IOS LLE: checkpoint NAND conformance and diagnostic tooling

Preserve formatted NAND boot and Wii Remote pairing, add DMA/SRAM conformance tests and a Wii comparison probe. Keep P1 profiling tools and native update A/B evidence; reject the unhelpful targeted SRAM shortcut.

Source/UnitTests/Common/PerformanceTraceTest.cpp

@@ -0,0 +1,56 @@
+// Copyright 2026 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include "Common/PerformanceTrace.h"
+#include <gtest/gtest.h>
+
+using namespace Common::PerformanceTrace;
+TEST(PerformanceTrace, NestedTimesAreExclusive)
+{
+  ScopeStack stack;
+  ASSERT_TRUE(stack.Begin(Region::Slice, 100));
+  ASSERT_TRUE(stack.Begin(Region::ARM, 110));
+  ASSERT_TRUE(stack.Begin(Region::Journal, 120));
+  ASSERT_TRUE(stack.End(150));
+  ASSERT_TRUE(stack.End(180));
+  ASSERT_TRUE(stack.End(200));
+  const auto& t = stack.Timings();
+  EXPECT_EQ(t[static_cast<size_t>(Region::Slice)].inclusive, 100u);
+  EXPECT_EQ(t[static_cast<size_t>(Region::Slice)].exclusive, 30u);
+  EXPECT_EQ(t[static_cast<size_t>(Region::ARM)].exclusive, 40u);
+  EXPECT_EQ(t[static_cast<size_t>(Region::Journal)].exclusive, 30u);
+  EXPECT_EQ(stack.Errors(), 0u);
+  EXPECT_EQ(stack.Depth(), 0u);
+}
+TEST(PerformanceTrace, RecursiveRegionAndReset)
+{
+  ScopeStack stack;
+  ASSERT_TRUE(stack.Begin(Region::ARM, 0));
+  ASSERT_TRUE(stack.Begin(Region::ARM, 10));
+  ASSERT_TRUE(stack.End(20));
+  ASSERT_TRUE(stack.End(30));
+  EXPECT_EQ(stack.Timings()[static_cast<size_t>(Region::ARM)].exclusive, 30u);
+  EXPECT_EQ(stack.Timings()[static_cast<size_t>(Region::ARM)].calls, 2u);
+  stack.Reset();
+  EXPECT_EQ(stack.Timings()[static_cast<size_t>(Region::ARM)].calls, 0u);
+  EXPECT_EQ(stack.Depth(), 0u);
+}
+TEST(PerformanceTrace, InvalidClockAndUnderflowAreReported)
+{
+  ScopeStack stack;
+  EXPECT_FALSE(stack.End(0));
+  ASSERT_TRUE(stack.Begin(Region::ARM, 100));
+  EXPECT_FALSE(stack.End(99));
+  EXPECT_EQ(stack.Errors(), 2u);
+  EXPECT_EQ(stack.Timings()[static_cast<size_t>(Region::ARM)].inclusive, 0u);
+}
+TEST(PerformanceTrace, DepthOverflowIsBounded)
+{
+  ScopeStack stack;
+  for (u64 i = 0; i < 32; ++i)
+    ASSERT_TRUE(stack.Begin(Region::ARM, i));
+  EXPECT_FALSE(stack.Begin(Region::ARM, 32));
+  for (u64 i = 0; i < 32; ++i)
+    ASSERT_TRUE(stack.End(40 + i));
+  EXPECT_EQ(stack.Depth(), 0u);
+  EXPECT_EQ(stack.Errors(), 1u);
+}