Revision: 8936
Author: [email protected]
Date: Tue Aug 16 01:48:45 2011
Log: MIPS: port Simplify handling of exits from with and catch.
Ported r8922 (5ea2fb5)
Original commit message:
Remove the try/finally used for with and catch. Instead of using
try/finally to handle break and continue from with or catch,
statically track nesting dept and clean up when compiling break or
continue.
And instead of using try/finally to handle throw to handler in a frame
whose pc is inside a with or catch, store the context that the handler
should run in in the handler itself.
BUG=
TEST=
Review URL: http://codereview.chromium.org/7648026
Patch from Paul Lind <[email protected]>.
http://code.google.com/p/v8/source/detail?r=8936
Modified:
/branches/bleeding_edge/src/mips/frames-mips.h
/branches/bleeding_edge/src/mips/macro-assembler-mips.cc
=======================================
--- /branches/bleeding_edge/src/mips/frames-mips.h Tue May 24 00:23:32 2011
+++ /branches/bleeding_edge/src/mips/frames-mips.h Tue Aug 16 01:48:45 2011
@@ -121,10 +121,11 @@
class StackHandlerConstants : public AllStatic {
public:
- static const int kNextOffset = 0 * kPointerSize;
- static const int kStateOffset = 1 * kPointerSize;
- static const int kFPOffset = 2 * kPointerSize;
- static const int kPCOffset = 3 * kPointerSize;
+ static const int kNextOffset = 0 * kPointerSize;
+ static const int kStateOffset = 1 * kPointerSize;
+ static const int kContextOffset = 2 * kPointerSize;
+ static const int kFPOffset = 3 * kPointerSize;
+ static const int kPCOffset = 4 * kPointerSize;
static const int kSize = kPCOffset + kPointerSize;
};
=======================================
--- /branches/bleeding_edge/src/mips/macro-assembler-mips.cc Wed Jul 20
00:24:50 2011
+++ /branches/bleeding_edge/src/mips/macro-assembler-mips.cc Tue Aug 16
01:48:45 2011
@@ -2244,7 +2244,13 @@
void MacroAssembler::PushTryHandler(CodeLocation try_location,
HandlerType type) {
// Adjust this code if not the case.
- ASSERT(StackHandlerConstants::kSize == 4 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kSize == 5 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kStateOffset == 1 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kContextOffset == 2 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kFPOffset == 3 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kPCOffset == 4 * kPointerSize);
+
// The return address is passed in register ra.
if (try_location == IN_JAVASCRIPT) {
if (type == TRY_CATCH_HANDLER) {
@@ -2252,19 +2258,16 @@
} else {
li(t0, Operand(StackHandler::TRY_FINALLY));
}
- ASSERT(StackHandlerConstants::kStateOffset == 1 * kPointerSize
- && StackHandlerConstants::kFPOffset == 2 * kPointerSize
- && StackHandlerConstants::kPCOffset == 3 * kPointerSize
- && StackHandlerConstants::kNextOffset == 0 * kPointerSize);
// Save the current handler as the next handler.
li(t2, Operand(ExternalReference(Isolate::k_handler_address,
isolate())));
lw(t1, MemOperand(t2));
addiu(sp, sp, -StackHandlerConstants::kSize);
- sw(ra, MemOperand(sp, 12));
- sw(fp, MemOperand(sp, 8));
- sw(t0, MemOperand(sp, 4));
- sw(t1, MemOperand(sp, 0));
+ sw(ra, MemOperand(sp, StackHandlerConstants::kPCOffset));
+ sw(fp, MemOperand(sp, StackHandlerConstants::kFPOffset));
+ sw(cp, MemOperand(sp, StackHandlerConstants::kContextOffset));
+ sw(t0, MemOperand(sp, StackHandlerConstants::kStateOffset));
+ sw(t1, MemOperand(sp, StackHandlerConstants::kNextOffset));
// Link this handler as the new current one.
sw(sp, MemOperand(t2));
@@ -2272,11 +2275,6 @@
} else {
// Must preserve a0-a3, and s0 (argv).
ASSERT(try_location == IN_JS_ENTRY);
- ASSERT(StackHandlerConstants::kStateOffset == 1 * kPointerSize
- && StackHandlerConstants::kFPOffset == 2 * kPointerSize
- && StackHandlerConstants::kPCOffset == 3 * kPointerSize
- && StackHandlerConstants::kNextOffset == 0 * kPointerSize);
-
// The frame pointer does not point to a JS frame so we save NULL
// for fp. We expect the code throwing an exception to check fp
// before dereferencing it to restore the context.
@@ -2286,11 +2284,14 @@
li(t2, Operand(ExternalReference(Isolate::k_handler_address,
isolate())));
lw(t1, MemOperand(t2));
+ ASSERT(Smi::FromInt(0) == 0); // Used for no context.
+
addiu(sp, sp, -StackHandlerConstants::kSize);
- sw(ra, MemOperand(sp, 12));
- sw(zero_reg, MemOperand(sp, 8));
- sw(t0, MemOperand(sp, 4));
- sw(t1, MemOperand(sp, 0));
+ sw(ra, MemOperand(sp, StackHandlerConstants::kPCOffset));
+ sw(zero_reg, MemOperand(sp, StackHandlerConstants::kFPOffset));
+ sw(zero_reg, MemOperand(sp, StackHandlerConstants::kContextOffset));
+ sw(t0, MemOperand(sp, StackHandlerConstants::kStateOffset));
+ sw(t1, MemOperand(sp, StackHandlerConstants::kNextOffset));
// Link this handler as the new current one.
sw(sp, MemOperand(t2));
@@ -2299,7 +2300,7 @@
void MacroAssembler::PopTryHandler() {
- ASSERT_EQ(0, StackHandlerConstants::kNextOffset);
+ STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0);
pop(a1);
Addu(sp, sp, Operand(StackHandlerConstants::kSize - kPointerSize));
li(at, Operand(ExternalReference(Isolate::k_handler_address,
isolate())));
@@ -2312,28 +2313,31 @@
Move(v0, value);
// Adjust this code if not the case.
- STATIC_ASSERT(StackHandlerConstants::kSize == 4 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kSize == 5 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kStateOffset == 1 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kContextOffset == 2 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kFPOffset == 3 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kPCOffset == 4 * kPointerSize);
// Drop the sp to the top of the handler.
li(a3, Operand(ExternalReference(Isolate::k_handler_address,
- isolate())));
+ isolate())));
lw(sp, MemOperand(a3));
- // Restore the next handler and frame pointer, discard handler state.
- STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0);
+ // Restore the next handler.
pop(a2);
sw(a2, MemOperand(a3));
- STATIC_ASSERT(StackHandlerConstants::kFPOffset == 2 * kPointerSize);
- MultiPop(a3.bit() | fp.bit());
-
- // Before returning we restore the context from the frame pointer if
- // not NULL. The frame pointer is NULL in the exception handler of a
- // JS entry frame.
- // Set cp to NULL if fp is NULL.
+
+ // Restore context and frame pointer, discard state (a3).
+ MultiPop(a3.bit() | cp.bit() | fp.bit());
+
+ // If the handler is a JS frame, restore the context to the frame.
+ // (a3 == ENTRY) == (fp == 0) == (cp == 0), so we could test any
+ // of them.
Label done;
- Branch(USE_DELAY_SLOT, &done, eq, fp, Operand(zero_reg));
- mov(cp, zero_reg); // In branch delay slot.
- lw(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
+ Branch(&done, eq, fp, Operand(zero_reg));
+ sw(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
bind(&done);
#ifdef DEBUG
@@ -2355,7 +2359,6 @@
}
#endif
- STATIC_ASSERT(StackHandlerConstants::kPCOffset == 3 * kPointerSize);
pop(t9); // 2 instructions: lw, add sp.
Jump(t9); // 2 instructions: jr, nop (in delay slot).
@@ -2370,7 +2373,12 @@
void MacroAssembler::ThrowUncatchable(UncatchableExceptionType type,
Register value) {
// Adjust this code if not the case.
- STATIC_ASSERT(StackHandlerConstants::kSize == 4 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kSize == 5 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kStateOffset == 1 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kContextOffset == 2 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kFPOffset == 3 * kPointerSize);
+ STATIC_ASSERT(StackHandlerConstants::kPCOffset == 4 * kPointerSize);
// v0 is expected to hold the exception.
Move(v0, value);
@@ -2393,7 +2401,6 @@
bind(&done);
// Set the top handler address to next handler past the current ENTRY
handler.
- STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0);
pop(a2);
sw(a2, MemOperand(a3));
@@ -2415,20 +2422,12 @@
// Stack layout at this point. See also StackHandlerConstants.
// sp -> state (ENTRY)
+ // cp
// fp
// ra
- // Discard handler state (a2 is not used) and restore frame pointer.
- STATIC_ASSERT(StackHandlerConstants::kFPOffset == 2 * kPointerSize);
- MultiPop(a2.bit() | fp.bit()); // a2: discarded state.
- // Before returning we restore the context from the frame pointer if
- // not NULL. The frame pointer is NULL in the exception handler of a
- // JS entry frame.
- Label cp_null;
- Branch(USE_DELAY_SLOT, &cp_null, eq, fp, Operand(zero_reg));
- mov(cp, zero_reg); // In the branch delay slot.
- lw(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
- bind(&cp_null);
+ // Restore context and frame pointer, discard state (r2).
+ MultiPop(a2.bit() | cp.bit() | fp.bit());
#ifdef DEBUG
// When emitting debug_code, set ra as return address for the jump.
@@ -2448,7 +2447,6 @@
addiu(ra, ra, kOffsetRaBytes);
}
#endif
- STATIC_ASSERT(StackHandlerConstants::kPCOffset == 3 * kPointerSize);
pop(t9); // 2 instructions: lw, add sp.
Jump(t9); // 2 instructions: jr, nop (in delay slot).
--
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