Don't create excessive NilLiteralNode at parameters translation

andrykonchin · andrykonchin · commit da2f42368c58 · 2023-11-15T12:33:27.000+02:00
diff --git a/spec/truffle/parsing/fixtures/block/argument_descriptors/with_implicit_rest_parameter.yaml b/spec/truffle/parsing/fixtures/block/argument_descriptors/with_implicit_rest_parameter.yaml
@@ -203,30 +203,6 @@ ast: |
                                                                                           flags = 0
                                                                                           frameSlot = 3
                                                                                           type = FRAME_LOCAL
-                                                          IfElseNodeGen
-                                                              attributes:
-                                                                  flags = 0
-                                                              children:
-                                                                  condition =
-                                                                      ArrayIsAtLeastAsLargeAsNode
-                                                                          attributes:
-                                                                              flags = 0
-                                                                              requiredSize = 1
-                                                                          children:
-                                                                              child =
-                                                                                  ReadLocalVariableNode
-                                                                                      attributes:
-                                                                                          flags = 0
-                                                                                          frameSlot = 3
-                                                                                          type = FRAME_LOCAL
-                                                                  elseBody =
-                                                                      NilLiteralNode
-                                                                          attributes:
-                                                                              flags = 0
-                                                                  thenBody =
-                                                                      NilLiteralNode
-                                                                          attributes:
-                                                                              flags = 0
                                                       ]
                                   NilLiteralNode
                                       attributes:
diff --git a/spec/truffle/parsing/fixtures/block/argument_descriptors/with_numbered_parameters.yaml b/spec/truffle/parsing/fixtures/block/argument_descriptors/with_numbered_parameters.yaml
@@ -279,9 +279,6 @@ ast: |
                                                                                           flags = 0
                                                                                           frameSlot = 2
                                                                                           type = FRAME_LOCAL
-                                                          NilLiteralNode
-                                                              attributes:
-                                                                  flags = 0
                                                       ]
                                   ReadLocalVariableNode
                                       attributes:
diff --git a/spec/truffle/parsing/fixtures/block/argument_descriptors/with_optional_positional_parameters.yaml b/spec/truffle/parsing/fixtures/block/argument_descriptors/with_optional_positional_parameters.yaml
@@ -291,9 +291,6 @@ ast: |
                                                                                                       flags = 0
                                                                                                       frameSlot = 4
                                                                                                       type = FRAME_LOCAL
-                                                          NilLiteralNode
-                                                              attributes:
-                                                                  flags = 0
                                                       ]
                                   NilLiteralNode
                                       attributes:
diff --git a/spec/truffle/parsing/fixtures/block/argument_descriptors/with_positional_parameters.yaml b/spec/truffle/parsing/fixtures/block/argument_descriptors/with_positional_parameters.yaml
@@ -245,9 +245,6 @@ ast: |
                                                                                           flags = 0
                                                                                           frameSlot = 4
                                                                                           type = FRAME_LOCAL
-                                                          NilLiteralNode
-                                                              attributes:
-                                                                  flags = 0
                                                       ]
                                   NilLiteralNode
                                       attributes:
diff --git a/spec/truffle/parsing/fixtures/block/arity/with_implicit_rest_parameter.yaml b/spec/truffle/parsing/fixtures/block/arity/with_implicit_rest_parameter.yaml
@@ -203,30 +203,6 @@ ast: |
                                                                                           flags = 0
                                                                                           frameSlot = 3
                                                                                           type = FRAME_LOCAL
-                                                          IfElseNodeGen
-                                                              attributes:
-                                                                  flags = 0
-                                                              children:
-                                                                  condition =
-                                                                      ArrayIsAtLeastAsLargeAsNode
-                                                                          attributes:
-                                                                              flags = 0
-                                                                              requiredSize = 1
-                                                                          children:
-                                                                              child =
-                                                                                  ReadLocalVariableNode
-                                                                                      attributes:
-                                                                                          flags = 0
-                                                                                          frameSlot = 3
-                                                                                          type = FRAME_LOCAL
-                                                                  elseBody =
-                                                                      NilLiteralNode
-                                                                          attributes:
-                                                                              flags = 0
-                                                                  thenBody =
-                                                                      NilLiteralNode
-                                                                          attributes:
-                                                                              flags = 0
                                                       ]
                                   NilLiteralNode
                                       attributes:
diff --git a/spec/truffle/parsing/fixtures/block/arity/with_numbered_parameters.yaml b/spec/truffle/parsing/fixtures/block/arity/with_numbered_parameters.yaml
@@ -284,9 +284,6 @@ ast: |
                                                                                           flags = 0
                                                                                           frameSlot = 2
                                                                                           type = FRAME_LOCAL
-                                                          NilLiteralNode
-                                                              attributes:
-                                                                  flags = 0
                                                       ]
                                   ReadLocalVariableNode
                                       attributes:
diff --git a/spec/truffle/parsing/fixtures/block/arity/with_optional_positional_parameters.yaml b/spec/truffle/parsing/fixtures/block/arity/with_optional_positional_parameters.yaml
@@ -295,9 +295,6 @@ ast: |
                                                                                                       flags = 0
                                                                                                       frameSlot = 4
                                                                                                       type = FRAME_LOCAL
-                                                          NilLiteralNode
-                                                              attributes:
-                                                                  flags = 0
                                                       ]
                                   NilLiteralNode
                                       attributes:
diff --git a/spec/truffle/parsing/fixtures/block/arity/with_positional_parameters.yaml b/spec/truffle/parsing/fixtures/block/arity/with_positional_parameters.yaml
@@ -249,9 +249,6 @@ ast: |
                                                                                           flags = 0
                                                                                           frameSlot = 4
                                                                                           type = FRAME_LOCAL
-                                                          NilLiteralNode
-                                                              attributes:
-                                                                  flags = 0
                                                       ]
                                   NilLiteralNode
                                       attributes:
diff --git a/spec/truffle/parsing/fixtures/block/destructuring_array_argument/destructure/when_no_rest_positional_parameter_but_multiple_optional_ones.yaml b/spec/truffle/parsing/fixtures/block/destructuring_array_argument/destructure/when_no_rest_positional_parameter_but_multiple_optional_ones.yaml
@@ -284,30 +284,6 @@ ast: |
                                                                                                       flags = 0
                                                                                                       frameSlot = 3
                                                                                                       type = FRAME_LOCAL
-                                                          IfElseNodeGen
-                                                              attributes:
-                                                                  flags = 0
-                                                              children:
-                                                                  condition =
-                                                                      ArrayIsAtLeastAsLargeAsNode
-                                                                          attributes:
-                                                                              flags = 0
-                                                                              requiredSize = 0
-                                                                          children:
-                                                                              child =
-                                                                                  ReadLocalVariableNode
-                                                                                      attributes:
-                                                                                          flags = 0
-                                                                                          frameSlot = 3
-                                                                                          type = FRAME_LOCAL
-                                                                  elseBody =
-                                                                      NilLiteralNode
-                                                                          attributes:
-                                                                              flags = 0
-                                                                  thenBody =
-                                                                      NilLiteralNode
-                                                                          attributes:
-                                                                              flags = 0
                                                       ]
                                   NilLiteralNode
                                       attributes:
diff --git a/spec/truffle/parsing/fixtures/block/destructuring_array_argument/destructure/when_no_rest_positional_parameter_but_multiple_required_ones.yaml b/spec/truffle/parsing/fixtures/block/destructuring_array_argument/destructure/when_no_rest_positional_parameter_but_multiple_required_ones.yaml
@@ -229,9 +229,6 @@ ast: |
                                                                                           flags = 0
                                                                                           frameSlot = 3
                                                                                           type = FRAME_LOCAL
-                                                          NilLiteralNode
-                                                              attributes:
-                                                                  flags = 0
                                                       ]
                                   NilLiteralNode
                                       attributes:
diff --git a/spec/truffle/parsing/fixtures/block/destructuring_array_argument/destructure/when_no_rest_positional_parameter_but_single_required_and_single_optional_one.yaml b/spec/truffle/parsing/fixtures/block/destructuring_array_argument/destructure/when_no_rest_positional_parameter_but_single_required_and_single_optional_one.yaml
@@ -256,9 +256,6 @@ ast: |
                                                                                                       flags = 0
                                                                                                       frameSlot = 3
                                                                                                       type = FRAME_LOCAL
-                                                          NilLiteralNode
-                                                              attributes:
-                                                                  flags = 0
                                                       ]
                                   NilLiteralNode
                                       attributes:
diff --git a/spec/truffle/parsing/fixtures/block/destructuring_array_argument/destructure/when_rest_positional_parameter_and_multiple_required_pre_ones.yaml b/spec/truffle/parsing/fixtures/block/destructuring_array_argument/destructure/when_rest_positional_parameter_and_multiple_required_pre_ones.yaml
@@ -265,30 +265,6 @@ ast: |
                                                                                           flags = 0
                                                                                           frameSlot = 4
                                                                                           type = FRAME_LOCAL
-                                                          IfElseNodeGen
-                                                              attributes:
-                                                                  flags = 0
-                                                              children:
-                                                                  condition =
-                                                                      ArrayIsAtLeastAsLargeAsNode
-                                                                          attributes:
-                                                                              flags = 0
-                                                                              requiredSize = 2
-                                                                          children:
-                                                                              child =
-                                                                                  ReadLocalVariableNode
-                                                                                      attributes:
-                                                                                          flags = 0
-                                                                                          frameSlot = 4
-                                                                                          type = FRAME_LOCAL
-                                                                  elseBody =
-                                                                      NilLiteralNode
-                                                                          attributes:
-                                                                              flags = 0
-                                                                  thenBody =
-                                                                      NilLiteralNode
-                                                                          attributes:
-                                                                              flags = 0
                                                       ]
                                   NilLiteralNode
                                       attributes:
diff --git a/spec/truffle/parsing/fixtures/block/parameters_to_local_variables/with_numbered_parameters.yaml b/spec/truffle/parsing/fixtures/block/parameters_to_local_variables/with_numbered_parameters.yaml
@@ -322,9 +322,6 @@ ast: |
                                                                                           flags = 0
                                                                                           frameSlot = 2
                                                                                           type = FRAME_LOCAL
-                                                          NilLiteralNode
-                                                              attributes:
-                                                                  flags = 0
                                                       ]
                                   ReadLocalVariableNode
                                       attributes:
diff --git a/spec/truffle/parsing/fixtures/block/parameters_to_local_variables/with_optional_positional_parameters.yaml b/spec/truffle/parsing/fixtures/block/parameters_to_local_variables/with_optional_positional_parameters.yaml
@@ -294,9 +294,6 @@ ast: |
                                                                                                       flags = 0
                                                                                                       frameSlot = 4
                                                                                                       type = FRAME_LOCAL
-                                                          NilLiteralNode
-                                                              attributes:
-                                                                  flags = 0
                                                       ]
                                   NilLiteralNode
                                       attributes:
diff --git a/spec/truffle/parsing/fixtures/block/parameters_to_local_variables/with_positional_parameters.yaml b/spec/truffle/parsing/fixtures/block/parameters_to_local_variables/with_positional_parameters.yaml
@@ -249,9 +249,6 @@ ast: |
                                                                                           flags = 0
                                                                                           frameSlot = 4
                                                                                           type = FRAME_LOCAL
-                                                          NilLiteralNode
-                                                              attributes:
-                                                                  flags = 0
                                                       ]
                                   NilLiteralNode
                                       attributes:
diff --git a/src/main/java/org/truffleruby/parser/LoadArgumentsTranslator.java b/src/main/java/org/truffleruby/parser/LoadArgumentsTranslator.java
@@ -217,12 +217,16 @@ public RubyNode translate() {
 
         if (useArray()) {
             if (argsNode.getPreCount() == 0 || argsNode.hasRestArg()) {
-                sequence.add(IfElseNodeGen.create(
-                        new ArrayIsAtLeastAsLargeAsNode(required, loadArray(sourceSection)),
-                        notNilAtLeastAsLarge,
-                        notNilSmaller));
+                if (!notNilAtLeastAsLargeSequence.isEmpty() || !notNilSmallerSequence.isEmpty()) { // don't add 'if () then nil else nil';
+                    sequence.add(IfElseNodeGen.create(
+                            new ArrayIsAtLeastAsLargeAsNode(required, loadArray(sourceSection)),
+                            notNilAtLeastAsLarge,
+                            notNilSmaller));
+                }
             } else {
-                sequence.add(noRest);
+                if (!noRestSequence.isEmpty()) { // prevent adding NilLiteralNode
+                    sequence.add(noRest);
+                }
             }
         } else {
             // TODO CS 10-Jan-16 needn't have created notNilSmaller
