V4: Collapse LoadRegExp+StoreReg into MoveRegExp

LoadRegExp is nearly always followed by a store of the accumulator, so
change LoadRegExp to be MoveRegExp. This saves an instruction.

Change-Id: I5d47c5bf6ffd7f28247c328410872c3b229ca23c
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

6 files changed, 16 insertions, 14 deletions

diff --git a/src/qml/compiler/qv4codegen.cpp b/src/qml/compiler/qv4codegen.cpp
index b9d223bab0..68bda2dcd3 100644
--- a/src/qml/compiler/qv4codegen.cpp
+++ b/src/qml/compiler/qv4codegen.cpp
@@ -1885,12 +1885,13 @@ bool Codegen::visit(RegExpLiteral *ast)
     if (hasError)
         return false;
 
-    auto r = Reference::fromAccumulator(this);
+    auto r = Reference::fromStackSlot(this);
     r.isReadonly = true;
     _expr.setResult(r);
 
-    Instruction::LoadRegExp instr;
+    Instruction::MoveRegExp instr;
     instr.regExpId = jsUnitGenerator->registerRegExp(ast);
+    instr.destReg = r.stackSlot();
     bytecodeGenerator->addInstruction(instr);
     return false;
 }
diff --git a/src/qml/compiler/qv4instr_moth.cpp b/src/qml/compiler/qv4instr_moth.cpp
index 9cfde99e6b..3fc8882937 100644
--- a/src/qml/compiler/qv4instr_moth.cpp
+++ b/src/qml/compiler/qv4instr_moth.cpp
@@ -261,9 +261,9 @@ void dumpBytecode(const char *code, int len, int nLocals, int nFormals, int /*st
             d << stringId;
         MOTH_END_INSTR(LoadRuntimeString)
 
-        MOTH_BEGIN_INSTR(LoadRegExp)
-            d << regExpId;
-        MOTH_END_INSTR(LoadRegExp)
+        MOTH_BEGIN_INSTR(MoveRegExp)
+            d << dumpRegister(destReg, nFormals) << ", " <<regExpId;
+        MOTH_END_INSTR(MoveRegExp)
 
         MOTH_BEGIN_INSTR(LoadClosure)
             d << value;
diff --git a/src/qml/compiler/qv4instr_moth_p.h b/src/qml/compiler/qv4instr_moth_p.h
index e0b013eb95..06cf34481c 100644
--- a/src/qml/compiler/qv4instr_moth_p.h
+++ b/src/qml/compiler/qv4instr_moth_p.h
@@ -89,7 +89,7 @@ QT_BEGIN_NAMESPACE
 #define INSTR_LoadScopedLocal(op) INSTRUCTION(op, LoadScopedLocal, 2, scope, index)
 #define INSTR_StoreScopedLocal(op) INSTRUCTION(op, StoreScopedLocal, 2, scope, index)
 #define INSTR_LoadRuntimeString(op) INSTRUCTION(op, LoadRuntimeString, 1, stringId)
-#define INSTR_LoadRegExp(op) INSTRUCTION(op, LoadRegExp, 1, regExpId)
+#define INSTR_MoveRegExp(op) INSTRUCTION(op, MoveRegExp, 2, regExpId, destReg)
 #define INSTR_LoadClosure(op) INSTRUCTION(op, LoadClosure, 1, value)
 #define INSTR_LoadName(op) INSTRUCTION(op, LoadName, 1, name)
 #define INSTR_LoadGlobalLookup(op) INSTRUCTION(op, LoadGlobalLookup, 1, index)
@@ -205,7 +205,7 @@ QT_BEGIN_NAMESPACE
     F(LoadScopedLocal) \
     F(StoreScopedLocal) \
     F(LoadRuntimeString) \
-    F(LoadRegExp) \
+    F(MoveRegExp) \
     F(LoadClosure) \
     F(LoadName) \
     F(LoadGlobalLookup) \
diff --git a/src/qml/jit/qv4jit.cpp b/src/qml/jit/qv4jit.cpp
index a8bdd20fbd..e1737cbe45 100644
--- a/src/qml/jit/qv4jit.cpp
+++ b/src/qml/jit/qv4jit.cpp
@@ -255,12 +255,13 @@ void BaselineJIT::generate_LoadRuntimeString(int stringId)
     as->loadString(stringId);
 }
 
-void BaselineJIT::generate_LoadRegExp(int regExpId)
+void BaselineJIT::generate_MoveRegExp(int regExpId, int destReg)
 {
     as->prepareCallWithArgCount(2);
     as->passInt32AsArg(regExpId, 1);
     as->passEngineAsArg(0);
     JIT_GENERATE_RUNTIME_CALL(Runtime::method_regexpLiteral, Assembler::ResultInAccumulator);
+    as->storeReg(destReg);
 }
 
 void BaselineJIT::generate_LoadClosure(int value)
@@ -1062,8 +1063,8 @@ void BaselineJIT::collectLabelsInBytecode()
         MOTH_BEGIN_INSTR(LoadRuntimeString)
         MOTH_END_INSTR(LoadRuntimeString)
 
-        MOTH_BEGIN_INSTR(LoadRegExp)
-        MOTH_END_INSTR(LoadRegExp)
+        MOTH_BEGIN_INSTR(MoveRegExp)
+        MOTH_END_INSTR(MoveRegExp)
 
         MOTH_BEGIN_INSTR(LoadClosure)
         MOTH_END_INSTR(LoadClosure)
diff --git a/src/qml/jit/qv4jit_p.h b/src/qml/jit/qv4jit_p.h
index dfa2a79c48..f9e2a9650c 100644
--- a/src/qml/jit/qv4jit_p.h
+++ b/src/qml/jit/qv4jit_p.h
@@ -137,7 +137,7 @@ public:
     void generate_LoadScopedLocal(int scope, int index) Q_DECL_OVERRIDE;
     void generate_StoreScopedLocal(int scope, int index) Q_DECL_OVERRIDE;
     void generate_LoadRuntimeString(int stringId) Q_DECL_OVERRIDE;
-    void generate_LoadRegExp(int regExpId) Q_DECL_OVERRIDE;
+    void generate_MoveRegExp(int regExpId, int destReg) Q_DECL_OVERRIDE;
     void generate_LoadClosure(int value) Q_DECL_OVERRIDE;
     void generate_LoadName(int name) Q_DECL_OVERRIDE;
     void generate_LoadGlobalLookup(int index) Q_DECL_OVERRIDE;
diff --git a/src/qml/jsruntime/qv4vme_moth.cpp b/src/qml/jsruntime/qv4vme_moth.cpp
index adf43812cf..59cfc5f075 100644
--- a/src/qml/jsruntime/qv4vme_moth.cpp
+++ b/src/qml/jsruntime/qv4vme_moth.cpp
@@ -652,9 +652,9 @@ QV4::ReturnedValue VME::exec(const FunctionObject *fo, const Value *thisObject,
         acc = function->compilationUnit->runtimeStrings[stringId]->asReturnedValue();
     MOTH_END_INSTR(LoadRuntimeString)
 
-    MOTH_BEGIN_INSTR(LoadRegExp)
-        acc = Runtime::method_regexpLiteral(engine, regExpId);
-    MOTH_END_INSTR(LoadRegExp)
+    MOTH_BEGIN_INSTR(MoveRegExp)
+        STACK_VALUE(destReg) = Runtime::method_regexpLiteral(engine, regExpId);
+    MOTH_END_INSTR(MoveRegExp)
 
     MOTH_BEGIN_INSTR(LoadClosure)
         acc = Runtime::method_closure(engine, value);