Fix DCA warnings for log intrinsic and stdlib function (FuelLabs#3538)

This adds special handling for the log intrinsic, consuming the fields
of all structs used inside the inner expressions.

It also does the same for functions external to the current analysis, to
solve the same thing for the stdlib log function, which could lead to
some false negatives when it comes to the unused fields warning, but
it's the best we can do for now without considerable effort refactoring
the DCA engine to work inter-proceduraly/module.

Closes FuelLabs#3012.

Co-authored-by: Mohammad Fawaz <[email protected]>

sway-core/src/control_flow_analysis/flow_graph/namespace.rs

@@ -130,6 +130,9 @@ impl ControlFlowNamespace {
         }
     }
 
+    pub(crate) fn get_struct(&self, ident: &Ident) -> Option<&StructNamespaceEntry> {
+        self.struct_namespace.get(ident.as_str())
+    }
     pub(crate) fn insert_struct(
         &mut self,
         struct_name: String,

test/src/e2e_vm_tests/test_programs/should_pass/dca/log_intrinsic/Forc.lock

@@ -0,0 +1,3 @@
+[[package]]
+name = 'log'
+source = 'member'

test/src/e2e_vm_tests/test_programs/should_pass/dca/log_intrinsic/Forc.toml

@@ -0,0 +1,6 @@
+[project]
+authors = ["Fuel Labs <[email protected]>"]
+entry = "main.sw"
+license = "Apache-2.0"
+name = "log"
+implicit-std = false

test/src/e2e_vm_tests/test_programs/should_pass/dca/log_intrinsic/src/main.sw

@@ -0,0 +1,10 @@
+script;
+
+struct Foo {
+    value: u64
+}
+
+fn main() -> u64 {
+    __log(Foo {value: 0});
+    0
+}

test/src/e2e_vm_tests/test_programs/should_pass/dca/log_intrinsic/test.toml

@@ -0,0 +1,4 @@
+category = "compile"
+
+# not: $()value: u64
+# not: $()This struct field is never accessed.

test/src/e2e_vm_tests/test_programs/should_pass/dca/log_stdlib/Forc.lock

@@ -0,0 +1,13 @@
+[[package]]
+name = 'core'
+source = 'path+from-root-E6171879CB601FD9'
+
+[[package]]
+name = 'log_stdlib'
+source = 'member'
+dependencies = ['std']
+
+[[package]]
+name = 'std'
+source = 'path+from-root-E6171879CB601FD9'
+dependencies = ['core']

test/src/e2e_vm_tests/test_programs/should_pass/dca/log_stdlib/Forc.toml

@@ -0,0 +1,8 @@
+[project]
+authors = ["Fuel Labs <[email protected]>"]
+entry = "main.sw"
+license = "Apache-2.0"
+name = "log_stdlib"
+
+[dependencies]
+std = { path = "../../../../../../../sway-lib-std" }

test/src/e2e_vm_tests/test_programs/should_pass/dca/log_stdlib/src/main.sw

@@ -0,0 +1,12 @@
+script;
+
+use std::logging::log;
+
+struct Foo {
+    value: u64
+}
+
+fn main() -> u64 {
+    log(Foo {value: 0});
+    0
+}

test/src/e2e_vm_tests/test_programs/should_pass/dca/log_stdlib/test.toml

@@ -0,0 +1,4 @@
+category = "compile"
+
+# not: $()value: u64
+# not: $()This struct field is never accessed.

test/src/e2e_vm_tests/test_programs/should_pass/dca/unused_fields/Forc.lock

@@ -0,0 +1,3 @@
+[[package]]
+name = 'unused_fields'
+source = 'member'

test/src/e2e_vm_tests/test_programs/should_pass/dca/unused_fields/Forc.toml

@@ -0,0 +1,6 @@
+[project]
+authors = ["Fuel Labs <[email protected]>"]
+entry = "main.sw"
+license = "Apache-2.0"
+name = "unused_fields"
+implicit-std = false

test/src/e2e_vm_tests/test_programs/should_pass/dca/unused_fields/src/main.sw

@@ -0,0 +1,19 @@
+script;
+
+dep utils;
+use utils::Foo;
+
+
+struct Bar {
+    value: u64
+}
+
+fn internal_fn(s: Bar) {
+
+}
+
+fn main() -> u64 {
+    internal_fn(Bar {value: 0});
+    utils::external_fn(Foo {value: 0});
+    0
+}

test/src/e2e_vm_tests/test_programs/should_pass/dca/unused_fields/src/utils.sw

@@ -0,0 +1,9 @@
+library utils;
+
+pub struct Foo {
+    value: u64
+}
+
+pub fn external_fn(s: Foo) {
+
+}

test/src/e2e_vm_tests/test_programs/should_pass/dca/unused_fields/test.toml

@@ -0,0 +1,7 @@
+category = "compile"
+
+# check: $()struct Bar {
+# check: $()This struct field is never accessed.
+
+# not: $()value: u64
+# not: $()This struct field is never accessed.