update tests, call clear_nops() in remove_unused_variables

tests/unit/compiler/venom/test_memmerging.py

@@ -3,14 +3,15 @@
 from tests.venom_utils import assert_ctx_eq, parse_from_basic_block, parse_venom
 from vyper.evm.opcodes import version_check
 from vyper.venom.analysis import IRAnalysesCache
-from vyper.venom.passes import SCCP, MemMergePass
+from vyper.venom.passes import SCCP, MemMergePass, RemoveUnusedVariablesPass
 
 
 def _check_pre_post(pre, post):
     ctx = parse_from_basic_block(pre)
     for fn in ctx.functions.values():
         ac = IRAnalysesCache(fn)
         MemMergePass(ac, fn).run_pass()
+        RemoveUnusedVariablesPass(ac, fn).run_pass()
     assert_ctx_eq(ctx, parse_from_basic_block(post))
 
 
@@ -853,8 +854,6 @@ def test_memzeroing_2():
 
     post = """
     _global:
-        %1 = calldatasize
-        %2 = calldatasize
         %3 = calldatasize
         calldatacopy 64, %3, 256
         stop
@@ -881,8 +880,6 @@ def test_memzeroing_3():
 
     post = """
     _global:
-        %1 = calldatasize
-        %2 = calldatasize
         %3 = calldatasize
         calldatacopy 0, %3, 264
         stop
@@ -905,7 +902,6 @@ def test_memzeroing_small_calldatacopy():
 
     post = """
     _global:
-        %1 = calldatasize
         mstore 0, 0
         stop
     """
@@ -935,13 +931,8 @@ def test_memzeroing_smaller_calldatacopy():
 
     post = """
     _global:
-        %1 = calldatasize
-        %2 = calldatasize
         %6 = calldatasize
         calldatacopy 0, %6, 24
-        %3 = calldatasize
-        %4 = calldatasize
-        %5 = calldatasize
         mstore 100, 0
         stop
     """
@@ -966,7 +957,6 @@ def test_memzeroing_overlap():
 
     post = """
     _global:
-        %1 = calldatasize
         %2 = calldatasize
         calldatacopy 100, %2, 64
         stop

vyper/venom/basicblock.py

@@ -543,6 +543,10 @@ def insert_instruction(self, instruction: IRInstruction, index: Optional[int] =
         instruction.error_msg = self.parent.error_msg
         self.instructions.insert(index, instruction)
 
+    def clear_nops(self) -> None:
+        if any(inst.opcode == "nop" for inst in self.instructions):
+            self.instructions = [inst for inst in self.instructions if inst.opcode != "nop"]
+
     def remove_instruction(self, instruction: IRInstruction) -> None:
         assert isinstance(instruction, IRInstruction), "instruction must be an IRInstruction"
         self.instructions.remove(instruction)

vyper/venom/passes/remove_unused_variables.py

@@ -25,6 +25,9 @@ def run_pass(self):
             inst = work_list.pop()
             self._process_instruction(inst)
 
+        for bb in self.function.get_basic_blocks():
+            bb.clear_nops()
+
         self.analyses_cache.invalidate_analysis(LivenessAnalysis)
         self.analyses_cache.invalidate_analysis(DFGAnalysis)