Put PushArgument into the environment instead of raw values.

runtime/vm/flow_graph_compiler_ia32.cc

Index: runtime/vm/flow_graph_compiler_ia32.cc
diff --git a/runtime/vm/flow_graph_compiler_ia32.cc b/runtime/vm/flow_graph_compiler_ia32.cc
index f33c0513a952924afb728eae8ea504b2ae8ae0d5..be09e6dc030fb19f78b9e6ed2dd1edd5c164168f 100644
--- a/runtime/vm/flow_graph_compiler_ia32.cc
+++ b/runtime/vm/flow_graph_compiler_ia32.cc
@@ -46,13 +46,20 @@ void DeoptimizationStub::GenerateCode(FlowGraphCompiler* compiler,
     const GrowableArray<Value*>& values = deoptimization_env_->values();
 
     // 1. Build a parallel move representing the frame translation.
+    intptr_t height = compiler->StackSize();
     ParallelMoveInstr* move = new ParallelMoveInstr();
     for (intptr_t i = 0; i < values.length(); i++) {
       Location destination = Location::StackSlot(i - fixed_parameter_count);
       Location source = deoptimization_env_->LocationAt(i);
       if (source.IsInvalid()) {
-        ASSERT(values[i]->IsConstant());
-        source = Location::Constant(values[i]->AsConstant()->value());
+        Value* value = values[i];
+        if (value->IsConstant()) {
+          source = Location::Constant(value->AsConstant()->value());
+        } else {
+          ASSERT(value->IsUse() &&
+                 value->AsUse()->definition()->IsPushArgument());
+          source = Location::StackSlot(height++);
+        }
       }
       move->AddMove(destination, source);
     }
@@ -62,6 +69,20 @@ void DeoptimizationStub::GenerateCode(FlowGraphCompiler* compiler,
     const intptr_t top_offset =
         ParsedFunction::kFirstLocalSlotIndex - (local_slot_count - 1);
 
+#if defined(DEBUG)
+    intptr_t optimized_top_offset =
+        (ParsedFunction::kFirstLocalSlotIndex - height) * kWordSize;
+    Label height_ok;
+    __ pushl(EAX);
+    __ leal(EAX, Address(EBP, optimized_top_offset));
+    __ cmpl(EAX, ESP);
+    // Some instructions might push temporary values above an optimized frame.
+    __ j(ABOVE_EQUAL, &height_ok);
+    __ Stop("Optimized frame height mismatch");
+    __ Bind(&height_ok);
+    __ popl(EAX);
+#endif
+
     // ParallelMoveResolver will use push and pop to allocate internally a
     // scratch register for memory to memory moves.  This means we have to
     // ensure that these stack manipulations will not interfere with actual
@@ -70,16 +91,14 @@ void DeoptimizationStub::GenerateCode(FlowGraphCompiler* compiler,
     // we need to shrink stack area after resolving parallel move. This
     // guarantees that all moves happen below stack pointer and will not
     // interfere with additional push/pops.
-    const intptr_t spill_slot_count = compiler->StackSize();
-
-    if (local_slot_count > spill_slot_count) {
+    if (local_slot_count >= height) {
       // Expand reserved stack area.
       __ leal(ESP, Address(EBP, top_offset * kWordSize));
     }
 
     compiler->parallel_move_resolver()->EmitNativeCode(move);
 
-    if (local_slot_count < spill_slot_count) {
+    if (local_slot_count < height) {
       // Shrink reserved stack area.
       __ leal(ESP, Address(EBP, top_offset * kWordSize));
     }