From 58f339903238cbe3becec9202369f08054688739 Mon Sep 17 00:00:00 2001
From: MerryMage <MerryMage@users.noreply.github.com>
Date: Mon, 16 Jul 2018 18:24:29 +0100
Subject: [PATCH] A64/PopRSBHint: Prevent RETing to a guest PC of ~0ull from
 crashing the jit

---
 src/backend_x64/a64_emit_x64.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/backend_x64/a64_emit_x64.cpp b/src/backend_x64/a64_emit_x64.cpp
index 70e41b28..c290c849 100644
--- a/src/backend_x64/a64_emit_x64.cpp
+++ b/src/backend_x64/a64_emit_x64.cpp
@@ -1005,7 +1005,8 @@ void A64EmitX64::EmitTerminalImpl(IR::Term::LinkBlockFast terminal, IR::Location
 void A64EmitX64::EmitTerminalImpl(IR::Term::PopRSBHint, IR::LocationDescriptor) {
     // This calculation has to match up with A64::LocationDescriptor::UniqueHash
     // TODO: Optimization is available here based on known state of FPSCR_mode and CPSR_et.
-    code.mov(rcx, qword[r15 + offsetof(A64JitState, pc)]);
+    code.mov(rcx, A64::LocationDescriptor::PC_MASK);
+    code.and_(rcx, qword[r15 + offsetof(A64JitState, pc)]);
     code.mov(ebx, dword[r15 + offsetof(A64JitState, fpcr)]);
     code.and_(ebx, A64::LocationDescriptor::FPCR_MASK);
     code.shl(ebx, 37);