From 75af3c58f9df479894465e81d374e047082e8789 Mon Sep 17 00:00:00 2001
From: Zalathar <Zalathar@users.noreply.github.com>
Date: Thu, 15 Feb 2024 13:58:21 +1100
Subject: [PATCH 1/2] coverage: Regression test for a span extraction
inconsistency
---
tests/coverage/closure_unit_return.cov-map | 34 +++++++++++++++++++++
tests/coverage/closure_unit_return.coverage | 30 ++++++++++++++++++
tests/coverage/closure_unit_return.rs | 29 ++++++++++++++++++
3 files changed, 93 insertions(+)
create mode 100644 tests/coverage/closure_unit_return.cov-map
create mode 100644 tests/coverage/closure_unit_return.coverage
create mode 100644 tests/coverage/closure_unit_return.rs
diff --git a/tests/coverage/closure_unit_return.cov-map b/tests/coverage/closure_unit_return.cov-map
new file mode 100644
index 0000000000000..330a6b420b0e2
--- /dev/null
+++ b/tests/coverage/closure_unit_return.cov-map
@@ -0,0 +1,34 @@
+Function name: closure_unit_return::explicit_unit
+Raw bytes (14): 0x[01, 01, 00, 02, 01, 07, 01, 01, 10, 01, 05, 05, 02, 02]
+Number of files: 1
+- file 0 => global file 1
+Number of expressions: 0
+Number of file 0 mappings: 2
+- Code(Counter(0)) at (prev + 7, 1) to (start + 1, 16)
+- Code(Counter(0)) at (prev + 5, 5) to (start + 2, 2)
+
+Function name: closure_unit_return::explicit_unit::{closure#0} (unused)
+Raw bytes (9): 0x[01, 01, 00, 01, 00, 08, 16, 02, 06]
+Number of files: 1
+- file 0 => global file 1
+Number of expressions: 0
+Number of file 0 mappings: 1
+- Code(Zero) at (prev + 8, 22) to (start + 2, 6)
+
+Function name: closure_unit_return::implicit_unit
+Raw bytes (14): 0x[01, 01, 00, 02, 01, 10, 01, 01, 13, 01, 03, 06, 04, 02]
+Number of files: 1
+- file 0 => global file 1
+Number of expressions: 0
+Number of file 0 mappings: 2
+- Code(Counter(0)) at (prev + 16, 1) to (start + 1, 19)
+- Code(Counter(0)) at (prev + 3, 6) to (start + 4, 2)
+
+Function name: closure_unit_return::implicit_unit::{closure#0} (unused)
+Raw bytes (9): 0x[01, 01, 00, 01, 00, 11, 16, 02, 06]
+Number of files: 1
+- file 0 => global file 1
+Number of expressions: 0
+Number of file 0 mappings: 1
+- Code(Zero) at (prev + 17, 22) to (start + 2, 6)
+
diff --git a/tests/coverage/closure_unit_return.coverage b/tests/coverage/closure_unit_return.coverage
new file mode 100644
index 0000000000000..1a706b3a18d66
--- /dev/null
+++ b/tests/coverage/closure_unit_return.coverage
@@ -0,0 +1,30 @@
+ LL| |#![feature(coverage_attribute)]
+ LL| |// edition: 2021
+ LL| |
+ LL| |// Regression test for an inconsistency between functions that return the value
+ LL| |// of their trailing expression, and functions that implicitly return `()`.
+ LL| |
+ LL| 1|fn explicit_unit() {
+ LL| 1| let closure = || {
+ LL| 0| ();
+ LL| 0| };
+ LL| |
+ LL| 1| drop(closure);
+ LL| 1| () // explicit return of trailing value
+ LL| 1|}
+ LL| |
+ LL| 1|fn implicit_unit() {
+ LL| 1| let closure = || {
+ LL| 0| ();
+ LL| 1| };
+ LL| 1|
+ LL| 1| drop(closure);
+ LL| 1| // implicit return of `()`
+ LL| 1|}
+ LL| |
+ LL| |#[coverage(off)]
+ LL| |fn main() {
+ LL| | explicit_unit();
+ LL| | implicit_unit();
+ LL| |}
+
diff --git a/tests/coverage/closure_unit_return.rs b/tests/coverage/closure_unit_return.rs
new file mode 100644
index 0000000000000..d2b4ab8bd9ff9
--- /dev/null
+++ b/tests/coverage/closure_unit_return.rs
@@ -0,0 +1,29 @@
+#![feature(coverage_attribute)]
+// edition: 2021
+
+// Regression test for an inconsistency between functions that return the value
+// of their trailing expression, and functions that implicitly return `()`.
+
+fn explicit_unit() {
+ let closure = || {
+ ();
+ };
+
+ drop(closure);
+ () // explicit return of trailing value
+}
+
+fn implicit_unit() {
+ let closure = || {
+ ();
+ };
+
+ drop(closure);
+ // implicit return of `()`
+}
+
+#[coverage(off)]
+fn main() {
+ explicit_unit();
+ implicit_unit();
+}
From cd9021e8cb1ab6cf5bdf341d7e0538703d86fc5b Mon Sep 17 00:00:00 2001
From: Zalathar <Zalathar@users.noreply.github.com>
Date: Thu, 15 Feb 2024 18:12:27 +1100
Subject: [PATCH 2/2] coverage: Discard spans that fill the entire function
body
When we try to extract coverage-relevant spans from MIR, sometimes we see MIR
statements/terminators whose spans cover the entire function body. Those spans
tend to be unhelpful for coverage purposes, because they often represent
compiler-inserted code, e.g. the implicit return value of `()`.
---
.../src/coverage/spans/from_mir.rs | 13 +++++++++----
tests/coverage/closure_unit_return.cov-map | 6 +++---
tests/coverage/closure_unit_return.coverage | 4 ++--
tests/coverage/coverage_attr_closure.cov-map | 8 ++++----
tests/coverage/coverage_attr_closure.coverage | 8 ++++----
tests/coverage/inline-dead.cov-map | 6 +++---
tests/coverage/macro_name_span.cov-map | 4 ++--
tests/coverage/macro_name_span.coverage | 2 +-
tests/coverage/unicode.cov-map | 8 --------
tests/coverage/unicode.coverage | 3 +--
10 files changed, 29 insertions(+), 33 deletions(-)
diff --git a/compiler/rustc_mir_transform/src/coverage/spans/from_mir.rs b/compiler/rustc_mir_transform/src/coverage/spans/from_mir.rs
index 9517ede288f5d..2db358379fe51 100644
--- a/compiler/rustc_mir_transform/src/coverage/spans/from_mir.rs
+++ b/compiler/rustc_mir_transform/src/coverage/spans/from_mir.rs
@@ -132,18 +132,23 @@ fn bcb_to_initial_coverage_spans<'a, 'tcx>(
bcb_data.basic_blocks.iter().flat_map(move |&bb| {
let data = &mir_body[bb];
+ let unexpand = move |expn_span| {
+ unexpand_into_body_span_with_visible_macro(expn_span, body_span)
+ // Discard any spans that fill the entire body, because they tend
+ // to represent compiler-inserted code, e.g. implicitly returning `()`.
+ .filter(|(span, _)| !span.source_equal(body_span))
+ };
+
let statement_spans = data.statements.iter().filter_map(move |statement| {
let expn_span = filtered_statement_span(statement)?;
- let (span, visible_macro) =
- unexpand_into_body_span_with_visible_macro(expn_span, body_span)?;
+ let (span, visible_macro) = unexpand(expn_span)?;
Some(SpanFromMir::new(span, visible_macro, bcb, is_closure_like(statement)))
});
let terminator_span = Some(data.terminator()).into_iter().filter_map(move |terminator| {
let expn_span = filtered_terminator_span(terminator)?;
- let (span, visible_macro) =
- unexpand_into_body_span_with_visible_macro(expn_span, body_span)?;
+ let (span, visible_macro) = unexpand(expn_span)?;
Some(SpanFromMir::new(span, visible_macro, bcb, false))
});
diff --git a/tests/coverage/closure_unit_return.cov-map b/tests/coverage/closure_unit_return.cov-map
index 330a6b420b0e2..c97b4a44dd6b2 100644
--- a/tests/coverage/closure_unit_return.cov-map
+++ b/tests/coverage/closure_unit_return.cov-map
@@ -16,13 +16,13 @@ Number of file 0 mappings: 1
- Code(Zero) at (prev + 8, 22) to (start + 2, 6)
Function name: closure_unit_return::implicit_unit
-Raw bytes (14): 0x[01, 01, 00, 02, 01, 10, 01, 01, 13, 01, 03, 06, 04, 02]
+Raw bytes (14): 0x[01, 01, 00, 02, 01, 10, 01, 01, 10, 01, 05, 05, 02, 02]
Number of files: 1
- file 0 => global file 1
Number of expressions: 0
Number of file 0 mappings: 2
-- Code(Counter(0)) at (prev + 16, 1) to (start + 1, 19)
-- Code(Counter(0)) at (prev + 3, 6) to (start + 4, 2)
+- Code(Counter(0)) at (prev + 16, 1) to (start + 1, 16)
+- Code(Counter(0)) at (prev + 5, 5) to (start + 2, 2)
Function name: closure_unit_return::implicit_unit::{closure#0} (unused)
Raw bytes (9): 0x[01, 01, 00, 01, 00, 11, 16, 02, 06]
diff --git a/tests/coverage/closure_unit_return.coverage b/tests/coverage/closure_unit_return.coverage
index 1a706b3a18d66..1056baa385cb4 100644
--- a/tests/coverage/closure_unit_return.coverage
+++ b/tests/coverage/closure_unit_return.coverage
@@ -16,8 +16,8 @@
LL| 1|fn implicit_unit() {
LL| 1| let closure = || {
LL| 0| ();
- LL| 1| };
- LL| 1|
+ LL| 0| };
+ LL| |
LL| 1| drop(closure);
LL| 1| // implicit return of `()`
LL| 1|}
diff --git a/tests/coverage/coverage_attr_closure.cov-map b/tests/coverage/coverage_attr_closure.cov-map
index 2208b28fd4149..5d2c6b00b40f8 100644
--- a/tests/coverage/coverage_attr_closure.cov-map
+++ b/tests/coverage/coverage_attr_closure.cov-map
@@ -15,14 +15,14 @@ Number of file 0 mappings: 1
- Code(Zero) at (prev + 29, 19) to (start + 2, 6)
Function name: coverage_attr_closure::contains_closures_on
-Raw bytes (19): 0x[01, 01, 00, 03, 01, 0f, 01, 02, 05, 01, 04, 06, 02, 05, 01, 04, 06, 01, 02]
+Raw bytes (19): 0x[01, 01, 00, 03, 01, 0f, 01, 01, 1a, 01, 05, 09, 00, 1b, 01, 04, 01, 00, 02]
Number of files: 1
- file 0 => global file 1
Number of expressions: 0
Number of file 0 mappings: 3
-- Code(Counter(0)) at (prev + 15, 1) to (start + 2, 5)
-- Code(Counter(0)) at (prev + 4, 6) to (start + 2, 5)
-- Code(Counter(0)) at (prev + 4, 6) to (start + 1, 2)
+- Code(Counter(0)) at (prev + 15, 1) to (start + 1, 26)
+- Code(Counter(0)) at (prev + 5, 9) to (start + 0, 27)
+- Code(Counter(0)) at (prev + 4, 1) to (start + 0, 2)
Function name: coverage_attr_closure::contains_closures_on::{closure#0} (unused)
Raw bytes (9): 0x[01, 01, 00, 01, 00, 11, 13, 02, 06]
diff --git a/tests/coverage/coverage_attr_closure.coverage b/tests/coverage/coverage_attr_closure.coverage
index 32c75b40d83c0..3474ad65063ec 100644
--- a/tests/coverage/coverage_attr_closure.coverage
+++ b/tests/coverage/coverage_attr_closure.coverage
@@ -14,13 +14,13 @@
LL| |#[coverage(on)]
LL| 1|fn contains_closures_on() {
LL| 1| let _local_closure_on = #[coverage(on)]
- LL| 1| |input: &str| {
+ LL| 0| |input: &str| {
LL| 0| println!("{input}");
- LL| 1| };
+ LL| 0| };
LL| 1| let _local_closure_off = #[coverage(off)]
- LL| 1| |input: &str| {
+ LL| | |input: &str| {
LL| | println!("{input}");
- LL| 1| };
+ LL| | };
LL| 1|}
LL| |
LL| |#[coverage(off)]
diff --git a/tests/coverage/inline-dead.cov-map b/tests/coverage/inline-dead.cov-map
index c669b7245ead8..f77781ca02839 100644
--- a/tests/coverage/inline-dead.cov-map
+++ b/tests/coverage/inline-dead.cov-map
@@ -22,13 +22,13 @@ Number of file 0 mappings: 4
= (Zero + (c0 - Zero))
Function name: inline_dead::main
-Raw bytes (14): 0x[01, 01, 00, 02, 01, 04, 01, 03, 0d, 01, 05, 06, 02, 02]
+Raw bytes (14): 0x[01, 01, 00, 02, 01, 04, 01, 03, 0a, 01, 06, 05, 01, 02]
Number of files: 1
- file 0 => global file 1
Number of expressions: 0
Number of file 0 mappings: 2
-- Code(Counter(0)) at (prev + 4, 1) to (start + 3, 13)
-- Code(Counter(0)) at (prev + 5, 6) to (start + 2, 2)
+- Code(Counter(0)) at (prev + 4, 1) to (start + 3, 10)
+- Code(Counter(0)) at (prev + 6, 5) to (start + 1, 2)
Function name: inline_dead::main::{closure#0}
Raw bytes (23): 0x[01, 01, 02, 00, 06, 01, 00, 03, 01, 07, 17, 01, 16, 00, 01, 17, 00, 18, 03, 01, 05, 00, 06]
diff --git a/tests/coverage/macro_name_span.cov-map b/tests/coverage/macro_name_span.cov-map
index a18e5f1486147..f3ee44d2a5abc 100644
--- a/tests/coverage/macro_name_span.cov-map
+++ b/tests/coverage/macro_name_span.cov-map
@@ -1,10 +1,10 @@
Function name: macro_name_span::affected_function
-Raw bytes (9): 0x[01, 01, 00, 01, 01, 16, 1c, 02, 06]
+Raw bytes (9): 0x[01, 01, 00, 01, 01, 16, 1c, 01, 40]
Number of files: 1
- file 0 => global file 1
Number of expressions: 0
Number of file 0 mappings: 1
-- Code(Counter(0)) at (prev + 22, 28) to (start + 2, 6)
+- Code(Counter(0)) at (prev + 22, 28) to (start + 1, 64)
Function name: macro_name_span::main
Raw bytes (9): 0x[01, 01, 00, 01, 01, 0b, 01, 02, 02]
diff --git a/tests/coverage/macro_name_span.coverage b/tests/coverage/macro_name_span.coverage
index 28c88b1defa83..0e12ce4a27cad 100644
--- a/tests/coverage/macro_name_span.coverage
+++ b/tests/coverage/macro_name_span.coverage
@@ -21,6 +21,6 @@
LL| |macro_name_span_helper::macro_that_defines_a_function! {
LL| 1| fn affected_function() {
LL| 1| macro_with_an_unreasonably_and_egregiously_long_name!();
- LL| 1| }
+ LL| | }
LL| |}
diff --git a/tests/coverage/unicode.cov-map b/tests/coverage/unicode.cov-map
index cd40194a0831b..aedfb2071c144 100644
--- a/tests/coverage/unicode.cov-map
+++ b/tests/coverage/unicode.cov-map
@@ -27,14 +27,6 @@ Number of file 0 mappings: 9
- Code(Expression(5, Add)) at (prev + 2, 5) to (start + 1, 2)
= (c4 + ((((c0 + c1) - c1) - c2) + c3))
-Function name: unicode::サビ
-Raw bytes (9): 0x[01, 01, 00, 01, 01, 1e, 14, 00, 18]
-Number of files: 1
-- file 0 => global file 1
-Number of expressions: 0
-Number of file 0 mappings: 1
-- Code(Counter(0)) at (prev + 30, 20) to (start + 0, 24)
-
Function name: unicode::他 (unused)
Raw bytes (9): 0x[01, 01, 00, 01, 00, 1e, 19, 00, 25]
Number of files: 1
diff --git a/tests/coverage/unicode.coverage b/tests/coverage/unicode.coverage
index b284a557d5754..af586111ba348 100644
--- a/tests/coverage/unicode.coverage
+++ b/tests/coverage/unicode.coverage
@@ -29,8 +29,7 @@
LL| |
LL| |macro_rules! macro_that_defines_a_function {
LL| | (fn $名:ident () $体:tt) => {
- LL| [0;35m1[0m| fn $名 () $体 [0;41mfn 他 () {}[0m
- ^0
+ LL| 0| fn $名 () $体 [0;41mfn 他 () {}[0m
LL| | }
LL| |}
LL| |