From b6bb94872adbe69463a05f04e823865658a0db1c Mon Sep 17 00:00:00 2001
From: Merry <git@mary.rs>
Date: Sat, 23 Jul 2022 00:02:45 +0100
Subject: [PATCH] backend/arm64: Implement IsZero64

---
 .../backend/arm64/emit_arm64_data_processing.cpp    | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/dynarmic/backend/arm64/emit_arm64_data_processing.cpp b/src/dynarmic/backend/arm64/emit_arm64_data_processing.cpp
index a81b7336..8c40c046 100644
--- a/src/dynarmic/backend/arm64/emit_arm64_data_processing.cpp
+++ b/src/dynarmic/backend/arm64/emit_arm64_data_processing.cpp
@@ -142,10 +142,15 @@ void EmitIR<IR::Opcode::IsZero32>(oaknut::CodeGenerator& code, EmitContext& ctx,
 
 template<>
 void EmitIR<IR::Opcode::IsZero64>(oaknut::CodeGenerator& code, EmitContext& ctx, IR::Inst* inst) {
-    (void)code;
-    (void)ctx;
-    (void)inst;
-    ASSERT_FALSE("Unimplemented");
+    // TODO: Use host flags
+    auto args = ctx.reg_alloc.GetArgumentInfo(inst);
+
+    auto Wresult = ctx.reg_alloc.WriteW(inst);
+    auto Xoperand = ctx.reg_alloc.ReadX(args[0]);
+    RegAlloc::Realize(Wresult, Xoperand);
+
+    code.CMP(Xoperand, 0);
+    code.CSET(Wresult, EQ);
 }
 
 template<>