[Lldb-commits] [lldb] [lldb] Add a compiler/interpreter of LLDB data formatter bytecode to lldb/examples (PR #113398)

[Cassie Jones via lldb-commits]

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@@ -0,0 +1,486 @@
+"""
+Specification, compiler, disassembler, and interpreter
+for LLDB dataformatter bytecode.
+
+See formatter-bytecode.md for more details.
+"""
+from __future__ import annotations
+
+# Types
+type_String = 1
+type_Int = 2
+type_UInt = 3
+type_Object = 4
+type_Type = 5
+
+# Opcodes
+opcode = dict()
+
+
+def define_opcode(n, mnemonic, name):
+    globals()["op_" + name] = n
+    if mnemonic:
+        opcode[mnemonic] = n
+    opcode[n] = mnemonic
+
+
+define_opcode(1, "dup", "dup")
+define_opcode(2, "drop", "drop")
+define_opcode(3, "pick", "pick")
+define_opcode(4, "over", "over")
+define_opcode(5, "swap", "swap")
+define_opcode(6, "rot", "rot")
+
+define_opcode(0x10, "{", "begin")
+define_opcode(0x11, "if", "if")
+define_opcode(0x12, "ifelse", "ifelse")
+
+define_opcode(0x20, None, "lit_uint")
+define_opcode(0x21, None, "lit_int")
+define_opcode(0x22, None, "lit_string")
+define_opcode(0x23, None, "lit_selector")
+
+define_opcode(0x30, "+", "plus")
+define_opcode(0x31, "-", "minus")
+define_opcode(0x32, "*", "mul")
+define_opcode(0x33, "/", "div")
+define_opcode(0x34, "%", "mod")
+define_opcode(0x35, "<<", "shl")
+define_opcode(0x36, ">>", "shr")
+define_opcode(0x37, "shra", "shra")
----------------
porglezomp wrote:

Left shift doesn't have distinct arithmetic and logical shifts, they both always shift 0s into the bottom bit. If you look at instruction sets you'll see that generally just have these 3 operations.

https://github.com/llvm/llvm-project/pull/113398