7 files changed, 298 insertions, 452 deletions

diff --git a/src/common/CMakeLists.txt b/src/common/CMakeLists.txt
index 7f3712efa..2be6fe996 100644
--- a/src/common/CMakeLists.txt
+++ b/src/common/CMakeLists.txt
@@ -24,6 +24,7 @@ set(SRCS
 set(HEADERS
             assert.h
             bit_field.h
+            bit_set.h
             break_points.h
             chunk_file.h
             code_block.h
diff --git a/src/common/bit_set.h b/src/common/bit_set.h
new file mode 100644
index 000000000..85f91e786
--- /dev/null
+++ b/src/common/bit_set.h
@@ -0,0 +1,189 @@
+// This file is under the public domain.
+
+#pragma once
+
+#include <cstddef>
+#ifdef _WIN32
+#include <intrin.h>
+#endif
+#include <initializer_list>
+#include <type_traits>
+#include "common/common_types.h"
+
+// namespace avoids conflict with OS X Carbon; don't use BitSet<T> directly
+namespace Common {
+
+// Helper functions:
+
+#ifdef _WIN32
+template <typename T>
+static inline int CountSetBits(T v)
+{
+    // from https://graphics.stanford.edu/~seander/bithacks.html
+    // GCC has this built in, but MSVC's intrinsic will only emit the actual
+    // POPCNT instruction, which we're not depending on
+    v = v - ((v >> 1) & (T)~(T)0/3);
+    v = (v & (T)~(T)0/15*3) + ((v >> 2) & (T)~(T)0/15*3);
+    v = (v + (v >> 4)) & (T)~(T)0/255*15;
+    return (T)(v * ((T)~(T)0/255)) >> (sizeof(T) - 1) * 8;
+}
+static inline int LeastSignificantSetBit(u8 val)
+{
+    unsigned long index;
+    _BitScanForward(&index, val);
+    return (int)index;
+}
+static inline int LeastSignificantSetBit(u16 val)
+{
+    unsigned long index;
+    _BitScanForward(&index, val);
+    return (int)index;
+}
+static inline int LeastSignificantSetBit(u32 val)
+{
+    unsigned long index;
+    _BitScanForward(&index, val);
+    return (int)index;
+}
+static inline int LeastSignificantSetBit(u64 val)
+{
+    unsigned long index;
+    _BitScanForward64(&index, val);
+    return (int)index;
+}
+#else
+static inline int CountSetBits(u8 val) { return __builtin_popcount(val); }
+static inline int CountSetBits(u16 val) { return __builtin_popcount(val); }
+static inline int CountSetBits(u32 val) { return __builtin_popcount(val); }
+static inline int CountSetBits(u64 val) { return __builtin_popcountll(val); }
+static inline int LeastSignificantSetBit(u8 val) { return __builtin_ctz(val); }
+static inline int LeastSignificantSetBit(u16 val) { return __builtin_ctz(val); }
+static inline int LeastSignificantSetBit(u32 val) { return __builtin_ctz(val); }
+static inline int LeastSignificantSetBit(u64 val) { return __builtin_ctzll(val); }
+#endif
+
+// Similar to std::bitset, this is a class which encapsulates a bitset, i.e.
+// using the set bits of an integer to represent a set of integers.  Like that
+// class, it acts like an array of bools:
+//     BitSet32 bs;
+//     bs[1] = true;
+// but also like the underlying integer ([0] = least significant bit):
+//     BitSet32 bs2 = ...;
+//     bs = (bs ^ bs2) & BitSet32(0xffff);
+// The following additional functionality is provided:
+// - Construction using an initializer list.
+//     BitSet bs { 1, 2, 4, 8 };
+// - Efficiently iterating through the set bits:
+//     for (int i : bs)
+//         [i is the *index* of a set bit]
+//   (This uses the appropriate CPU instruction to find the next set bit in one
+//   operation.)
+// - Counting set bits using .Count() - see comment on that method.
+
+// TODO: use constexpr when MSVC gets out of the Dark Ages
+
+template <typename IntTy>
+class BitSet
+{
+    static_assert(!std::is_signed<IntTy>::value, "BitSet should not be used with signed types");
+public:
+    // A reference to a particular bit, returned from operator[].
+    class Ref
+    {
+    public:
+        Ref(Ref&& other) : m_bs(other.m_bs), m_mask(other.m_mask) {}
+        Ref(BitSet* bs, IntTy mask) : m_bs(bs), m_mask(mask) {}
+        operator bool() const { return (m_bs->m_val & m_mask) != 0; }
+        bool operator=(bool set)
+        {
+            m_bs->m_val = (m_bs->m_val & ~m_mask) | (set ? m_mask : 0);
+            return set;
+        }
+    private:
+        BitSet* m_bs;
+        IntTy m_mask;
+    };
+
+    // A STL-like iterator is required to be able to use range-based for loops.
+    class Iterator
+    {
+    public:
+        Iterator(const Iterator& other) : m_val(other.m_val), m_bit(other.m_bit) {}
+        Iterator(IntTy val, int bit) : m_val(val), m_bit(bit) {}
+        Iterator& operator=(Iterator other) { new (this) Iterator(other); return *this; }
+        int operator*() { return m_bit; }
+        Iterator& operator++()
+        {
+            if (m_val == 0)
+            {
+                m_bit = -1;
+            }
+            else
+            {
+                int bit = LeastSignificantSetBit(m_val);
+                m_val &= ~(1 << bit);
+                m_bit = bit;
+            }
+            return *this;
+        }
+        Iterator operator++(int _)
+        {
+            Iterator other(*this);
+            ++*this;
+            return other;
+        }
+        bool operator==(Iterator other) const { return m_bit == other.m_bit; }
+        bool operator!=(Iterator other) const { return m_bit != other.m_bit; }
+    private:
+        IntTy m_val;
+        int m_bit;
+    };
+
+    BitSet() : m_val(0) {}
+    explicit BitSet(IntTy val) : m_val(val) {}
+    BitSet(std::initializer_list<int> init)
+    {
+        m_val = 0;
+        for (int bit : init)
+            m_val |= (IntTy)1 << bit;
+    }
+
+    static BitSet AllTrue(size_t count)
+    {
+        return BitSet(count == sizeof(IntTy)*8 ? ~(IntTy)0 : (((IntTy)1 << count) - 1));
+    }
+
+    Ref operator[](size_t bit) { return Ref(this, (IntTy)1 << bit); }
+    const Ref operator[](size_t bit) const { return (*const_cast<BitSet*>(this))[bit]; }
+    bool operator==(BitSet other) const { return m_val == other.m_val; }
+    bool operator!=(BitSet other) const { return m_val != other.m_val; }
+    bool operator<(BitSet other) const { return m_val < other.m_val; }
+    bool operator>(BitSet other) const { return m_val > other.m_val; }
+    BitSet operator|(BitSet other) const { return BitSet(m_val | other.m_val); }
+    BitSet operator&(BitSet other) const { return BitSet(m_val & other.m_val); }
+    BitSet operator^(BitSet other) const { return BitSet(m_val ^ other.m_val); }
+    BitSet operator~() const { return BitSet(~m_val); }
+    BitSet& operator|=(BitSet other) { return *this = *this | other; }
+    BitSet& operator&=(BitSet other) { return *this = *this & other; }
+    BitSet& operator^=(BitSet other) { return *this = *this ^ other; }
+    operator u32() = delete;
+    operator bool() { return m_val != 0; }
+
+    // Warning: Even though on modern CPUs this is a single fast instruction,
+    // Dolphin's official builds do not currently assume POPCNT support on x86,
+    // so slower explicit bit twiddling is generated.  Still should generally
+    // be faster than a loop.
+    unsigned int Count() const { return CountSetBits(m_val); }
+
+    Iterator begin() const { Iterator it(m_val, 0); return ++it; }
+    Iterator end() const { return Iterator(m_val, -1); }
+
+    IntTy m_val;
+};
+
+} // Common
+
+typedef Common::BitSet<u8> BitSet8;
+typedef Common::BitSet<u16> BitSet16;
+typedef Common::BitSet<u32> BitSet32;
+typedef Common::BitSet<u64> BitSet64;
\ No newline at end of file
diff --git a/src/common/x64/abi.cpp b/src/common/x64/abi.cpp
index 4c07a6ebe..955eb86ce 100644
--- a/src/common/x64/abi.cpp
+++ b/src/common/x64/abi.cpp
@@ -22,247 +22,69 @@ using namespace Gen;
 
 // Shared code between Win64 and Unix64
 
-// Sets up a __cdecl function.
-void XEmitter::ABI_EmitPrologue(int maxCallParams)
-{
-#ifdef _M_IX86
-    // Don't really need to do anything
-#elif defined(ARCHITECTURE_x86_64)
-#if _WIN32
-    int stacksize = ((maxCallParams + 1) & ~1) * 8 + 8;
-    // Set up a stack frame so that we can call functions
-    // TODO: use maxCallParams
-    SUB(64, R(RSP), Imm8(stacksize));
-#endif
-#else
-#error Arch not supported
+void XEmitter::ABI_CalculateFrameSize(BitSet32 mask, size_t rsp_alignment, size_t needed_frame_size, size_t* shadowp, size_t* subtractionp, size_t* xmm_offsetp) {
+    size_t shadow = 0;
+#if defined(_WIN32)
+    shadow = 0x20;
 #endif
-}
-
-void XEmitter::ABI_EmitEpilogue(int maxCallParams)
-{
-#ifdef _M_IX86
-    RET();
-#elif defined(ARCHITECTURE_x86_64)
-#ifdef _WIN32
-    int stacksize = ((maxCallParams+1)&~1)*8 + 8;
-    ADD(64, R(RSP), Imm8(stacksize));
-#endif
-    RET();
-#else
-#error Arch not supported
-
-
-#endif
-}
-
-#ifdef _M_IX86 // All32
-
-// Shared code between Win32 and Unix32
-void XEmitter::ABI_CallFunction(const void *func) {
-    ABI_AlignStack(0);
-    CALL(func);
-    ABI_RestoreStack(0);
-}
-
-void XEmitter::ABI_CallFunctionC16(const void *func, u16 param1) {
-    ABI_AlignStack(1 * 2);
-    PUSH(16, Imm16(param1));
-    CALL(func);
-    ABI_RestoreStack(1 * 2);
-}
-
-void XEmitter::ABI_CallFunctionCC16(const void *func, u32 param1, u16 param2) {
-    ABI_AlignStack(1 * 2 + 1 * 4);
-    PUSH(16, Imm16(param2));
-    PUSH(32, Imm32(param1));
-    CALL(func);
-    ABI_RestoreStack(1 * 2 + 1 * 4);
-}
-
-void XEmitter::ABI_CallFunctionC(const void *func, u32 param1) {
-    ABI_AlignStack(1 * 4);
-    PUSH(32, Imm32(param1));
-    CALL(func);
-    ABI_RestoreStack(1 * 4);
-}
-
-void XEmitter::ABI_CallFunctionCC(const void *func, u32 param1, u32 param2) {
-    ABI_AlignStack(2 * 4);
-    PUSH(32, Imm32(param2));
-    PUSH(32, Imm32(param1));
-    CALL(func);
-    ABI_RestoreStack(2 * 4);
-}
-
-void XEmitter::ABI_CallFunctionCCC(const void *func, u32 param1, u32 param2, u32 param3) {
-    ABI_AlignStack(3 * 4);
-    PUSH(32, Imm32(param3));
-    PUSH(32, Imm32(param2));
-    PUSH(32, Imm32(param1));
-    CALL(func);
-    ABI_RestoreStack(3 * 4);
-}
-
-void XEmitter::ABI_CallFunctionCCP(const void *func, u32 param1, u32 param2, void *param3) {
-    ABI_AlignStack(3 * 4);
-    PUSH(32, ImmPtr(param3));
-    PUSH(32, Imm32(param2));
-    PUSH(32, Imm32(param1));
-    CALL(func);
-    ABI_RestoreStack(3 * 4);
-}
-
-void XEmitter::ABI_CallFunctionCCCP(const void *func, u32 param1, u32 param2,u32 param3, void *param4) {
-    ABI_AlignStack(4 * 4);
-    PUSH(32, ImmPtr(param4));
-    PUSH(32, Imm32(param3));
-    PUSH(32, Imm32(param2));
-    PUSH(32, Imm32(param1));
-    CALL(func);
-    ABI_RestoreStack(4 * 4);
-}
-
-void XEmitter::ABI_CallFunctionP(const void *func, void *param1) {
-    ABI_AlignStack(1 * 4);
-    PUSH(32, ImmPtr(param1));
-    CALL(func);
-    ABI_RestoreStack(1 * 4);
-}
-
-void XEmitter::ABI_CallFunctionPA(const void *func, void *param1, const Gen::OpArg &arg2) {
-    ABI_AlignStack(2 * 4);
-    PUSH(32, arg2);
-    PUSH(32, ImmPtr(param1));
-    CALL(func);
-    ABI_RestoreStack(2 * 4);
-}
-
-void XEmitter::ABI_CallFunctionPAA(const void *func, void *param1, const Gen::OpArg &arg2, const Gen::OpArg &arg3) {
-    ABI_AlignStack(3 * 4);
-    PUSH(32, arg3);
-    PUSH(32, arg2);
-    PUSH(32, ImmPtr(param1));
-    CALL(func);
-    ABI_RestoreStack(3 * 4);
-}
-
-void XEmitter::ABI_CallFunctionPPC(const void *func, void *param1, void *param2, u32 param3) {
-    ABI_AlignStack(3 * 4);
-    PUSH(32, Imm32(param3));
-    PUSH(32, ImmPtr(param2));
-    PUSH(32, ImmPtr(param1));
-    CALL(func);
-    ABI_RestoreStack(3 * 4);
-}
-
-// Pass a register as a parameter.
-void XEmitter::ABI_CallFunctionR(const void *func, X64Reg reg1) {
-    ABI_AlignStack(1 * 4);
-    PUSH(32, R(reg1));
-    CALL(func);
-    ABI_RestoreStack(1 * 4);
-}
-
-// Pass two registers as parameters.
-void XEmitter::ABI_CallFunctionRR(const void *func, Gen::X64Reg reg1, Gen::X64Reg reg2)
-{
-    ABI_AlignStack(2 * 4);
-    PUSH(32, R(reg2));
-    PUSH(32, R(reg1));
-    CALL(func);
-    ABI_RestoreStack(2 * 4);
-}
 
-void XEmitter::ABI_CallFunctionAC(const void *func, const Gen::OpArg &arg1, u32 param2)
-{
-    ABI_AlignStack(2 * 4);
-    PUSH(32, Imm32(param2));
-    PUSH(32, arg1);
-    CALL(func);
-    ABI_RestoreStack(2 * 4);
-}
+    int count = (mask & ABI_ALL_GPRS).Count();
+    rsp_alignment -= count * 8;
+    size_t subtraction = 0;
+    int fpr_count = (mask & ABI_ALL_FPRS).Count();
+    if (fpr_count) {
+        // If we have any XMMs to save, we must align the stack here.
+        subtraction = rsp_alignment & 0xf;
+    }
+    subtraction += 16 * fpr_count;
+    size_t xmm_base_subtraction = subtraction;
+    subtraction += needed_frame_size;
+    subtraction += shadow;
+    // Final alignment.
+    rsp_alignment -= subtraction;
+    subtraction += rsp_alignment & 0xf;
 
-void XEmitter::ABI_CallFunctionACC(const void *func, const Gen::OpArg &arg1, u32 param2, u32 param3)
-{
-    ABI_AlignStack(3 * 4);
-    PUSH(32, Imm32(param3));
-    PUSH(32, Imm32(param2));
-    PUSH(32, arg1);
-    CALL(func);
-    ABI_RestoreStack(3 * 4);
+    *shadowp = shadow;
+    *subtractionp = subtraction;
+    *xmm_offsetp = subtraction - xmm_base_subtraction;
 }
 
-void XEmitter::ABI_CallFunctionA(const void *func, const Gen::OpArg &arg1)
-{
-    ABI_AlignStack(1 * 4);
-    PUSH(32, arg1);
-    CALL(func);
-    ABI_RestoreStack(1 * 4);
-}
+size_t XEmitter::ABI_PushRegistersAndAdjustStack(BitSet32 mask, size_t rsp_alignment, size_t needed_frame_size) {
+    size_t shadow, subtraction, xmm_offset;
+    ABI_CalculateFrameSize(mask, rsp_alignment, needed_frame_size, &shadow, &subtraction, &xmm_offset);
 
-void XEmitter::ABI_CallFunctionAA(const void *func, const Gen::OpArg &arg1, const Gen::OpArg &arg2)
-{
-    ABI_AlignStack(2 * 4);
-    PUSH(32, arg2);
-    PUSH(32, arg1);
-    CALL(func);
-    ABI_RestoreStack(2 * 4);
-}
+    for (int r : mask & ABI_ALL_GPRS)
+        PUSH((X64Reg)r);
 
-void XEmitter::ABI_PushAllCalleeSavedRegsAndAdjustStack() {
-    // Note: 4 * 4 = 16 bytes, so alignment is preserved.
-    PUSH(EBP);
-    PUSH(EBX);
-    PUSH(ESI);
-    PUSH(EDI);
-}
+    if (subtraction)
+        SUB(64, R(RSP), subtraction >= 0x80 ? Imm32((u32)subtraction) : Imm8((u8)subtraction));
 
-void XEmitter::ABI_PopAllCalleeSavedRegsAndAdjustStack() {
-    POP(EDI);
-    POP(ESI);
-    POP(EBX);
-    POP(EBP);
-}
+    for (int x : mask & ABI_ALL_FPRS) {
+        MOVAPD(MDisp(RSP, (int)xmm_offset), (X64Reg)(x - 16));
+        xmm_offset += 16;
+    }
 
-unsigned int XEmitter::ABI_GetAlignedFrameSize(unsigned int frameSize) {
-    frameSize += 4; // reserve space for return address
-    unsigned int alignedSize =
-#ifdef __GNUC__
-        (frameSize + 15) & -16;
-#else
-        (frameSize + 3) & -4;
-#endif
-    return alignedSize;
+    return shadow;
 }
 
+void XEmitter::ABI_PopRegistersAndAdjustStack(BitSet32 mask, size_t rsp_alignment, size_t needed_frame_size) {
+    size_t shadow, subtraction, xmm_offset;
+    ABI_CalculateFrameSize(mask, rsp_alignment, needed_frame_size, &shadow, &subtraction, &xmm_offset);
 
-void XEmitter::ABI_AlignStack(unsigned int frameSize) {
-// Mac OS X requires the stack to be 16-byte aligned before every call.
-// Linux requires the stack to be 16-byte aligned before calls that put SSE
-// vectors on the stack, but since we do not keep track of which calls do that,
-// it is effectively every call as well.
-// Windows binaries compiled with MSVC do not have such a restriction*, but I
-// expect that GCC on Windows acts the same as GCC on Linux in this respect.
-// It would be nice if someone could verify this.
-// *However, the MSVC optimizing compiler assumes a 4-byte-aligned stack at times.
-    unsigned int fillSize =
-        ABI_GetAlignedFrameSize(frameSize) - (frameSize + 4);
-    if (fillSize != 0) {
-        SUB(32, R(ESP), Imm8(fillSize));
+    for (int x : mask & ABI_ALL_FPRS) {
+        MOVAPD((X64Reg) (x - 16), MDisp(RSP, (int)xmm_offset));
+        xmm_offset += 16;
     }
-}
 
-void XEmitter::ABI_RestoreStack(unsigned int frameSize) {
-    unsigned int alignedSize = ABI_GetAlignedFrameSize(frameSize);
-    alignedSize -= 4; // return address is POPped at end of call
-    if (alignedSize != 0) {
-        ADD(32, R(ESP), Imm8(alignedSize));
+    if (subtraction)
+        ADD(64, R(RSP), subtraction >= 0x80 ? Imm32((u32)subtraction) : Imm8((u8)subtraction));
+
+    for (int r = 15; r >= 0; r--) {
+        if (mask[r])
+            POP((X64Reg)r);
     }
 }
 
-#else //64bit
-
 // Common functions
 void XEmitter::ABI_CallFunction(const void *func) {
     u64 distance = u64(func) - (u64(code) + 5);
@@ -538,143 +360,4 @@ void XEmitter::ABI_CallFunctionAA(const void *func, const Gen::OpArg &arg1, cons
     } else {
         CALL(func);
     }
-}
-
-unsigned int XEmitter::ABI_GetAlignedFrameSize(unsigned int frameSize) {
-    return frameSize;
-}
-
-#ifdef _WIN32
-
-// The Windows x64 ABI requires XMM6 - XMM15 to be callee saved.  10 regs.
-// But, not saving XMM4 and XMM5 breaks things in VS 2010, even though they are volatile regs.
-// Let's just save all 16.
-const int XMM_STACK_SPACE = 16 * 16;
-
-// Win64 Specific Code
-void XEmitter::ABI_PushAllCalleeSavedRegsAndAdjustStack() {
-    //we only want to do this once
-    PUSH(RBX);
-    PUSH(RSI);
-    PUSH(RDI);
-    PUSH(RBP);
-    PUSH(R12);
-    PUSH(R13);
-    PUSH(R14);
-    PUSH(R15);
-    ABI_AlignStack(0);
-
-    // Do this after aligning, because before it's offset by 8.
-    SUB(64, R(RSP), Imm32(XMM_STACK_SPACE));
-    for (int i = 0; i < 16; ++i)
-        MOVAPS(MDisp(RSP, i * 16), (X64Reg)(XMM0 + i));
-}
-
-void XEmitter::ABI_PopAllCalleeSavedRegsAndAdjustStack() {
-    for (int i = 0; i < 16; ++i)
-        MOVAPS((X64Reg)(XMM0 + i), MDisp(RSP, i * 16));
-    ADD(64, R(RSP), Imm32(XMM_STACK_SPACE));
-
-    ABI_RestoreStack(0);
-    POP(R15);
-    POP(R14);
-    POP(R13);
-    POP(R12);
-    POP(RBP);
-    POP(RDI);
-    POP(RSI);
-    POP(RBX);
-}
-
-// Win64 Specific Code
-void XEmitter::ABI_PushAllCallerSavedRegsAndAdjustStack() {
-    PUSH(RCX);
-    PUSH(RDX);
-    PUSH(RSI);
-    PUSH(RDI);
-    PUSH(R8);
-    PUSH(R9);
-    PUSH(R10);
-    PUSH(R11);
-    // TODO: Callers preserve XMM4-5 (XMM0-3 are args.)
-    ABI_AlignStack(0);
-}
-
-void XEmitter::ABI_PopAllCallerSavedRegsAndAdjustStack() {
-    ABI_RestoreStack(0);
-    POP(R11);
-    POP(R10);
-    POP(R9);
-    POP(R8);
-    POP(RDI);
-    POP(RSI);
-    POP(RDX);
-    POP(RCX);
-}
-
-void XEmitter::ABI_AlignStack(unsigned int /*frameSize*/) {
-    SUB(64, R(RSP), Imm8(0x28));
-}
-
-void XEmitter::ABI_RestoreStack(unsigned int /*frameSize*/) {
-    ADD(64, R(RSP), Imm8(0x28));
-}
-
-#else
-// Unix64 Specific Code
-void XEmitter::ABI_PushAllCalleeSavedRegsAndAdjustStack() {
-    PUSH(RBX);
-    PUSH(RBP);
-    PUSH(R12);
-    PUSH(R13);
-    PUSH(R14);
-    PUSH(R15);
-    PUSH(R15); //just to align stack. duped push/pop doesn't hurt.
-    // TODO: XMM?
-}
-
-void XEmitter::ABI_PopAllCalleeSavedRegsAndAdjustStack() {
-    POP(R15);
-    POP(R15);
-    POP(R14);
-    POP(R13);
-    POP(R12);
-    POP(RBP);
-    POP(RBX);
-}
-
-void XEmitter::ABI_PushAllCallerSavedRegsAndAdjustStack() {
-    PUSH(RCX);
-    PUSH(RDX);
-    PUSH(RSI);
-    PUSH(RDI);
-    PUSH(R8);
-    PUSH(R9);
-    PUSH(R10);
-    PUSH(R11);
-    PUSH(R11);
-}
-
-void XEmitter::ABI_PopAllCallerSavedRegsAndAdjustStack() {
-    POP(R11);
-    POP(R11);
-    POP(R10);
-    POP(R9);
-    POP(R8);
-    POP(RDI);
-    POP(RSI);
-    POP(RDX);
-    POP(RCX);
-}
-
-void XEmitter::ABI_AlignStack(unsigned int /*frameSize*/) {
-    SUB(64, R(RSP), Imm8(0x08));
-}
-
-void XEmitter::ABI_RestoreStack(unsigned int /*frameSize*/) {
-    ADD(64, R(RSP), Imm8(0x08));
-}
-
-#endif // WIN32
-
-#endif // 32bit
+}
\ No newline at end of file
diff --git a/src/common/x64/abi.h b/src/common/x64/abi.h
index 7e9c156ae..de6d62fdd 100644
--- a/src/common/x64/abi.h
+++ b/src/common/x64/abi.h
@@ -1,35 +1,15 @@
-// Copyright (C) 2003 Dolphin Project.
-
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU General Public License as published by
-// the Free Software Foundation, version 2.0 or later versions.
-
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU General Public License 2.0 for more details.
-
-// A copy of the GPL 2.0 should have been included with the program.
-// If not, see http://www.gnu.org/licenses/
-
-// Official SVN repository and contact information can be found at
-// http://code.google.com/p/dolphin-emu/
+// Copyright 2008 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
 
 #pragma once
 
-#include "common/common_types.h"
+#include "common/bit_set.h"
+#include "emitter.h"
 
-// x86/x64 ABI:s, and helpers to help follow them when JIT-ing code.
+// x64 ABI:s, and helpers to help follow them when JIT-ing code.
 // All convensions return values in EAX (+ possibly EDX).
 
-// Linux 32-bit, Windows 32-bit (cdecl, System V):
-// * Caller pushes left to right
-// * Caller fixes stack after call
-// * function subtract from stack for local storage only.
-// Scratch:      EAX ECX EDX
-// Callee-save:  EBX ESI EDI EBP
-// Parameters:   -
-
 // Windows 64-bit
 // * 4-reg "fastcall" variant, very new-skool stack handling
 // * Callee moves stack pointer, to make room for shadow regs for the biggest function _it itself calls_
@@ -44,18 +24,8 @@
 // Callee-save:  RBX RBP R12 R13 R14 R15
 // Parameters:   RDI RSI RDX RCX R8 R9
 
-#ifdef _M_IX86 // 32 bit calling convention, shared by all
-
-// 32-bit don't pass parameters in regs, but these are convenient to have anyway when we have to
-// choose regs to put stuff in.
-#define ABI_PARAM1 RCX
-#define ABI_PARAM2 RDX
-
-// There are no ABI_PARAM* here, since args are pushed.
-// 32-bit bog standard cdecl, shared between linux and windows
-// MacOSX 32-bit is same as System V with a few exceptions that we probably don't care much about.
-
-#elif ARCHITECTURE_x86_64 // 64 bit calling convention
+#define ABI_ALL_FPRS BitSet32(0xffff0000)
+#define ABI_ALL_GPRS BitSet32(0x0000ffff)
 
 #ifdef _WIN32 // 64-bit Windows - the really exotic calling convention
 
@@ -64,7 +34,11 @@
 #define ABI_PARAM3 R8
 #define ABI_PARAM4 R9
 
-#else  //64-bit Unix (hopefully MacOSX too)
+// xmm0-xmm15 use the upper 16 bits in the functions that push/pop registers.
+#define ABI_ALL_CALLER_SAVED \
+    (BitSet32 { RAX, RCX, RDX, R8, R9, R10, R11, \
+                XMM0+16, XMM1+16, XMM2+16, XMM3+16, XMM4+16, XMM5+16 })
+#else //64-bit Unix / OS X
 
 #define ABI_PARAM1 RDI
 #define ABI_PARAM2 RSI
@@ -73,6 +47,13 @@
 #define ABI_PARAM5 R8
 #define ABI_PARAM6 R9
 
+// TODO: Avoid pushing all 16 XMM registers when possible. Most functions we call probably
+// don't actually clobber them.
+#define ABI_ALL_CALLER_SAVED \
+    (BitSet32 { RAX, RCX, RDX, RDI, RSI, R8, R9, R10, R11 } | \
+     ABI_ALL_FPRS)
 #endif // WIN32
 
-#endif // X86
+#define ABI_ALL_CALLEE_SAVED (~ABI_ALL_CALLER_SAVED)
+
+#define ABI_RETURN RAX
diff --git a/src/common/x64/emitter.h b/src/common/x64/emitter.h
index a49cd2cf1..2dd0dc94e 100644
--- a/src/common/x64/emitter.h
+++ b/src/common/x64/emitter.h
@@ -18,6 +18,7 @@
 #pragma once
 
 #include "common/assert.h"
+#include "common/bit_set.h"
 #include "common/common_types.h"
 #include "common/code_block.h"
 
@@ -356,7 +357,7 @@ private:
     void WriteFloatLoadStore(int bits, FloatOp op, FloatOp op_80b, const OpArg& arg);
     void WriteNormalOp(XEmitter *emit, int bits, NormalOp op, const OpArg& a1, const OpArg& a2);
 
-    void ABI_CalculateFrameSize(u32 mask, size_t rsp_alignment, size_t needed_frame_size, size_t* shadowp, size_t* subtractionp, size_t* xmm_offsetp);
+    void ABI_CalculateFrameSize(BitSet32 mask, size_t rsp_alignment, size_t needed_frame_size, size_t* shadowp, size_t* subtractionp, size_t* xmm_offsetp);
 
 protected:
     void Write8(u8 value);
@@ -1007,25 +1008,26 @@ public:
         ABI_CallFunctionC((const void*)func, param1);
     }
 
-    // A function that doesn't have any control over what it will do to regs,
-    // such as the dispatcher, should be surrounded by these.
-    void ABI_PushAllCalleeSavedRegsAndAdjustStack();
-    void ABI_PopAllCalleeSavedRegsAndAdjustStack();
-
-    // A function that doesn't know anything about it's surroundings, should
-    // be surrounded by these to establish a safe environment, where it can roam free.
-    // An example is a backpatch injected function.
-    void ABI_PushAllCallerSavedRegsAndAdjustStack();
-    void ABI_PopAllCallerSavedRegsAndAdjustStack();
-
-    unsigned int ABI_GetAlignedFrameSize(unsigned int frameSize);
-    void ABI_AlignStack(unsigned int frameSize);
-    void ABI_RestoreStack(unsigned int frameSize);
-
-    // Sets up a __cdecl function.
-    // Only x64 really needs the parameter count.
-    void ABI_EmitPrologue(int maxCallParams);
-    void ABI_EmitEpilogue(int maxCallParams);
+    /**
+     * Saves specified registers and adjusts the stack to be 16-byte aligned as required by the ABI
+     *
+     * @param mask Registers to push on the stack (high 16 bits are XMMs, low 16 bits are GPRs)
+     * @param rsp_alignment Current alignment of the stack pointer, must be 0 or 8
+     * @param needed_frame_size Additional space needed, e.g., for function arguments passed on the stack
+     * @return Size of the shadow space, i.e., offset of the frame
+     */
+    size_t ABI_PushRegistersAndAdjustStack(BitSet32 mask, size_t rsp_alignment, size_t needed_frame_size = 0);
+
+    /**
+     * Restores specified registers and adjusts the stack to its original alignment, i.e., the alignment before
+     * the matching PushRegistersAndAdjustStack.
+     *
+     * @param mask Registers to restores from the stack (high 16 bits are XMMs, low 16 bits are GPRs)
+     * @param rsp_alignment Original alignment before the matching PushRegistersAndAdjustStack, must be 0 or 8
+     * @param needed_frame_size Additional space that was needed
+     * @warning Stack must be currently 16-byte aligned
+     */
+    void ABI_PopRegistersAndAdjustStack(BitSet32 mask, size_t rsp_alignment, size_t needed_frame_size = 0);
 
     #ifdef _M_IX86
     static int ABI_GetNumXMMRegs() { return 8; }
diff --git a/src/video_core/shader/shader_jit_x64.cpp b/src/video_core/shader/shader_jit_x64.cpp
index 1039c8df4..b9a0b19e3 100644
--- a/src/video_core/shader/shader_jit_x64.cpp
+++ b/src/video_core/shader/shader_jit_x64.cpp
@@ -122,6 +122,14 @@ static const X64Reg ONE = XMM14;
 /// Constant vector of [-0.f, -0.f, -0.f, -0.f], used to efficiently negate a vector with XOR
 static const X64Reg NEGBIT = XMM15;
 
+// State registers that must not be modified by external functions calls
+// Scratch registers, e.g., SRC1 and SCRATCH, have to be saved on the side if needed
+static const BitSet32 persistent_regs = {
+    UNIFORMS, REGISTERS, // Pointers to register blocks
+    ADDROFFS_REG_0, ADDROFFS_REG_1, LOOPCOUNT_REG, COND0, COND1, // Cached registers
+    ONE+16, NEGBIT+16, // Constants
+};
+
 /// Raw constant for the source register selector that indicates no swizzling is performed
 static const u8 NO_SRC_REG_SWIZZLE = 0x1b;
 /// Raw constant for the destination register enable mask that indicates all components are enabled
@@ -295,20 +303,8 @@ void JitCompiler::Compile_UniformCondition(Instruction instr) {
     CMP(sizeof(bool) * 8, MDisp(UNIFORMS, offset), Imm8(0));
 }
 
-void JitCompiler::Compile_PushCallerSavedXMM() {
-#ifndef _WIN32
-    SUB(64, R(RSP), Imm8(2 * 16));
-    MOVUPS(MDisp(RSP, 16), ONE);
-    MOVUPS(MDisp(RSP, 0), NEGBIT);
-#endif
-}
-
-void JitCompiler::Compile_PopCallerSavedXMM() {
-#ifndef _WIN32
-    MOVUPS(NEGBIT, MDisp(RSP, 0));
-    MOVUPS(ONE, MDisp(RSP, 16));
-    ADD(64, R(RSP), Imm8(2 * 16));
-#endif
+BitSet32 JitCompiler::PersistentCallerSavedRegs() {
+    return persistent_regs & ABI_ALL_CALLER_SAVED;
 }
 
 void JitCompiler::Compile_ADD(Instruction instr) {
@@ -390,12 +386,9 @@ void JitCompiler::Compile_EX2(Instruction instr) {
     Compile_SwizzleSrc(instr, 1, instr.common.src1, SRC1);
     MOVSS(XMM0, R(SRC1));
 
-    // The following will actually break the stack alignment
-    ABI_PushAllCallerSavedRegsAndAdjustStack();
-    Compile_PushCallerSavedXMM();
+    ABI_PushRegistersAndAdjustStack(PersistentCallerSavedRegs(), 0);
     ABI_CallFunction(reinterpret_cast<const void*>(exp2f));
-    Compile_PopCallerSavedXMM();
-    ABI_PopAllCallerSavedRegsAndAdjustStack();
+    ABI_PopRegistersAndAdjustStack(PersistentCallerSavedRegs(), 0);
 
     SHUFPS(XMM0, R(XMM0), _MM_SHUFFLE(0, 0, 0, 0));
     MOVAPS(SRC1, R(XMM0));
@@ -406,12 +399,9 @@ void JitCompiler::Compile_LG2(Instruction instr) {
     Compile_SwizzleSrc(instr, 1, instr.common.src1, SRC1);
     MOVSS(XMM0, R(SRC1));
 
-    // The following will actually break the stack alignment
-    ABI_PushAllCallerSavedRegsAndAdjustStack();
-    Compile_PushCallerSavedXMM();
+    ABI_PushRegistersAndAdjustStack(PersistentCallerSavedRegs(), 0);
     ABI_CallFunction(reinterpret_cast<const void*>(log2f));
-    Compile_PopCallerSavedXMM();
-    ABI_PopAllCallerSavedRegsAndAdjustStack();
+    ABI_PopRegistersAndAdjustStack(PersistentCallerSavedRegs(), 0);
 
     SHUFPS(XMM0, R(XMM0), _MM_SHUFFLE(0, 0, 0, 0));
     MOVAPS(SRC1, R(XMM0));
@@ -560,7 +550,7 @@ void JitCompiler::Compile_NOP(Instruction instr) {
 }
 
 void JitCompiler::Compile_END(Instruction instr) {
-    ABI_PopAllCalleeSavedRegsAndAdjustStack();
+    ABI_PopRegistersAndAdjustStack(ABI_ALL_CALLEE_SAVED, 8);
     RET();
 }
 
@@ -756,7 +746,8 @@ CompiledShader* JitCompiler::Compile() {
     const auto& code = g_state.vs.program_code;
     unsigned offset = g_state.regs.vs.main_offset;
 
-    ABI_PushAllCalleeSavedRegsAndAdjustStack();
+    // The stack pointer is 8 modulo 16 at the entry of a procedure
+    ABI_PushRegistersAndAdjustStack(ABI_ALL_CALLEE_SAVED, 8);
 
     MOV(PTRBITS, R(REGISTERS), R(ABI_PARAM1));
     MOV(PTRBITS, R(UNIFORMS), ImmPtr(&g_state.vs.uniforms));
diff --git a/src/video_core/shader/shader_jit_x64.h b/src/video_core/shader/shader_jit_x64.h
index 58828ecc8..8668cfff4 100644
--- a/src/video_core/shader/shader_jit_x64.h
+++ b/src/video_core/shader/shader_jit_x64.h
@@ -77,8 +77,7 @@ private:
     void Compile_EvaluateCondition(Instruction instr);
     void Compile_UniformCondition(Instruction instr);
 
-    void Compile_PushCallerSavedXMM();
-    void Compile_PopCallerSavedXMM();
+    BitSet32 PersistentCallerSavedRegs();
 
     /// Pointer to the variable that stores the current Pica code offset. Used to handle nested code blocks.
     unsigned* offset_ptr = nullptr;