From ace7ec4afc43c1bb15f9f63fa2b9acd560554c0d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alexander=20Mei=C3=9Fner?= <AlexanderMeissner@gmx.net>
Date: Fri, 3 Jan 2025 00:06:40 +0100
Subject: [PATCH] Revert "Refactor - Sanitization of memory accesses in JIT
 (#6)" (#14)

cad781a3b8f148e1421c706ee2e1bd765f80b437
---
 src/jit.rs | 18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/src/jit.rs b/src/jit.rs
index 78bbea34b..387dd9022 100644
--- a/src/jit.rs
+++ b/src/jit.rs
@@ -1169,16 +1169,12 @@ impl<'a, C: ContextObject> JitCompiler<'a, C> {
 
         match vm_addr {
             Value::RegisterPlusConstant64(reg, constant, user_provided) => {
-                debug_assert!(user_provided);
-                // First half of emit_sanitized_load_immediate(REGISTER_SCRATCH, vm_addr)
-                let lower_key = self.immediate_value_key as i32 as i64;
-                self.emit_ins(X86Instruction::lea(OperandSize::S64, reg, REGISTER_SCRATCH, Some(
-                    if reg == R12 {
-                        X86IndirectAccess::OffsetIndexShift(constant.wrapping_sub(lower_key) as i32, RSP, 0)
-                    } else {
-                        X86IndirectAccess::Offset(constant.wrapping_sub(lower_key) as i32)
-                    }
-                )));
+                if user_provided && self.should_sanitize_constant(constant) {
+                    self.emit_sanitized_load_immediate(REGISTER_SCRATCH, constant);
+                } else {
+                    self.emit_ins(X86Instruction::load_immediate(REGISTER_SCRATCH, constant));
+                }
+                self.emit_ins(X86Instruction::alu(OperandSize::S64, 0x01, reg, REGISTER_SCRATCH, None));
             },
             _ => {
                 #[cfg(debug_assertions)]
@@ -1597,8 +1593,6 @@ impl<'a, C: ContextObject> JitCompiler<'a, C> {
         ] {
             let target_offset = *anchor_base + len.trailing_zeros() as usize;
             self.set_anchor(ANCHOR_TRANSLATE_MEMORY_ADDRESS + target_offset);
-            // Second half of emit_sanitized_load_immediate(REGISTER_SCRATCH, vm_addr)
-            self.emit_ins(X86Instruction::alu_immediate(OperandSize::S64, 0x81, 0, REGISTER_SCRATCH, lower_key, None));
             // call MemoryMapping::(load|store) storing the result in RuntimeEnvironmentSlot::ProgramResult
             if *anchor_base == 0 { // AccessType::Load
                 let load = match len {