Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(94)

Unified Diff: src/x64/macro-assembler-x64.cc

Issue 8462010: Add a level of indirection to exception handler addresses. (Closed) Base URL: https://v8.googlecode.com/svn/branches/bleeding_edge
Patch Set: Incorporate review changes. Created 9 years, 1 month ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View side-by-side diff with in-line comments
Download patch
« no previous file with comments | « src/x64/macro-assembler-x64.h ('k') | no next file » | no next file with comments »
Expand Comments ('e') | Collapse Comments ('c') | Show Comments Hide Comments ('s')
Index: src/x64/macro-assembler-x64.cc
diff --git a/src/x64/macro-assembler-x64.cc b/src/x64/macro-assembler-x64.cc
index 39670cc711e011da9f1bf6cd2abf6a6c2da61284..caca628f1fe9712ddf3c59a7c1991ad4055dff15 100644
--- a/src/x64/macro-assembler-x64.cc
+++ b/src/x64/macro-assembler-x64.cc
@@ -2417,86 +2417,105 @@ Operand MacroAssembler::SafepointRegisterSlot(Register reg) {
void MacroAssembler::PushTryHandler(CodeLocation try_location,
- HandlerType type) {
+ HandlerType type,
+ int handler_index) {
// Adjust this code if not the case.
STATIC_ASSERT(StackHandlerConstants::kSize == 5 * kPointerSize);
- STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0 * kPointerSize);
- STATIC_ASSERT(StackHandlerConstants::kContextOffset == 1 * kPointerSize);
- STATIC_ASSERT(StackHandlerConstants::kFPOffset == 2 * kPointerSize);
- STATIC_ASSERT(StackHandlerConstants::kStateOffset == 3 * kPointerSize);
- STATIC_ASSERT(StackHandlerConstants::kPCOffset == 4 * kPointerSize);
-
- // The pc (return address) is already on TOS. This code pushes state,
- // frame pointer, context, and current handler.
+ STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0);
+ STATIC_ASSERT(StackHandlerConstants::kCodeOffset == 1 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kStateOffset == 2 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kContextOffset == 3 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kFPOffset == 4 * kPointerSize);
+
+ // We will build up the handler from the bottom by pushing on the stack.
+ // First compute the state and push the frame pointer and context.
+ unsigned state = StackHandler::OffsetField::encode(handler_index);
if (try_location == IN_JAVASCRIPT) {
- if (type == TRY_CATCH_HANDLER) {
- push(Immediate(StackHandler::TRY_CATCH));
- } else {
- push(Immediate(StackHandler::TRY_FINALLY));
- }
push(rbp);
push(rsi);
+ state |= (type == TRY_CATCH_HANDLER)
+ ? StackHandler::KindField::encode(StackHandler::TRY_CATCH)
+ : StackHandler::KindField::encode(StackHandler::TRY_FINALLY);
} else {
ASSERT(try_location == IN_JS_ENTRY);
- // The frame pointer does not point to a JS frame so we save NULL
- // for rbp. We expect the code throwing an exception to check rbp
- // before dereferencing it to restore the context.
- push(Immediate(StackHandler::ENTRY));
+ // The frame pointer does not point to a JS frame so we save NULL for
+ // rbp. We expect the code throwing an exception to check rbp before
+ // dereferencing it to restore the context.
push(Immediate(0)); // NULL frame pointer.
Push(Smi::FromInt(0)); // No context.
+ state |= StackHandler::KindField::encode(StackHandler::ENTRY);
}
- // Save the current handler.
- Operand handler_operand =
- ExternalOperand(ExternalReference(Isolate::kHandlerAddress, isolate()));
- push(handler_operand);
- // Link this handler.
- movq(handler_operand, rsp);
+
+ // Push the state and the code object.
+ push(Immediate(state));
+ Push(CodeObject());
+
+ // Link the current handler as the next handler.
+ ExternalReference handler_address(Isolate::kHandlerAddress, isolate());
+ push(ExternalOperand(handler_address));
+ // Set this new handler as the current one.
+ movq(ExternalOperand(handler_address), rsp);
}
void MacroAssembler::PopTryHandler() {
- ASSERT_EQ(0, StackHandlerConstants::kNextOffset);
- // Unlink this handler.
- Operand handler_operand =
- ExternalOperand(ExternalReference(Isolate::kHandlerAddress, isolate()));
- pop(handler_operand);
- // Remove the remaining fields.
+ STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0);
+ ExternalReference handler_address(Isolate::kHandlerAddress, isolate());
+ pop(ExternalOperand(handler_address));
addq(rsp, Immediate(StackHandlerConstants::kSize - kPointerSize));
}
+void MacroAssembler::JumpToHandlerEntry() {
+ // Compute the handler entry address and jump to it. The handler table is
+ // a fixed array of (smi-tagged) code offsets.
+ // rax = exception, rdi = code object, rdx = state.
+ movq(rbx, FieldOperand(rdi, Code::kHandlerTableOffset));
+ shr(rdx, Immediate(StackHandler::kKindWidth));
+ movq(rdx, FieldOperand(rbx, rdx, times_8, FixedArray::kHeaderSize));
+ SmiToInteger64(rdx, rdx);
+ lea(rdi, FieldOperand(rdi, rdx, times_1, Code::kHeaderSize));
+ jmp(rdi);
+}
+
+
void MacroAssembler::Throw(Register value) {
// Adjust this code if not the case.
STATIC_ASSERT(StackHandlerConstants::kSize == 5 * kPointerSize);
- STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0 * kPointerSize);
- STATIC_ASSERT(StackHandlerConstants::kContextOffset == 1 * kPointerSize);
- STATIC_ASSERT(StackHandlerConstants::kFPOffset == 2 * kPointerSize);
- STATIC_ASSERT(StackHandlerConstants::kStateOffset == 3 * kPointerSize);
- STATIC_ASSERT(StackHandlerConstants::kPCOffset == 4 * kPointerSize);
- // Keep thrown value in rax.
+ STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0);
+ STATIC_ASSERT(StackHandlerConstants::kCodeOffset == 1 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kStateOffset == 2 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kContextOffset == 3 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kFPOffset == 4 * kPointerSize);
+
+ // The exception is expected in rax.
if (!value.is(rax)) {
movq(rax, value);
}
-
+ // Drop the stack pointer to the top of the top handler.
ExternalReference handler_address(Isolate::kHandlerAddress, isolate());
- Operand handler_operand = ExternalOperand(handler_address);
- movq(rsp, handler_operand);
- // get next in chain
- pop(handler_operand);
+ movq(rsp, ExternalOperand(handler_address));
+ // Restore the next handler.
+ pop(ExternalOperand(handler_address));
+
+ // Remove the code object and state, compute the handler address in rdi.
+ pop(rdi); // Code object.
+ pop(rdx); // Offset and state.
+
+ // Restore the context and frame pointer.
pop(rsi); // Context.
pop(rbp); // Frame pointer.
- pop(rdx); // State.
// If the handler is a JS frame, restore the context to the frame.
- // (rdx == ENTRY) == (rbp == 0) == (rsi == 0), so we could test any
- // of them.
+ // (kind == ENTRY) == (rbp == 0) == (rsi == 0), so we could test either
+ // rbp or rsi.
Label skip;
- cmpq(rdx, Immediate(StackHandler::ENTRY));
- j(equal, &skip, Label::kNear);
+ testq(rsi, rsi);
+ j(zero, &skip, Label::kNear);
movq(Operand(rbp, StandardFrameConstants::kContextOffset), rsi);
bind(&skip);
- ret(0);
+ JumpToHandlerEntry();
}
@@ -2504,11 +2523,11 @@ void MacroAssembler::ThrowUncatchable(UncatchableExceptionType type,
Register value) {
// Adjust this code if not the case.
STATIC_ASSERT(StackHandlerConstants::kSize == 5 * kPointerSize);
- STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0 * kPointerSize);
- STATIC_ASSERT(StackHandlerConstants::kContextOffset == 1 * kPointerSize);
- STATIC_ASSERT(StackHandlerConstants::kFPOffset == 2 * kPointerSize);
- STATIC_ASSERT(StackHandlerConstants::kStateOffset == 3 * kPointerSize);
- STATIC_ASSERT(StackHandlerConstants::kPCOffset == 4 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0);
+ STATIC_ASSERT(StackHandlerConstants::kCodeOffset == 1 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kStateOffset == 2 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kContextOffset == 3 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kFPOffset == 4 * kPointerSize);
// The exception is expected in rax.
if (type == OUT_OF_MEMORY) {
@@ -2538,20 +2557,23 @@ void MacroAssembler::ThrowUncatchable(UncatchableExceptionType type,
movq(rsp, Operand(rsp, StackHandlerConstants::kNextOffset));
bind(&check_kind);
- cmpq(Operand(rsp, StackHandlerConstants::kStateOffset),
- Immediate(StackHandler::ENTRY));
- j(not_equal, &fetch_next);
+ STATIC_ASSERT(StackHandler::ENTRY == 0);
+ testl(Operand(rsp, StackHandlerConstants::kStateOffset),
+ Immediate(StackHandler::KindField::kMask));
+ j(not_zero, &fetch_next);
// Set the top handler address to next handler past the top ENTRY handler.
pop(ExternalOperand(handler_address));
- // Clear the context and frame pointer (0 was saved in the handler), and
- // discard the state.
+ // Remove the code object and state, compute the handler address in rdi.
+ pop(rdi); // Code object.
+ pop(rdx); // Offset and state.
+
+ // Clear the context pointer and frame pointer (0 was saved in the handler).
pop(rsi);
pop(rbp);
- pop(rdx); // State.
- ret(0);
+ JumpToHandlerEntry();
}
« no previous file with comments | « src/x64/macro-assembler-x64.h ('k') | no next file » | no next file with comments »

Powered by Google App Engine
This is Rietveld 408576698