LibJS: Remove all interactions between Assembler and BasicBlock

With this change, Assembler is now free from LibJS concepts and could
move out to its own apartment. :^)

Userland/Libraries/LibJS/Bytecode/BasicBlock.h

@@ -43,19 +43,6 @@ public:
 
     DeprecatedString const& name() const { return m_name; }
 
-    // ==============================================================
-    // FIXME: This is JIT state and shouldn't be part of BasicBlock itself.
-
-    // Offset into the instruction stream where this code block starts.
-    size_t offset { 0 };
-
-    // Offsets into the instruction stream where we have RIP-relative jump offsets to here that need patching.
-    Vector<size_t> jumps_to_here;
-
-    // Offsets into the instruction stream where we have absolute 64-bit references to here that need patching.
-    Vector<size_t> absolute_references_to_here;
-    // ==============================================================
-
 private:
     explicit BasicBlock(DeprecatedString name);
 

Userland/Libraries/LibJS/JIT/Assembler.h

@@ -7,7 +7,6 @@
 #pragma once
 
 #include <AK/Vector.h>
-#include <LibJS/Bytecode/BasicBlock.h>
 
 namespace JS::JIT {
 
@@ -247,33 +246,6 @@ struct Assembler {
         emit8(0x0b);
     }
 
-    void jump(Bytecode::BasicBlock& target)
-    {
-        // jmp target (RIP-relative 32-bit offset)
-        emit8(0xe9);
-        target.jumps_to_here.append(m_output.size());
-        emit32(0xdeadbeef);
-    }
-
-    void jump_conditional(Reg reg, Bytecode::BasicBlock& true_target, Bytecode::BasicBlock& false_target)
-    {
-        // if (reg & 1) is 0, jump to false_target, else jump to true_target
-        // test reg, 1
-        emit8(0x48 | ((to_underlying(reg) >= 8) ? 1 << 2 : 0));
-        emit8(0xf7);
-        emit8(0xc0 | encode_reg(reg));
-        emit32(0x01);
-
-        // jz false_target (RIP-relative 32-bit offset)
-        emit8(0x0f);
-        emit8(0x84);
-        false_target.jumps_to_here.append(m_output.size());
-        emit32(0xdeadbeef);
-
-        // jmp true_target (RIP-relative 32-bit offset)
-        jump(true_target);
-    }
-
     void cmp(Operand lhs, Operand rhs)
     {
         if (lhs.type == Operand::Type::Reg && rhs.type == Operand::Type::Reg) {