gh-107901: compiler replaces POP_BLOCK instruction by NOPs before optimisations (#114530)

iritkatriel · web-flow · commit ac5e53e15057 · 2024-01-25T20:06:48.000Z
diff --git a/Python/flowgraph.c b/Python/flowgraph.c
@@ -903,6 +903,7 @@ label_exception_targets(basicblock *entryblock) {
             }
             else if (instr->i_opcode == POP_BLOCK) {
                 handler = pop_except_block(except_stack);
+                INSTR_SET_OP0(instr, NOP);
             }
             else if (is_jump(instr)) {
                 instr->i_except = handler;
@@ -2313,7 +2314,7 @@ convert_pseudo_ops(cfg_builder *g)
     for (basicblock *b = entryblock; b != NULL; b = b->b_next) {
         for (int i = 0; i < b->b_iused; i++) {
             cfg_instr *instr = &b->b_instr[i];
-            if (is_block_push(instr) || instr->i_opcode == POP_BLOCK) {
+            if (is_block_push(instr)) {
                 INSTR_SET_OP0(instr, NOP);
             }
             else if (instr->i_opcode == LOAD_CLOSURE) {

Original file line number	Diff line number	Diff line change
`@@ -903,6 +903,7 @@ label_exception_targets(basicblock *entryblock) {`
`903`	`903`	`}`
`904`	`904`	`else if (instr->i_opcode == POP_BLOCK) {`
`905`	`905`	`handler = pop_except_block(except_stack);`
	`906`	`+ INSTR_SET_OP0(instr, NOP);`
`906`	`907`	`}`
`907`	`908`	`else if (is_jump(instr)) {`
`908`	`909`	`instr->i_except = handler;`
`@@ -2313,7 +2314,7 @@ convert_pseudo_ops(cfg_builder *g)`
`2313`	`2314`	`for (basicblock *b = entryblock; b != NULL; b = b->b_next) {`
`2314`	`2315`	`for (int i = 0; i < b->b_iused; i++) {`
`2315`	`2316`	`cfg_instr *instr = &b->b_instr[i];`
`2316`		`- if (is_block_push(instr) \|\| instr->i_opcode == POP_BLOCK) {`
	`2317`	`+ if (is_block_push(instr)) {`
`2317`	`2318`	`INSTR_SET_OP0(instr, NOP);`
`2318`	`2319`	`}`
`2319`	`2320`	`else if (instr->i_opcode == LOAD_CLOSURE) {`