UserspaceEmulator: Remove hand-rolled is_foo() helpers in favor of RTTI

Author: https://github.com/awesomekling
Commit: https://github.com/SerenityOS/serenity/commit/febc8a5ac70

DevTools/UserspaceEmulator/Emulator.cpp

@@ -280,7 +280,7 @@ const MmapRegion* Emulator::find_text_region(FlatPtr address)
 {
     const MmapRegion* matching_region = nullptr;
     mmu().for_each_region([&](auto& region) {
-        if (!region.is_mmap())
+        if (!is<MmapRegion>(region))
             return IterationDecision::Continue;
         const auto& mmap_region = static_cast<const MmapRegion&>(region);
         if (!(mmap_region.is_executable() && address >= mmap_region.base() && address < mmap_region.base() + mmap_region.size()))
@@ -1045,7 +1045,7 @@ FlatPtr Emulator::virt$mremap(FlatPtr params_addr)
     mmu().copy_from_vm(&params, params_addr, sizeof(params));
 
     if (auto* region = mmu().find_region({ m_cpu.ds(), params.old_address })) {
-        if (!region->is_mmap())
+        if (!is<MmapRegion>(*region))
             return -EINVAL;
         ASSERT(region->size() == params.old_size);
         auto& mmap_region = *(MmapRegion*)region;
@@ -1094,7 +1094,7 @@ u32 Emulator::virt$unveil(u32)
 u32 Emulator::virt$mprotect(FlatPtr base, size_t size, int prot)
 {
     if (auto* region = mmu().find_region({ m_cpu.ds(), base })) {
-        if (!region->is_mmap())
+        if (!is<MmapRegion>(*region))
             return -EINVAL;
         ASSERT(region->size() == size);
         auto& mmap_region = *(MmapRegion*)region;

DevTools/UserspaceEmulator/MallocTracer.cpp

@@ -45,7 +45,7 @@ template<typename Callback>
 inline void MallocTracer::for_each_mallocation(Callback callback) const
 {
     m_emulator.mmu().for_each_region([&](auto& region) {
-        if (region.is_mmap() && static_cast<const MmapRegion&>(region).is_malloc_block()) {
+        if (is<MmapRegion>(region) && static_cast<const MmapRegion&>(region).is_malloc_block()) {
             auto* malloc_data = static_cast<MmapRegion&>(region).malloc_metadata();
             for (auto& mallocation : malloc_data->mallocations) {
                 if (mallocation.used && callback(mallocation) == IterationDecision::Break)
@@ -62,7 +62,7 @@ void MallocTracer::target_did_malloc(Badge<SoftCPU>, FlatPtr address, size_t siz
         return;
     auto* region = m_emulator.mmu().find_region({ 0x23, address });
     ASSERT(region);
-    ASSERT(region->is_mmap());
+    ASSERT(is<MmapRegion>(*region));
     auto& mmap_region = static_cast<MmapRegion&>(*region);
 
     // Mark the containing mmap region as a malloc block!
@@ -145,7 +145,7 @@ void MallocTracer::target_did_realloc(Badge<SoftCPU>, FlatPtr address, size_t si
         return;
     auto* region = m_emulator.mmu().find_region({ 0x23, address });
     ASSERT(region);
-    ASSERT(region->is_mmap());
+    ASSERT(is<MmapRegion>(*region));
     auto& mmap_region = static_cast<MmapRegion&>(*region);
 
     ASSERT(mmap_region.is_malloc_block());
@@ -334,7 +334,7 @@ bool MallocTracer::is_reachable(const Mallocation& mallocation) const
         if (!region.is_readable())
             return IterationDecision::Continue;
         // Skip malloc blocks
-        if (region.is_mmap() && static_cast<const MmapRegion&>(region).is_malloc_block())
+        if (is<MmapRegion>(region) && static_cast<const MmapRegion&>(region).is_malloc_block())
             return IterationDecision::Continue;
 
         size_t pointers_in_region = region.size() / sizeof(u32);

DevTools/UserspaceEmulator/MallocTracer.h

@@ -95,7 +95,7 @@ private:
 
 ALWAYS_INLINE Mallocation* MallocTracer::find_mallocation(const Region& region, FlatPtr address)
 {
-    if (!region.is_mmap())
+    if (!is<MmapRegion>(region))
         return nullptr;
     if (!static_cast<const MmapRegion&>(region).is_malloc_block())
         return nullptr;

DevTools/UserspaceEmulator/MmapRegion.h

@@ -65,7 +65,6 @@ public:
 
 private:
     MmapRegion(u32 base, u32 size, int prot);
-    virtual bool is_mmap() const override { return true; }
 
     u8* m_data { nullptr };
     u8* m_shadow_data { nullptr };

DevTools/UserspaceEmulator/Region.h

@@ -27,6 +27,7 @@
 #pragma once
 
 #include "ValueWithShadow.h"
+#include <AK/TypeCasts.h>
 #include <AK/Types.h>
 
 namespace UserspaceEmulator {
@@ -54,8 +55,6 @@ public:
     virtual ValueWithShadow<u64> read64(u32 offset) = 0;
 
     virtual u8* cacheable_ptr([[maybe_unused]] u32 offset) { return nullptr; }
-    virtual bool is_shared_buffer() const { return false; }
-    virtual bool is_mmap() const { return false; }
 
     bool is_stack() const { return m_stack; }
     void set_stack(bool b) { m_stack = b; }

DevTools/UserspaceEmulator/SharedBufferRegion.h

@@ -49,8 +49,6 @@ public:
     virtual u8* data() override { return m_data; }
     virtual u8* shadow_data() override { return m_shadow_data; }
 
-    bool is_shared_buffer() const override { return true; }
-
     int shbuf_id() const { return m_shbuf_id; }
 
     int allow_all();

DevTools/UserspaceEmulator/SoftMMU.cpp

@@ -44,7 +44,7 @@ void SoftMMU::add_region(NonnullOwnPtr<Region> region)
     ASSERT(!find_region({ 0x23, region->base() }));
 
     // FIXME: More sanity checks pls
-    if (region->is_shared_buffer())
+    if (is<SharedBufferRegion>(*region))
         m_shbuf_regions.set(static_cast<SharedBufferRegion*>(region.ptr())->shbuf_id(), region.ptr());
 
     size_t first_page_in_region = region->base() / PAGE_SIZE;
@@ -63,7 +63,7 @@ void SoftMMU::remove_region(Region& region)
         m_page_to_region_map[first_page_in_region + i] = nullptr;
     }
 
-    if (region.is_shared_buffer())
+    if (is<SharedBufferRegion>(region))
         m_shbuf_regions.remove(static_cast<SharedBufferRegion&>(region).shbuf_id());
     m_regions.remove_first_matching([&](auto& entry) { return entry.ptr() == &region; });
 }
@@ -253,7 +253,7 @@ bool SoftMMU::fast_fill_memory8(X86::LogicalAddress address, size_t size, ValueW
     if (!region->contains(address.offset() + size - 1))
         return false;
 
-    if (region->is_mmap() && static_cast<const MmapRegion&>(*region).is_malloc_block()) {
+    if (is<MmapRegion>(*region) && static_cast<const MmapRegion&>(*region).is_malloc_block()) {
         if (auto* tracer = m_emulator.malloc_tracer()) {
             // FIXME: Add a way to audit an entire range of memory instead of looping here!
             for (size_t i = 0; i < size; ++i) {
@@ -278,7 +278,7 @@ bool SoftMMU::fast_fill_memory32(X86::LogicalAddress address, size_t count, Valu
     if (!region->contains(address.offset() + (count * sizeof(u32)) - 1))
         return false;
 
-    if (region->is_mmap() && static_cast<const MmapRegion&>(*region).is_malloc_block()) {
+    if (is<MmapRegion>(*region) && static_cast<const MmapRegion&>(*region).is_malloc_block()) {
         if (auto* tracer = m_emulator.malloc_tracer()) {
             // FIXME: Add a way to audit an entire range of memory instead of looping here!
             for (size_t i = 0; i < count; ++i) {