MEM: Make port proxies use references rather than pointers

This patch is adding a clearer design intent to all objects that would
not be complete without a port proxy by making the proxies members
rathen than dynamically allocated. In essence, if NULL would not be a
valid value for the proxy, then we avoid using a pointer to make this
clear.

The same approach is used for the methods using these proxies, such as
loadSections, that now use references rather than pointers to better
reflect the fact that NULL would not be an acceptable value (in fact
the code would break and that is how this patch started out).

Overall the concept of "using a reference to express unconditional
composition where a NULL pointer is never valid" could be done on a
much broader scale throughout the code base, but for now it is only
done in the locations affected by the proxies.

1 files changed, 4 insertions, 4 deletions

diff --git a/src/arch/alpha/vtophys.cc b/src/arch/alpha/vtophys.cc
index 453c48444..8ca23fce2 100644
--- a/src/arch/alpha/vtophys.cc
+++ b/src/arch/alpha/vtophys.cc
@@ -45,24 +45,24 @@ using namespace std;
 namespace AlphaISA {
 
 PageTableEntry
-kernel_pte_lookup(PortProxy* mem, Addr ptbr, VAddr vaddr)
+kernel_pte_lookup(PortProxy &mem, Addr ptbr, VAddr vaddr)
 {
     Addr level1_pte = ptbr + vaddr.level1();
-    PageTableEntry level1 = mem->read<uint64_t>(level1_pte);
+    PageTableEntry level1 = mem.read<uint64_t>(level1_pte);
     if (!level1.valid()) {
         DPRINTF(VtoPhys, "level 1 PTE not valid, va = %#\n", vaddr);
         return 0;
     }
 
     Addr level2_pte = level1.paddr() + vaddr.level2();
-    PageTableEntry level2 = mem->read<uint64_t>(level2_pte);
+    PageTableEntry level2 = mem.read<uint64_t>(level2_pte);
     if (!level2.valid()) {
         DPRINTF(VtoPhys, "level 2 PTE not valid, va = %#x\n", vaddr);
         return 0;
     }
 
     Addr level3_pte = level2.paddr() + vaddr.level3();
-    PageTableEntry level3 = mem->read<uint64_t>(level3_pte);
+    PageTableEntry level3 = mem.read<uint64_t>(level3_pte);
     if (!level3.valid()) {
         DPRINTF(VtoPhys, "level 3 PTE not valid, va = %#x\n", vaddr);
         return 0;