[compiler-v2] Fix issue with autoref of variant field selection (#14312)

Fixes #14300

When recently introducing the new VariantField selection ops, the logic for autoref for such operations wasn't updated.

Adds the test from the bug, as well as moves another test already failing earlier into bytecode generator test suite. Also completes the test to ensure all scenarios of variant field selection update are covered. Adds that test also to transactional test to ensure correct execution behavior.

third_party/move/move-compiler-v2/src/bytecode_generator.rs

@@ -1089,7 +1089,9 @@ impl<'env> Generator<'env> {
         match exp.as_ref() {
             ExpData::Temporary(_, temp) if !with_forced_temp => *temp,
             ExpData::LocalVar(id, sym) if !with_forced_temp => self.find_local(*id, *sym),
-            ExpData::Call(id, Operation::Select(..), _) if self.reference_mode() => {
+            ExpData::Call(id, Operation::Select(..) | Operation::SelectVariants(..), _)
+                if self.reference_mode() =>
+            {
                 // In reference mode, a selection is interpreted as selecting a reference to the
                 // field.
                 let ty =

third_party/move/move-compiler-v2/tests/bytecode-generator/bug_14300_update_variant_select.exp

@@ -0,0 +1,149 @@
+// -- Model dump before bytecode pipeline
+module 0x815::m {
+    enum CommonFields {
+        Foo {
+            x: u64,
+            y: u8,
+        }
+        Bar {
+            x: u64,
+            y: u8,
+            z: u32,
+        }
+        Baz {
+            y: u8,
+        }
+    }
+    private fun update_common_field(): u64 {
+        {
+          let common: m::CommonFields = pack m::CommonFields::Bar(30, 40, 50);
+          select_variants m::CommonFields.Foo.x|m::CommonFields.Bar.x<m::CommonFields>(common) = 15;
+          select_variants m::CommonFields.Foo.x|m::CommonFields.Bar.x<m::CommonFields>(common)
+        }
+    }
+    private fun update_common_field_different_offset(): u8 {
+        {
+          let common: m::CommonFields = pack m::CommonFields::Bar(30, 40, 50);
+          select_variants m::CommonFields.Foo.y|m::CommonFields.Bar.y|m::CommonFields.Baz.y<m::CommonFields>(common) = 15;
+          select_variants m::CommonFields.Foo.y|m::CommonFields.Bar.y|m::CommonFields.Baz.y<m::CommonFields>(common)
+        }
+    }
+    private fun update_non_common_field(): u32 {
+        {
+          let common: m::CommonFields = pack m::CommonFields::Bar(30, 40, 50);
+          select_variants m::CommonFields.Bar.z<m::CommonFields>(common) = 15;
+          select_variants m::CommonFields.Bar.z<m::CommonFields>(common)
+        }
+    }
+} // end 0x815::m
+
+============ initial bytecode ================
+
+[variant baseline]
+fun m::update_common_field(): u64 {
+     var $t0: u64
+     var $t1: m::CommonFields
+     var $t2: u64
+     var $t3: u8
+     var $t4: u32
+     var $t5: u64
+     var $t6: &mut u64
+     var $t7: &mut m::CommonFields
+     var $t8: &m::CommonFields
+     var $t9: &u64
+  0: $t2 := 30
+  1: $t3 := 40
+  2: $t4 := 50
+  3: $t1 := pack_variant m::CommonFields::Bar($t2, $t3, $t4)
+  4: $t5 := 15
+  5: $t7 := borrow_local($t1)
+  6: $t6 := borrow_variant_field<m::CommonFields::Foo|Bar>.x($t7)
+  7: write_ref($t6, $t5)
+  8: $t8 := borrow_local($t1)
+  9: $t9 := borrow_variant_field<m::CommonFields::Foo|Bar>.x($t8)
+ 10: $t0 := read_ref($t9)
+ 11: return $t0
+}
+
+
+[variant baseline]
+fun m::update_common_field_different_offset(): u8 {
+     var $t0: u8
+     var $t1: m::CommonFields
+     var $t2: u64
+     var $t3: u8
+     var $t4: u32
+     var $t5: u8
+     var $t6: &mut u8
+     var $t7: &mut m::CommonFields
+     var $t8: bool
+     var $t9: &m::CommonFields
+     var $t10: &u8
+     var $t11: bool
+  0: $t2 := 30
+  1: $t3 := 40
+  2: $t4 := 50
+  3: $t1 := pack_variant m::CommonFields::Bar($t2, $t3, $t4)
+  4: $t5 := 15
+  5: $t7 := borrow_local($t1)
+  6: $t8 := test_variant m::CommonFields::Foo($t7)
+  7: if ($t8) goto 13 else goto 8
+  8: label L3
+  9: $t8 := test_variant m::CommonFields::Bar($t7)
+ 10: if ($t8) goto 13 else goto 11
+ 11: label L4
+ 12: goto 16
+ 13: label L2
+ 14: $t6 := borrow_variant_field<m::CommonFields::Foo|Bar>.y($t7)
+ 15: goto 18
+ 16: label L1
+ 17: $t6 := borrow_variant_field<m::CommonFields::Baz>.y($t7)
+ 18: label L0
+ 19: write_ref($t6, $t5)
+ 20: $t9 := borrow_local($t1)
+ 21: $t11 := test_variant m::CommonFields::Foo($t9)
+ 22: if ($t11) goto 28 else goto 23
+ 23: label L8
+ 24: $t11 := test_variant m::CommonFields::Bar($t9)
+ 25: if ($t11) goto 28 else goto 26
+ 26: label L9
+ 27: goto 31
+ 28: label L7
+ 29: $t10 := borrow_variant_field<m::CommonFields::Foo|Bar>.y($t9)
+ 30: goto 33
+ 31: label L6
+ 32: $t10 := borrow_variant_field<m::CommonFields::Baz>.y($t9)
+ 33: label L5
+ 34: $t0 := read_ref($t10)
+ 35: return $t0
+}
+
+
+[variant baseline]
+fun m::update_non_common_field(): u32 {
+     var $t0: u32
+     var $t1: m::CommonFields
+     var $t2: u64
+     var $t3: u8
+     var $t4: u32
+     var $t5: u32
+     var $t6: &mut u32
+     var $t7: &mut m::CommonFields
+     var $t8: &m::CommonFields
+     var $t9: &u32
+  0: $t2 := 30
+  1: $t3 := 40
+  2: $t4 := 50
+  3: $t1 := pack_variant m::CommonFields::Bar($t2, $t3, $t4)
+  4: $t5 := 15
+  5: $t7 := borrow_local($t1)
+  6: $t6 := borrow_variant_field<m::CommonFields::Bar>.z($t7)
+  7: write_ref($t6, $t5)
+  8: $t8 := borrow_local($t1)
+  9: $t9 := borrow_variant_field<m::CommonFields::Bar>.z($t8)
+ 10: $t0 := read_ref($t9)
+ 11: return $t0
+}
+
+
+============ bytecode verification succeeded ========

third_party/move/move-compiler-v2/tests/bytecode-generator/bug_14300_update_variant_select.move

@@ -0,0 +1,38 @@
+module 0x815::m {
+
+    enum CommonFields has drop {
+      Foo{x: u64, y: u8},
+      Bar{x: u64, y: u8, z: u32}
+      Baz{y: u8}
+    }
+
+    fun update_common_field(): u64 {
+        let common = CommonFields::Bar {
+            x: 30,
+            y: 40,
+            z: 50
+        };
+        common.x = 15;
+        common.x
+    }
+
+    fun update_non_common_field(): u32 {
+        let common = CommonFields::Bar {
+            x: 30,
+            y: 40,
+            z: 50
+        };
+        common.z = 15;
+        common.z
+    }
+
+    fun update_common_field_different_offset(): u8 {
+        let common = CommonFields::Bar {
+            x: 30,
+            y: 40,
+            z: 50
+        };
+        common.y = 15;
+        common.y
+    }
+}

third_party/move/move-compiler-v2/tests/bytecode-generator/bug_14300_variant_select_autoref.exp

@@ -0,0 +1,41 @@
+// -- Model dump before bytecode pipeline
+module 0x815::m {
+    enum Positional {
+        A {
+            0: u8,
+        }
+        B {
+            0: u8,
+        }
+    }
+    private fun test_common_access(): u8 {
+        {
+          let x: m::Positional = pack m::Positional::A(42);
+          select_variants m::Positional.A.0|m::Positional.B.0<m::Positional>(x) = 19;
+          20
+        }
+    }
+} // end 0x815::m
+
+============ initial bytecode ================
+
+[variant baseline]
+fun m::test_common_access(): u8 {
+     var $t0: u8
+     var $t1: m::Positional
+     var $t2: u8
+     var $t3: u8
+     var $t4: &mut u8
+     var $t5: &mut m::Positional
+  0: $t2 := 42
+  1: $t1 := pack_variant m::Positional::A($t2)
+  2: $t3 := 19
+  3: $t5 := borrow_local($t1)
+  4: $t4 := borrow_variant_field<m::Positional::A|B>.0($t5)
+  5: write_ref($t4, $t3)
+  6: $t0 := 20
+  7: return $t0
+}
+
+
+============ bytecode verification succeeded ========

third_party/move/move-compiler-v2/tests/bytecode-generator/bug_14300_variant_select_autoref.move

@@ -0,0 +1,13 @@
+module 0x815::m {
+
+    enum Positional has drop {
+        A(u8),
+        B(u8),
+    }
+    fun test_common_access(): u8 {
+        let x = Positional::A(42);
+        x.0 = 19;
+        20
+    }
+
+}

third_party/move/move-compiler-v2/transactional-tests/tests/no-v1-comparison/enum/bug_14300_update_variant_field.exp

@@ -0,0 +1,10 @@
+processed 4 tasks
+
+task 1 'run'. lines 41-41:
+return values: 15
+
+task 2 'run'. lines 43-43:
+return values: 15
+
+task 3 'run'. lines 45-45:
+return values: 15

third_party/move/move-compiler-v2/transactional-tests/tests/no-v1-comparison/enum/bug_14300_update_variant_field.move

@@ -0,0 +1,45 @@
+//# publish
+module 0x815::m {
+
+    enum CommonFields has drop {
+      Foo{x: u64, y: u8},
+      Bar{x: u64, y: u8, z: u32}
+      Baz{y: u8}
+    }
+
+    fun update_common_field(): u64 {
+        let common = CommonFields::Bar {
+            x: 30,
+            y: 40,
+            z: 50
+        };
+        common.x = 15;
+        common.x
+    }
+
+    fun update_non_common_field(): u32 {
+        let common = CommonFields::Bar {
+            x: 30,
+            y: 40,
+            z: 50
+        };
+        common.z = 15;
+        common.z
+    }
+
+    fun update_common_field_different_offset(): u8 {
+        let common = CommonFields::Bar {
+            x: 30,
+            y: 40,
+            z: 50
+        };
+        common.y = 15;
+        common.y
+    }
+}
+
+//# run 0x815::m::update_common_field
+
+//# run 0x815::m::update_non_common_field
+
+//# run 0x815::m::update_common_field_different_offset