From 4797a0dd2b933c44fa21e534913b4541119c73aa Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alexander=20Mei=C3=9Fner?= <AlexanderMeissner@gmx.net>
Date: Wed, 25 Sep 2024 09:17:53 +0200
Subject: [PATCH] Removes REGISTER_OTHER_SCRATCH from
 ANCHOR_ANCHOR_INTERNAL_FUNCTION_CALL_REG.

---
 src/jit.rs | 5 ++---
 src/x86.rs | 1 +
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/jit.rs b/src/jit.rs
index 0a618260..d58a5900 100644
--- a/src/jit.rs
+++ b/src/jit.rs
@@ -1508,9 +1508,8 @@ impl<'a, C: ContextObject> JitCompiler<'a, C> {
         // Load the frame pointer again since we've clobbered REGISTER_MAP[FRAME_PTR_REG]
         self.emit_ins(X86Instruction::load(OperandSize::S64, REGISTER_PTR_TO_VM, REGISTER_MAP[FRAME_PTR_REG], stack_pointer_access));
         // Restore the clobbered REGISTER_MAP[0]
-        self.emit_ins(X86Instruction::mov(OperandSize::S64, REGISTER_MAP[0], REGISTER_OTHER_SCRATCH));
-        self.emit_ins(X86Instruction::pop(REGISTER_MAP[0]));
-        self.emit_ins(X86Instruction::jump_reg(REGISTER_OTHER_SCRATCH, None)); // Tail call to host_target_address
+        self.emit_ins(X86Instruction::xchg(OperandSize::S64, REGISTER_MAP[0], RSP, Some(X86IndirectAccess::OffsetIndexShift(0, RSP, 0)))); // Swap REGISTER_MAP[0] and host_target_address
+        self.emit_ins(X86Instruction::return_near()); // Tail call to host_target_address
 
         // Translates a vm memory address to a host memory address
         for (access_type, len) in &[
diff --git a/src/x86.rs b/src/x86.rs
index b592f475..ccb2467b 100644
--- a/src/x86.rs
+++ b/src/x86.rs
@@ -614,6 +614,7 @@ impl X86Instruction {
     }
 
     /// Jump to absolute destination
+    #[allow(dead_code)]
     #[inline]
     pub const fn jump_reg(destination: u8, indirect: Option<X86IndirectAccess>) -> Self {
         Self {