layers: Make PV GPA handling more consistent

Change-Id: I28d4642ca924928b9a76d6ddeb3a4e9ef106710b
diff --git a/layers/parameter_validation.cpp b/layers/parameter_validation.cpp
index 87c40ba..7f0f817 100644
--- a/layers/parameter_validation.cpp
+++ b/layers/parameter_validation.cpp
@@ -5744,36 +5744,28 @@
     }
 }
 
-static inline PFN_vkVoidFunction layer_intercept_proc(const char *name) {
-    for (unsigned int i = 0; i < sizeof(procmap) / sizeof(procmap[0]); i++) {
-        if (!strcmp(name, procmap[i].name)) return procmap[i].pFunc;
-    }
-    return NULL;
-}
-
 VKAPI_ATTR PFN_vkVoidFunction VKAPI_CALL GetDeviceProcAddr(VkDevice device, const char *funcName) {
-    assert(device);
+    const auto item = name_to_funcptr_map.find(funcName);
+    if (item != name_to_funcptr_map.end()) {
+        return reinterpret_cast<PFN_vkVoidFunction>(item->second);
+    }
 
-    PFN_vkVoidFunction addr = layer_intercept_proc(funcName);
-    if (addr) return addr;
-
-    layer_data *dev_data = GetLayerDataPtr(get_dispatch_key(device), layer_data_map);
-
-    if (!dev_data->dispatch_table.GetDeviceProcAddr) return nullptr;
-    return dev_data->dispatch_table.GetDeviceProcAddr(device, funcName);
+    layer_data *device_data = GetLayerDataPtr(get_dispatch_key(device), layer_data_map);
+    const auto &table = device_data->dispatch_table;
+    if (!table.GetDeviceProcAddr) return nullptr;
+    return table.GetDeviceProcAddr(device, funcName);
 }
 
 VKAPI_ATTR PFN_vkVoidFunction VKAPI_CALL GetInstanceProcAddr(VkInstance instance, const char *funcName) {
-
-    PFN_vkVoidFunction addr = layer_intercept_proc(funcName);
-    if (addr) return addr;
-
-    assert(instance);
+    const auto item = name_to_funcptr_map.find(funcName);
+    if (item != name_to_funcptr_map.end()) {
+        return reinterpret_cast<PFN_vkVoidFunction>(item->second);
+    }
 
     auto instance_data = GetLayerDataPtr(get_dispatch_key(instance), instance_layer_data_map);
-
-    if (!instance_data->dispatch_table.GetInstanceProcAddr) return nullptr;
-    return instance_data->dispatch_table.GetInstanceProcAddr(instance, funcName);
+    auto &table = instance_data->dispatch_table;
+    if (!table.GetInstanceProcAddr) return nullptr;
+    return table.GetInstanceProcAddr(instance, funcName);
 }
 
 VKAPI_ATTR PFN_vkVoidFunction VKAPI_CALL GetPhysicalDeviceProcAddr(VkInstance instance, const char *funcName) {
diff --git a/scripts/parameter_validation_generator.py b/scripts/parameter_validation_generator.py
index 7d3b873..eacace5 100644
--- a/scripts/parameter_validation_generator.py
+++ b/scripts/parameter_validation_generator.py
@@ -220,8 +220,8 @@
         # Output declarations and record intercepted procedures
         write('// Declarations', file=self.outFile)
         write('\n'.join(self.declarations), file=self.outFile)
-        write('// Intercepts', file=self.outFile)
-        write('struct { const char* name; PFN_vkVoidFunction pFunc;} procmap[] = {', file=self.outFile)
+        write('// Map of all APIs to be intercepted by this layer', file=self.outFile)
+        write('static const std::unordered_map<std::string, void*> name_to_funcptr_map = {', file=self.outFile)
         write('\n'.join(self.intercepts), file=self.outFile)
         write('};\n', file=self.outFile)
         self.newline()
@@ -437,7 +437,7 @@
             if (self.featureExtraProtect != None):
                 self.declarations += [ '#ifdef %s' % self.featureExtraProtect ]
                 self.intercepts += [ '#ifdef %s' % self.featureExtraProtect ]
-            self.intercepts += [ '    {"%s", reinterpret_cast<PFN_vkVoidFunction>(%s)},' % (name,name[2:]) ]
+            self.intercepts += [ '    {"%s", (void*)%s},' % (name,name[2:]) ]
             decls = self.makeCDecls(cmdinfo.elem)
             # Strip off 'vk' from API name
             self.declarations += [ '%s' % decls[0].replace("VKAPI_CALL vk", "VKAPI_CALL ") ]