();
*arg1 = cgen()->frame()->Pop();
*arg0 = cgen()->frame()->Pop();
ASSERT_ARGCHECK(arg0);
ASSERT_ARGCHECK(arg1);
ASSERT_ARGCHECK(arg2);
ASSERT_ARGCHECK(arg3);
}
void BreakTarget::Branch(Condition cc, Result* arg, Hint hint) {
ASSERT(cgen()->has_valid_frame());
@ -400,61 +314,26 @@ void BreakTarget::Branch(Condition cc, Result* arg, Hint hint) {
#undef ASSERT_ARGCHECK
void JumpTarget::Bind(int mergable_elements) {
DoBind(mergable_elements);
void JumpTarget::Bind() {
DoBind();
}
void JumpTarget::Bind(Result* arg, int mergable_elements) {
void JumpTarget::Bind(Result* arg) {
if (cgen()->has_valid_frame()) {
cgen()->frame()->Push(arg);
}
DoBind(mergable_elements);
DoBind();
*arg = cgen()->frame()->Pop();
}
void JumpTarget::Bind(Result* arg0, Result* arg1, int mergable_elements) {
void JumpTarget::Bind(Result* arg0, Result* arg1) {
if (cgen()->has_valid_frame()) {
cgen()->frame()->Push(arg0);
cgen()->frame()->Push(arg1);
}
DoBind(mergable_elements);
*arg1 = cgen()->frame()->Pop();
*arg0 = cgen()->frame()->Pop();
}
void JumpTarget::Bind(Result* arg0,
Result* arg1,
Result* arg2,
int mergable_elements) {
if (cgen()->has_valid_frame()) {
cgen()->frame()->Push(arg0);
cgen()->frame()->Push(arg1);
cgen()->frame()->Push(arg2);
}
DoBind(mergable_elements);
*arg2 = cgen()->frame()->Pop();
*arg1 = cgen()->frame()->Pop();
*arg0 = cgen()->frame()->Pop();
}
void JumpTarget::Bind(Result* arg0,
Result* arg1,
Result* arg2,
Result* arg3,
int mergable_elements) {
if (cgen()->has_valid_frame()) {
cgen()->frame()->Push(arg0);
cgen()->frame()->Push(arg1);
cgen()->frame()->Push(arg2);
cgen()->frame()->Push(arg3);
}
DoBind(mergable_elements);
*arg3 = cgen()->frame()->Pop();
*arg2 = cgen()->frame()->Pop();
DoBind();
*arg1 = cgen()->frame()->Pop();
*arg0 = cgen()->frame()->Pop();
}
@ -531,7 +410,7 @@ void BreakTarget::Branch(Condition cc, Hint hint) {
}
void BreakTarget::Bind(int mergable_elements) {
void BreakTarget::Bind() {
#ifdef DEBUG
// All the forward-reaching frames should have been adjusted at the
// jumps to this target.
@ -547,11 +426,11 @@ void BreakTarget::Bind(int mergable_elements) {
int count = cgen()->frame()->height() - expected_height_;
cgen()->frame()->ForgetElements(count);
}
DoBind(mergable_elements);
DoBind();
}
void BreakTarget::Bind(Result* arg, int mergable_elements) {
void BreakTarget::Bind(Result* arg) {
#ifdef DEBUG
// All the forward-reaching frames should have been adjusted at the
// jumps to this target.
@ -568,7 +447,7 @@ void BreakTarget::Bind(Result* arg, int mergable_elements) {
cgen()->frame()->ForgetElements(count);
cgen()->frame()->Push(arg);
}
DoBind(mergable_elements);
DoBind();
*arg = cgen()->frame()->Pop();
}

51
src/jump-target.h
View File

@ -107,8 +107,6 @@ class JumpTarget : public ZoneObject { // Shadows are dynamically allocated.
// jump and there will be no current frame after the jump.
virtual void Jump();
virtual void Jump(Result* arg);
void Jump(Result* arg0, Result* arg1);
void Jump(Result* arg0, Result* arg1, Result* arg2);
// Emit a conditional branch to the target. There must be a current
// frame at the branch. The current frame will fall through to the
@ -116,43 +114,13 @@ class JumpTarget : public ZoneObject { // Shadows are dynamically allocated.
virtual void Branch(Condition cc, Hint hint = no_hint);
virtual void Branch(Condition cc, Result* arg, Hint hint = no_hint);
void Branch(Condition cc, Result* arg0, Result* arg1, Hint hint = no_hint);
void Branch(Condition cc,
Result* arg0,
Result* arg1,
Result* arg2,
Hint hint = no_hint);
void Branch(Condition cc,
Result* arg0,
Result* arg1,
Result* arg2,
Result* arg3,
Hint hint = no_hint);
// Bind a jump target. If there is no current frame at the binding
// site, there must be at least one frame reaching via a forward
// jump.
//
// The number of mergable elements is a number of frame elements
// counting from the top down which must be "mergable" (not
// constants or copies) in the entry frame at the jump target.
// Backward jumps to the target must contain the same constants and
// sharing as the entry frame, except for the mergable elements.
//
// A mergable elements argument of kAllElements indicates that all
// frame elements must be mergable. Mergable elements are ignored
// completely for forward-only jump targets.
virtual void Bind(int mergable_elements = kAllElements);
virtual void Bind(Result* arg, int mergable_elements = kAllElements);
void Bind(Result* arg0, Result* arg1, int mergable_elements = kAllElements);
void Bind(Result* arg0,
Result* arg1,
Result* arg2,
int mergable_elements = kAllElements);
void Bind(Result* arg0,
Result* arg1,
Result* arg2,
Result* arg3,
int mergable_elements = kAllElements);
virtual void Bind();
virtual void Bind(Result* arg);
void Bind(Result* arg0, Result* arg1);
// Emit a call to a jump target. There must be a current frame at
// the call. The frame at the target is the same as the current
@ -160,8 +128,6 @@ class JumpTarget : public ZoneObject { // Shadows are dynamically allocated.
// after the call is the same as the frame before the call.
void Call();
static const int kAllElements = -1; // Not a valid number of elements.
static void set_compiling_deferred_code(bool flag) {
compiling_deferred_code_ = flag;
}
@ -188,7 +154,7 @@ class JumpTarget : public ZoneObject { // Shadows are dynamically allocated.
// return values using the virtual frame.
void DoJump();
void DoBranch(Condition cc, Hint hint);
void DoBind(int mergable_elements);
void DoBind();
private:
static bool compiling_deferred_code_;
@ -202,9 +168,8 @@ class JumpTarget : public ZoneObject { // Shadows are dynamically allocated.
// target.
inline void InitializeEntryElement(int index, FrameElement* target);
// Compute a frame to use for entry to this block. Mergable
// elements is as described for the Bind function.
void ComputeEntryFrame(int mergable_elements);
// Compute a frame to use for entry to this block.
void ComputeEntryFrame();
DISALLOW_COPY_AND_ASSIGN(JumpTarget);
};
@ -251,8 +216,8 @@ class BreakTarget : public JumpTarget {
// Bind a break target. If there is no current frame at the binding
// site, there must be at least one frame reaching via a forward
// jump.
virtual void Bind(int mergable_elements = kAllElements);
virtual void Bind(Result* arg, int mergable_elements = kAllElements);
virtual void Bind();
virtual void Bind(Result* arg);
// Setter for expected height.
void set_expected_height(int expected) { expected_height_ = expected; }

2
src/x64/assembler-x64.cc
View File

@ -1526,7 +1526,7 @@ Object* CallStubCompiler::CompileCallInterceptor(Object* a,
return NULL;
}
void JumpTarget::DoBind(int a) {
void JumpTarget::DoBind() {
UNIMPLEMENTED();
}