Merge commit '6e19bb560d474736d45f5be011ff0830c7019991' as 'spasm'

1 files changed, 130 insertions, 0 deletions

diff --git a/spasm/src/frames.cpp b/spasm/src/frames.cpp
new file mode 100644
index 0000000..8b7c891
--- /dev/null
+++ b/spasm/src/frames.cpp
@@ -0,0 +1,130 @@
+#include <algorithm>
+
+#include "types.hpp"
+
+#include "frames.hpp"
+
+namespace SpasmImpl
+{
+FrameStack::FrameStack() : base_ptr(NULL), frame_ptr(NULL), g_size(0), c_size(0)
+{
+}
+
+FrameStack::FrameStack(const FrameStack& fs)
+    : g_size(fs.g_size), c_size(fs.c_size), fstack(fs.fstack)
+{
+    copy_fstack(fs);
+}
+
+FrameStack::~FrameStack()
+{
+    delete_fstack();
+}
+
+FrameStack& FrameStack::operator=(const FrameStack& fs)
+{
+    if (this != &fs)
+    {
+        delete_fstack();
+        copy_fstack(fs);
+        g_size = fs.g_size;
+        c_size = fs.c_size;
+        fstack = fs.fstack;
+    }
+    return *this;
+}
+
+/*!
+** Deletes the frame stack
+*/
+void FrameStack::delete_fstack()
+{
+    if (base_ptr)
+        delete[] base_ptr;
+}
+
+/*!
+** Copies the frame stack fs
+**
+** \param fs - the frame stack to be copied
+*/
+void FrameStack::copy_fstack(const FrameStack& fs)
+{
+    base_ptr = new data_t[fs.g_size];
+    std::copy(fs.base_ptr, fs.frame_ptr + fs.c_size, base_ptr);
+    frame_ptr = base_ptr + (fs.frame_ptr - fs.base_ptr);
+}
+
+/*!
+** Returns a data_t object from the current frame
+**
+** \param index - index of the data_t object
+** \return const reference to the object
+*/
+const data_t& FrameStack::operator[](size_t index) const
+{
+    return frame_ptr[index];
+}
+
+/*!
+** Returns a data_t object from the current frame
+**
+** \param index - index of the data_t object
+** \return reference to the object
+*/
+data_t& FrameStack::operator[](size_t index)
+{
+    return frame_ptr[index];
+}
+
+/*!
+** Removes the current frame from the stack.
+** It is called when a function does return.
+*/
+void FrameStack::pop_frame()
+{
+    if (fstack.empty())
+    {
+        frame_ptr = base_ptr;
+        c_size = 0;
+    }
+    else
+    {
+        data_t* new_frame_ptr = base_ptr + fstack.top();
+        fstack.pop();
+        c_size = frame_ptr - new_frame_ptr;
+        frame_ptr = new_frame_ptr;
+    }
+}
+
+/*!
+** Creates (pushes on the stack) new frame of fsize data_t objects
+**
+** \param fsize - size in data_t objects of the new frame
+*/
+void FrameStack::new_frame(size_t fsize)
+{
+    if (frame_ptr + c_size + fsize > base_ptr + g_size)
+    {
+        size_t new_size = g_size + std::max(g_size, c_size + fsize);
+        data_t* new_base = new data_t[new_size];
+        if (base_ptr)
+        {
+            std::copy(base_ptr, frame_ptr + c_size, new_base);
+            delete[] base_ptr;
+        }
+        frame_ptr = new_base + (frame_ptr - base_ptr);
+        base_ptr = new_base;
+    }
+    fstack.push(frame_ptr - base_ptr);
+    c_size = fsize;
+}
+
+/*!
+** \return true if the stack is empty
+*/
+bool FrameStack::empty() const
+{
+    return frame_ptr == base_ptr && c_size == 0;
+}
+}  // namespace SpasmImpl