UserspaceEmulator: Add a SoftMMU::read<T> function

...and implement SoftCPU::read_memory<T> with it. This allows the MMU to read a typed object (using 1-byte reads), which is significantly nicer to use than reading the struct fields manually.
orospakr · Mar 4, 2022 · baf7038 · baf7038
1 parent 70b53b4
commit baf7038
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Showing 3 changed files with 47 additions and 12 deletions.
diff --git a/Userland/DevTools/UserspaceEmulator/SoftCPU.h b/Userland/DevTools/UserspaceEmulator/SoftCPU.h
@@ -6,6 +6,8 @@
 
 #pragma once
 
+#include "AK/Debug.h"
+#include "Emulator.h"
 #include "Region.h"
 #include "SoftFPU.h"
 #include "ValueWithShadow.h"
@@ -367,18 +369,12 @@ class SoftCPU final
  template<typename T>
  ValueWithShadow<T> read_memory(X86::LogicalAddress address)
  {
- if constexpr (sizeof(T) == 1)
- return read_memory8(address);
- if constexpr (sizeof(T) == 2)
- return read_memory16(address);
- if constexpr (sizeof(T) == 4)
- return read_memory32(address);
- if constexpr (sizeof(T) == 8)
- return read_memory64(address);
- if constexpr (sizeof(T) == 16)
- return read_memory128(address);
- if constexpr (sizeof(T) == 32)
- return read_memory256(address);
+ auto value = m_emulator.mmu().read<T>(address);
+ if constexpr (AK::HasFormatter<T>)
+ outln_if(MEMORY_DEBUG, "\033[36;1mread_memory: @{:#04x}:{:p} -> {:#064x} ({:hex-dump})\033[0m", address.selector(), address.offset(), value.value(), value.shadow().span());
+ else
+ outln_if(MEMORY_DEBUG, "\033[36;1mread_memory: @{:#04x}:{:p} -> ??? ({:hex-dump})\033[0m", address.selector(), address.offset(), value.shadow().span());
+ return value;
  }
 
  void write_memory8(X86::LogicalAddress, ValueWithShadow<u8>);

diff --git a/Userland/DevTools/UserspaceEmulator/SoftMMU.cpp b/Userland/DevTools/UserspaceEmulator/SoftMMU.cpp
@@ -376,4 +376,9 @@ bool SoftMMU::fast_fill_memory32(X86::LogicalAddress address, size_t count, Valu
  return true;
 }
 
+void SoftMMU::dump_backtrace()
+{
+ m_emulator.dump_backtrace();
+}
+
 }
diff --git a/Userland/DevTools/UserspaceEmulator/SoftMMU.h b/Userland/DevTools/UserspaceEmulator/SoftMMU.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include "Region.h"
+#include "Report.h"
 #include "ValueWithShadow.h"
 #include <AK/HashMap.h>
 #include <AK/NonnullOwnPtrVector.h>
@@ -29,6 +30,39 @@ class SoftMMU {
  ValueWithShadow<u128> read128(X86::LogicalAddress);
  ValueWithShadow<u256> read256(X86::LogicalAddress);
 
+ void dump_backtrace();
+
+ template<typename T>
+ ValueWithShadow<T> read(X86::LogicalAddress address) requires(IsTriviallyConstructible<T>)
+ {
+ auto* region = find_region(address);
+ if (!region) {
+ reportln("SoftMMU::read256: No region for @ {:p}", address.offset());
+ dump_backtrace();
+ TODO();
+ }
+
+ if (!region->is_readable()) {
+ reportln("SoftMMU::read256: Non-readable region @ {:p}", address.offset());
+ dump_backtrace();
+ TODO();
+ }
+
+ alignas(alignof(T)) u8 data[sizeof(T)];
+ Array<u8, sizeof(T)> shadow;
+
+ for (auto i = 0u; i < sizeof(T); ++i) {
+ auto result = region->read8(address.offset() - region->base() + i);
+ data[i] = result.value();
+ shadow[i] = result.shadow()[0];
+ }
+
+ return {
+ *bit_cast<T*>(&data[0]),
+ shadow,
+ };
+ }
+
  void write8(X86::LogicalAddress, ValueWithShadow<u8>);
  void write16(X86::LogicalAddress, ValueWithShadow<u16>);
  void write32(X86::LogicalAddress, ValueWithShadow<u32>);