emit_arm64: Add BlockRelocationType::MoveToScratch0

src/dynarmic/backend/arm64/address_space.cpp

@@ -124,13 +124,27 @@ static void LinkBlockLinks(const CodePtr entry_point, const CodePtr target_ptr,
     using namespace oaknut;
     using namespace oaknut::util;
 
-    for (auto [ptr_offset] : block_relocations_list) {
+    for (auto [ptr_offset, type] : block_relocations_list) {
         CodeGenerator c{reinterpret_cast<u32*>(entry_point + ptr_offset)};
 
-        if (target_ptr) {
+        switch (type) {
-            c.B((void*)target_ptr);
+        case BlockRelocationType::Branch:
-        } else {
+            if (target_ptr) {
-            c.NOP();
+                c.B((void*)target_ptr);
+            } else {
+                c.NOP();
+            }
+            break;
+        case BlockRelocationType::MoveToScratch0:
+            if (target_ptr) {
+                c.ADRL(Xscratch0, (void*)target_ptr);
+            } else {
+                c.NOP();
+                c.NOP();
+            }
+            break;
+        default:
+            ASSERT_FALSE("Invalid BlockRelocationType");
         }
     }
 }

src/dynarmic/backend/arm64/emit_arm64.cpp

@@ -256,9 +256,19 @@ void EmitRelocation(oaknut::CodeGenerator& code, EmitContext& ctx, LinkTarget li
     code.NOP();
 }
 
-void EmitBlockLinkRelocation(oaknut::CodeGenerator& code, EmitContext& ctx, const IR::LocationDescriptor& descriptor) {
+void EmitBlockLinkRelocation(oaknut::CodeGenerator& code, EmitContext& ctx, const IR::LocationDescriptor& descriptor, BlockRelocationType type) {
-    ctx.ebi.block_relocations[descriptor].emplace_back(BlockRelocation{code.ptr<CodePtr>() - ctx.ebi.entry_point});
+    ctx.ebi.block_relocations[descriptor].emplace_back(BlockRelocation{code.ptr<CodePtr>() - ctx.ebi.entry_point, type});
-    code.NOP();
+    switch (type) {
+    case BlockRelocationType::Branch:
+        code.NOP();
+        break;
+    case BlockRelocationType::MoveToScratch0:
+        code.NOP();
+        code.NOP();
+        break;
+    default:
+        UNREACHABLE();
+    }
 }
 
 }  // namespace Dynarmic::Backend::Arm64

src/dynarmic/backend/arm64/emit_arm64.h

@@ -91,8 +91,14 @@ struct Relocation {
     LinkTarget target;
 };
 
+enum class BlockRelocationType {
+    Branch,
+    MoveToScratch0,
+};
+
 struct BlockRelocation {
     std::ptrdiff_t code_offset;
+    BlockRelocationType type;
 };
 
 struct EmittedBlockInfo {
@@ -165,7 +171,7 @@ EmittedBlockInfo EmitArm64(oaknut::CodeGenerator& code, IR::Block block, const E
 template<IR::Opcode op>
 void EmitIR(oaknut::CodeGenerator& code, EmitContext& ctx, IR::Inst* inst);
 void EmitRelocation(oaknut::CodeGenerator& code, EmitContext& ctx, LinkTarget link_target);
-void EmitBlockLinkRelocation(oaknut::CodeGenerator& code, EmitContext& ctx, const IR::LocationDescriptor& descriptor);
+void EmitBlockLinkRelocation(oaknut::CodeGenerator& code, EmitContext& ctx, const IR::LocationDescriptor& descriptor, BlockRelocationType type);
 oaknut::Label EmitA32Cond(oaknut::CodeGenerator& code, EmitContext& ctx, IR::Cond cond);
 oaknut::Label EmitA64Cond(oaknut::CodeGenerator& code, EmitContext& ctx, IR::Cond cond);
 void EmitA32Terminal(oaknut::CodeGenerator& code, EmitContext& ctx);

src/dynarmic/backend/arm64/emit_arm64_a32.cpp

@@ -67,11 +67,11 @@ void EmitA32Terminal(oaknut::CodeGenerator& code, EmitContext& ctx, IR::Term::Li
         if (ctx.conf.enable_cycle_counting) {
             code.CMP(Xticks, 0);
             code.B(LE, fail);
-            EmitBlockLinkRelocation(code, ctx, terminal.next);
+            EmitBlockLinkRelocation(code, ctx, terminal.next, BlockRelocationType::Branch);
         } else {
             code.LDAR(Wscratch0, Xhalt);
             code.CBNZ(Wscratch0, fail);
-            EmitBlockLinkRelocation(code, ctx, terminal.next);
+            EmitBlockLinkRelocation(code, ctx, terminal.next, BlockRelocationType::Branch);
         }
     }
 
@@ -85,7 +85,7 @@ void EmitA32Terminal(oaknut::CodeGenerator& code, EmitContext& ctx, IR::Term::Li
     EmitSetUpperLocationDescriptor(code, ctx, terminal.next, initial_location);
 
     if (ctx.conf.HasOptimization(OptimizationFlag::BlockLinking) && !is_single_step) {
-        EmitBlockLinkRelocation(code, ctx, terminal.next);
+        EmitBlockLinkRelocation(code, ctx, terminal.next, BlockRelocationType::Branch);
     }
 
     code.MOV(Wscratch0, A32::LocationDescriptor{terminal.next}.PC());

src/dynarmic/backend/arm64/emit_arm64_a64.cpp

@@ -46,11 +46,11 @@ void EmitA64Terminal(oaknut::CodeGenerator& code, EmitContext& ctx, IR::Term::Li
         if (ctx.conf.enable_cycle_counting) {
             code.CMP(Xticks, 0);
             code.B(LE, fail);
-            EmitBlockLinkRelocation(code, ctx, terminal.next);
+            EmitBlockLinkRelocation(code, ctx, terminal.next, BlockRelocationType::Branch);
         } else {
             code.LDAR(Wscratch0, Xhalt);
             code.CBNZ(Wscratch0, fail);
-            EmitBlockLinkRelocation(code, ctx, terminal.next);
+            EmitBlockLinkRelocation(code, ctx, terminal.next, BlockRelocationType::Branch);
         }
     }
 
@@ -62,7 +62,7 @@ void EmitA64Terminal(oaknut::CodeGenerator& code, EmitContext& ctx, IR::Term::Li
 
 void EmitA64Terminal(oaknut::CodeGenerator& code, EmitContext& ctx, IR::Term::LinkBlockFast terminal, IR::LocationDescriptor, bool is_single_step) {
     if (ctx.conf.HasOptimization(OptimizationFlag::BlockLinking) && !is_single_step) {
-        EmitBlockLinkRelocation(code, ctx, terminal.next);
+        EmitBlockLinkRelocation(code, ctx, terminal.next, BlockRelocationType::Branch);
     }
 
     code.MOV(Xscratch0, A64::LocationDescriptor{terminal.next}.PC());