GH-105229: Remove remaining two-codeunit superinstructions (GH-105326)

* Remove LOAD_CONST__LOAD_FAST and LOAD_FAST__LOAD_CONST superinstructions.

Author: markshannon

Include/internal/pycore_opcode.h

@@ -55,11 +55,6 @@ extern "C" {
          (opcode) == RAISE_VARARGS || \
          (opcode) == RERAISE)
 
-#define IS_SUPERINSTRUCTION_OPCODE(opcode) \
-        ((opcode) == LOAD_FAST__LOAD_CONST || \
-         (opcode) == LOAD_CONST__LOAD_FAST)
-
-
 #define LOG_BITS_PER_INT 5
 #define MASK_LOW_LOG_BITS 31
 

Include/internal/pycore_opcode_utils.h

@@ -409,12 +409,6 @@ def pseudo_op(name, op, real_ops):
         "LOAD_ATTR_METHOD_NO_DICT",
         "LOAD_ATTR_METHOD_WITH_VALUES",
     ],
-    "LOAD_CONST": [
-        "LOAD_CONST__LOAD_FAST",
-    ],
-    "LOAD_FAST": [
-        "LOAD_FAST__LOAD_CONST",
-    ],
     "LOAD_GLOBAL": [
         "LOAD_GLOBAL_BUILTIN",
         "LOAD_GLOBAL_MODULE",

Include/opcode.h

@@ -0,0 +1,3 @@
+Remove remaining two-codeunit superinstructions. All remaining
+superinstructions only take a single codeunit, simplifying instrumentation
+and quickening.

Lib/opcode.py

@@ -233,9 +233,6 @@ dummy_func(
             SETLOCAL(oparg2, value2);
         }
 
-        super(LOAD_FAST__LOAD_CONST) = LOAD_FAST + LOAD_CONST;
-        super(LOAD_CONST__LOAD_FAST) = LOAD_CONST + LOAD_FAST;
-
         inst(POP_TOP, (value --)) {
             DECREF_INPUTS();
         }

Misc/NEWS.d/next/Core and Builtins/2023-06-03-04-28-28.gh-issue-105229.stEmfp.rst

@@ -1676,7 +1676,6 @@ scan_block_for_locals(basicblock *b, basicblock ***sp)
     for (int i = 0; i < b->b_iused; i++) {
         cfg_instr *instr = &b->b_instr[i];
         assert(instr->i_opcode != EXTENDED_ARG);
-        assert(!IS_SUPERINSTRUCTION_OPCODE(instr->i_opcode));
         if (instr->i_except != NULL) {
             maybe_push(instr->i_except, unsafe_mask, sp);
         }
@@ -1735,7 +1734,6 @@ fast_scan_many_locals(basicblock *entryblock, int nlocals)
         for (int i = 0; i < b->b_iused; i++) {
             cfg_instr *instr = &b->b_instr[i];
             assert(instr->i_opcode != EXTENDED_ARG);
-            assert(!IS_SUPERINSTRUCTION_OPCODE(instr->i_opcode));
             int arg = instr->i_oparg;
             if (arg < 64) {
                 continue;