diff options
author | Lars Knoll <lars.knoll@qt.io> | 2018-06-01 12:21:08 +0200 |
---|---|---|
committer | Simon Hausmann <simon.hausmann@qt.io> | 2018-06-21 12:27:21 +0000 |
commit | 267513e6d955cb93abb879c495dd079c254d3493 (patch) | |
tree | 8cd3bd26756142b80b9e12f77e8b3e7e868be35b /src/qml/compiler/qv4bytecodegenerator_p.h | |
parent | 93a70a051b21ae253331f922027bd9bb7a3e457a (diff) |
Rework unwind handling
The old code was rather convoluted and expanded to quite
a bit of bytecode. It was also very hard to fix some
of the remaining issues with unwinding in there.
The new code handles unwinding a bit differently. Basically,
we now have three instructions to do what the spec requires.
SetUnwindHandler is the same as the old SetExceptionHandler
instruction. It basically tells the runtime where to jump to
to handle any abrupt completion (ie. throw/break/continue/return)
that requires unwinding.
UnwindToLabel is a new instruction that is used for unwinding
break/continue/return statements. It takes two arguments, one
telling the runtime how many levels to unwind and the second
a target label to jump to when unwinding is done.
UnwindDispatch is the third instruction and is invoked at
the end of each unwind block to dispatch the the parent
unwind handler if required and thus implement the support
for the levelled unwinding.
Change-Id: I079a39d0d897b3ecc2f0dc631ca29b25eae05250
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>
Diffstat (limited to 'src/qml/compiler/qv4bytecodegenerator_p.h')
-rw-r--r-- | src/qml/compiler/qv4bytecodegenerator_p.h | 44 |
1 files changed, 20 insertions, 24 deletions
diff --git a/src/qml/compiler/qv4bytecodegenerator_p.h b/src/qml/compiler/qv4bytecodegenerator_p.h index b12584d41f..78ce3624ea 100644 --- a/src/qml/compiler/qv4bytecodegenerator_p.h +++ b/src/qml/compiler/qv4bytecodegenerator_p.h @@ -81,14 +81,6 @@ public: if (mode == LinkNow) link(); } - static Label returnLabel() { - Label l; - l.index = INT_MAX; - return l; - } - bool isReturn() const { - return index == INT_MAX; - } void link() { Q_ASSERT(index >= 0); @@ -96,6 +88,7 @@ public: generator->labels[index] = generator->instructions.size(); generator->clearLastInstruction(); } + bool isValid() const { return generator != nullptr; } BytecodeGenerator *generator = nullptr; int index = -1; @@ -192,6 +185,12 @@ public: return addJumpInstruction(data); } + Q_REQUIRED_RESULT Jump jumpNoException() + { + Instruction::JumpNoException data; + return addJumpInstruction(data); + } + void jumpStrictEqual(const StackSlot &lhs, const Label &target) { Instruction::CmpStrictEqual cmp; @@ -208,22 +207,6 @@ public: addJumpInstruction(Instruction::JumpTrue()).link(target); } - Q_REQUIRED_RESULT Jump jumpStrictEqualStackSlotInt(const StackSlot &lhs, int rhs) - { - Instruction::JumpStrictEqualStackSlotInt data; - data.lhs = lhs; - data.rhs = rhs; - return addJumpInstruction(data); - } - - Q_REQUIRED_RESULT Jump jumpStrictNotEqualStackSlotInt(const StackSlot &lhs, int rhs) - { - Instruction::JumpStrictNotEqualStackSlotInt data; - data.lhs = lhs; - data.rhs = rhs; - return addJumpInstruction(data); - } - void setUnwindHandler(ExceptionHandler *handler) { currentExceptionHandler = handler; @@ -235,6 +218,19 @@ public: addJumpInstruction(data).link(*handler); } + void unwindToLabel(int level, const Label &target) + { + if (level) { + Instruction::UnwindToLabel unwind; + unwind.level = level; + addJumpInstruction(unwind).link(target); + } else { + jump().link(target); + } + } + + + void setLocation(const QQmlJS::AST::SourceLocation &loc); ExceptionHandler *exceptionHandler() const { |