[common] remove ptr indirection on WallClock (#3864)

also devirtualizes manually since compiler doesn't do it with LTO

Signed-off-by: lizzie <lizzie@eden-emu.dev>

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/3864
Reviewed-by: crueter <crueter@eden-emu.dev>

1 files changed, 162 insertions, 43 deletions

diff --git a/src/common/wall_clock.cpp b/src/common/wall_clock.cpp
index 4f9c240905..bff9e7b4f4 100644
--- a/src/common/wall_clock.cpp
+++ b/src/common/wall_clock.cpp
@@ -1,77 +1,196 @@
-// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 // SPDX-FileCopyrightText: Copyright 2020 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
 #include "common/steady_clock.h"
+#include "common/uint128.h"
 #include "common/wall_clock.h"
 
+#ifdef __ANDROID__
+#include <sys/system_properties.h>
+#endif
 #ifdef ARCHITECTURE_x86_64
 #include "common/x64/cpu_detect.h"
-#include "common/x64/native_clock.h"
 #include "common/x64/rdtsc.h"
 #endif
-#ifdef HAS_NCE
-#include "common/arm64/native_clock.h"
-#endif
 
 namespace Common {
 
-class StandardWallClock final : public WallClock {
-public:
-    explicit StandardWallClock() {}
+#if defined(ARCHITECTURE_x86_64)
+WallClock::WallClock(bool invariant_, u64 rdtsc_frequency_) noexcept
+    : invariant{invariant_}
+    , rdtsc_frequency{rdtsc_frequency_}
+    , ns_rdtsc_factor{GetFixedPoint64Factor(NsRatio::den, rdtsc_frequency_)}
+    , us_rdtsc_factor{GetFixedPoint64Factor(UsRatio::den, rdtsc_frequency_)}
+    , ms_rdtsc_factor{GetFixedPoint64Factor(MsRatio::den, rdtsc_frequency_)}
+    , cntpct_rdtsc_factor{GetFixedPoint64Factor(CNTFRQ, rdtsc_frequency_)}
+    , gputick_rdtsc_factor{GetFixedPoint64Factor(GPUTickFreq, rdtsc_frequency_)}
+{}
 
-    std::chrono::nanoseconds GetTimeNS() const override {
-        return std::chrono::duration_cast<std::chrono::nanoseconds>(
-            std::chrono::system_clock::now().time_since_epoch());
-    }
+std::chrono::nanoseconds WallClock::GetTimeNS() const {
+    if (invariant)
+        return std::chrono::duration_cast<std::chrono::nanoseconds>(std::chrono::system_clock::now().time_since_epoch());
+    return std::chrono::nanoseconds{MultiplyHigh(GetUptime(), ns_rdtsc_factor)};
+}
 
-    std::chrono::microseconds GetTimeUS() const override {
-        return std::chrono::duration_cast<std::chrono::microseconds>(
-            std::chrono::system_clock::now().time_since_epoch());
-    }
+std::chrono::microseconds WallClock::GetTimeUS() const {
+    if (invariant)
+        return std::chrono::duration_cast<std::chrono::microseconds>(std::chrono::system_clock::now().time_since_epoch());
+    return std::chrono::microseconds{MultiplyHigh(GetUptime(), us_rdtsc_factor)};
+}
 
-    std::chrono::milliseconds GetTimeMS() const override {
-        return std::chrono::duration_cast<std::chrono::milliseconds>(
-            std::chrono::system_clock::now().time_since_epoch());
-    }
+std::chrono::milliseconds WallClock::GetTimeMS() const {
+    if (invariant)
+        return std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock::now().time_since_epoch());
+    return std::chrono::milliseconds{MultiplyHigh(GetUptime(), ms_rdtsc_factor)};
+}
 
-    s64 GetCNTPCT() const override {
+s64 WallClock::GetCNTPCT() const {
+    if (invariant)
         return GetUptime() * NsToCNTPCTRatio::num / NsToCNTPCTRatio::den;
-    }
+    return MultiplyHigh(GetUptime(), cntpct_rdtsc_factor);
+}
 
-    s64 GetGPUTick() const override {
+s64 WallClock::GetGPUTick() const {
+    if (invariant)
         return GetUptime() * NsToGPUTickRatio::num / NsToGPUTickRatio::den;
-    }
+    return MultiplyHigh(GetUptime(), gputick_rdtsc_factor);
+}
 
-    s64 GetUptime() const override {
-        return std::chrono::duration_cast<std::chrono::nanoseconds>(
-                   std::chrono::steady_clock::now().time_since_epoch())
-            .count();
-    }
+s64 WallClock::GetUptime() const {
+    if (invariant)
+        return std::chrono::duration_cast<std::chrono::nanoseconds>(std::chrono::steady_clock::now().time_since_epoch()).count();
+    return s64(Common::X64::FencedRDTSC());
+}
 
-    bool IsNative() const override {
+bool WallClock::IsNative() const {
+    if (invariant)
         return false;
-    }
-};
+    return true;
+}
+#elif defined(HAS_NCE)
+namespace {
 
-std::unique_ptr<WallClock> CreateOptimalClock() {
-#if defined(ARCHITECTURE_x86_64)
-    const auto& caps = GetCPUCaps();
+[[nodiscard]] WallClock::FactorType GetFixedPointFactor(u64 num, u64 den) noexcept {
+    return (WallClock::FactorType(num) << 64) / den;
+}
+
+[[nodiscard]] u64 MultiplyHigh(u64 m, WallClock::FactorType factor) noexcept {
+    return static_cast<u64>((m * factor) >> 64);
+}
 
-    if (caps.invariant_tsc && caps.tsc_frequency >= std::nano::den) {
-        return std::make_unique<X64::NativeClock>(caps.tsc_frequency);
+[[nodiscard]] s64 GetHostCNTFRQ() noexcept {
+    u64 cntfrq_el0 = 0;
+#ifdef ANDROID
+    std::string_view board{""};
+    char buffer[PROP_VALUE_MAX];
+    int len{__system_property_get("ro.product.board", buffer)};
+    board = std::string_view(buffer, static_cast<size_t>(len));
+    if (board == "s5e9925") { // Exynos 2200
+        cntfrq_el0 = 25600000;
+    } else if (board == "exynos2100") { // Exynos 2100
+        cntfrq_el0 = 26000000;
+    } else if (board == "exynos9810") { // Exynos 9810
+        cntfrq_el0 = 26000000;
+    } else if (board == "s5e8825") { // Exynos 1280
+        cntfrq_el0 = 26000000;
     } else {
-        // Fallback to StandardWallClock if the hardware TSC
-        // - Is not invariant
-        // - Is not more precise than 1 GHz (1ns resolution)
-        return std::make_unique<StandardWallClock>();
+        asm volatile("mrs %[cntfrq_el0], cntfrq_el0" : [cntfrq_el0] "=r"(cntfrq_el0));
     }
+    return cntfrq_el0;
+#else
+    asm volatile("mrs %[cntfrq_el0], cntfrq_el0" : [cntfrq_el0] "=r"(cntfrq_el0));
+    return cntfrq_el0;
+#endif
+}
+
+} // namespace
+
+WallClock::WallClock(bool invariant_, u64 rdtsc_frequency_) noexcept {
+    const u64 host_cntfrq = std::max<u64>(GetHostCNTFRQ(), 1);
+    ns_cntfrq_factor = GetFixedPointFactor(NsRatio::den, host_cntfrq);
+    us_cntfrq_factor = GetFixedPointFactor(UsRatio::den, host_cntfrq);
+    ms_cntfrq_factor = GetFixedPointFactor(MsRatio::den, host_cntfrq);
+    guest_cntfrq_factor = GetFixedPointFactor(CNTFRQ, host_cntfrq);
+    gputick_cntfrq_factor = GetFixedPointFactor(GPUTickFreq, host_cntfrq);
+}
+
+std::chrono::nanoseconds WallClock::GetTimeNS() const {
+    return std::chrono::nanoseconds{MultiplyHigh(GetUptime(), ns_cntfrq_factor)};
+}
+
+std::chrono::microseconds WallClock::GetTimeUS() const {
+    return std::chrono::microseconds{MultiplyHigh(GetUptime(), us_cntfrq_factor)};
+}
+
+std::chrono::milliseconds WallClock::GetTimeMS() const {
+    return std::chrono::milliseconds{MultiplyHigh(GetUptime(), ms_cntfrq_factor)};
+}
+
+s64 WallClock::GetCNTPCT() const {
+    return MultiplyHigh(GetUptime(), guest_cntfrq_factor);
+}
+
+s64 WallClock::GetGPUTick() const {
+    return MultiplyHigh(GetUptime(), gputick_cntfrq_factor);
+}
+
+s64 WallClock::GetUptime() const {
+    s64 cntvct_el0 = 0;
+    asm volatile(
+        "dsb ish\n\t"
+        "mrs %[cntvct_el0], cntvct_el0\n\t"
+        "dsb ish\n\t"
+        : [cntvct_el0] "=r"(cntvct_el0)
+    );
+    return cntvct_el0;
+}
+
+bool WallClock::IsNative() const {
+    return true;
+}
+#else
+WallClock::WallClock(bool invariant_, u64 rdtsc_frequency_) noexcept {}
+
+std::chrono::nanoseconds WallClock::GetTimeNS() const {
+    return std::chrono::duration_cast<std::chrono::nanoseconds>(std::chrono::system_clock::now().time_since_epoch());
+}
+
+std::chrono::microseconds WallClock::GetTimeUS() const {
+    return std::chrono::duration_cast<std::chrono::microseconds>(std::chrono::system_clock::now().time_since_epoch());
+}
+
+std::chrono::milliseconds WallClock::GetTimeMS() const {
+    return std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock::now().time_since_epoch());
+}
+
+s64 WallClock::GetCNTPCT() const {
+    return GetUptime() * NsToCNTPCTRatio::num / NsToCNTPCTRatio::den;
+}
+
+s64 WallClock::GetGPUTick() const {
+    return GetUptime() * NsToGPUTickRatio::num / NsToGPUTickRatio::den;
+}
+
+s64 WallClock::GetUptime() const {
+    return std::chrono::duration_cast<std::chrono::nanoseconds>(std::chrono::steady_clock::now().time_since_epoch()).count();
+}
+
+bool WallClock::IsNative() const {
+    return false;
+}
+#endif
+
+WallClock CreateOptimalClock() noexcept {
+#if defined(ARCHITECTURE_x86_64)
+    auto const& caps = GetCPUCaps();
+    return WallClock(!(caps.invariant_tsc && caps.tsc_frequency >= std::nano::den), std::max<u64>(caps.tsc_frequency, 1));
 #elif defined(HAS_NCE)
-    return std::make_unique<Arm64::NativeClock>();
+    return WallClock(false, 1);
 #else
-    return std::make_unique<StandardWallClock>();
+    return WallClock(true, 1);
 #endif
 }