[dynarmic] exclude r13 and r14 from regsel

src/dynarmic/src/dynarmic/backend/x64/a32_emit_x64.cpp

@@ -109,12 +109,12 @@ A32EmitX64::BlockDescriptor A32EmitX64::Emit(IR::Block& block) {
 
     const boost::container::static_vector<HostLoc, 28> gpr_order = [this] {
         boost::container::static_vector<HostLoc, 28> gprs{any_gpr};
-        if (conf.page_table) {
-            gprs.erase(std::find(gprs.begin(), gprs.end(), HostLoc::R14));
-        }
         if (conf.fastmem_pointer) {
             gprs.erase(std::find(gprs.begin(), gprs.end(), HostLoc::R13));
         }
+        if (conf.page_table) {
+            gprs.erase(std::find(gprs.begin(), gprs.end(), HostLoc::R14));
+        }
         return gprs;
     }();
 

src/dynarmic/src/dynarmic/backend/x64/a64_emit_x64.cpp

@@ -80,12 +80,12 @@ A64EmitX64::BlockDescriptor A64EmitX64::Emit(IR::Block& block) noexcept {
 
     const boost::container::static_vector<HostLoc, 28> gpr_order = [this] {
         boost::container::static_vector<HostLoc, 28> gprs{any_gpr};
-        if (conf.page_table) {
-            gprs.erase(std::find(gprs.begin(), gprs.end(), HostLoc::R14));
-        }
         if (conf.fastmem_pointer) {
             gprs.erase(std::find(gprs.begin(), gprs.end(), HostLoc::R13));
         }
+        if (conf.page_table) {
+            gprs.erase(std::find(gprs.begin(), gprs.end(), HostLoc::R14));
+        }
         return gprs;
     }();
 

src/dynarmic/src/dynarmic/backend/x64/block_of_code.cpp

@@ -331,6 +331,8 @@ void BlockOfCode::GenRunCode(std::function<void(BlockOfCode&)> rcp) {
         mov(qword[rsp + ABI_SHADOW_SPACE + offsetof(StackLayout, cycles_remaining)], ABI_RETURN);
     }
 
+    // r14 = page table
+    // r13 = fastmem pointer
     rcp(*this);
 
     cmp(dword[r15 + jsi.offsetof_halt_reason], 0);

src/dynarmic/src/dynarmic/backend/x64/reg_alloc.cpp

@@ -432,6 +432,11 @@ HostLoc RegAlloc::SelectARegister(const boost::container::static_vector<HostLoc,
         // Abstain from using upper registers unless absolutely nescesary
         if (loc_info.IsLocked()) {
             // skip, not suitable for allocation
+        // While R13 and R14 are technically available, we avoid allocating for them
+        // at all costs, because theoretically skipping them is better than spilling
+        // all over the place - it also fixes bugs with high reg pressure
+        } else if (*it >= HostLoc::R13 && *it <= HostLoc::R15) {
+            // skip, do not touch
         } else {
             if (loc_info.lru_counter < min_lru_counter) {
                 if (loc_info.IsEmpty())

src/dynarmic/tests/A64/a64.cpp

@@ -8,7 +8,6 @@
 
 #include "./testenv.h"
 #include "dynarmic/common/fp/fpsr.h"
-#include "dynarmic/common/llvm_disassemble.h"
 #include "dynarmic/interface/exclusive_monitor.h"
 
 using namespace Dynarmic;