diff --git a/compiler/rustc_mir_build/src/build/coverageinfo.rs b/compiler/rustc_mir_build/src/build/coverageinfo.rs
index 95d72c02682fc..89ca1fb6fa323 100644
--- a/compiler/rustc_mir_build/src/build/coverageinfo.rs
+++ b/compiler/rustc_mir_build/src/build/coverageinfo.rs
@@ -38,6 +38,12 @@ struct NotInfo {
     is_flipped: bool,
 }
 
+pub(crate) struct MatchArm {
+    pub(crate) source_info: SourceInfo,
+    pub(crate) pre_binding_block: Option<BasicBlock>,
+    pub(crate) arm_block: BasicBlock,
+}
+
 impl BranchInfoBuilder {
     /// Creates a new branch info builder, but only if branch coverage instrumentation
     /// is enabled and `def_id` represents a function that is eligible for coverage.
@@ -152,6 +158,31 @@ impl BranchInfoBuilder {
         self.branch_arm_lists.push(vec![arm(true_marker), arm(false_marker)]);
     }
 
+    pub(crate) fn add_match_arms(&mut self, cfg: &mut CFG<'_>, arms: &[MatchArm]) {
+        // Match expressions with 0-1 arms don't have any branches for their arms.
+        if arms.len() < 2 {
+            return;
+        }
+
+        // FIXME(#124118) The current implementation of branch coverage for
+        // match arms can't handle or-patterns.
+        if arms.iter().any(|arm| arm.pre_binding_block.is_none()) {
+            return;
+        }
+
+        let branch_arms = arms
+            .iter()
+            .map(|&MatchArm { source_info, pre_binding_block, arm_block }| {
+                let pre_guard_marker =
+                    self.inject_block_marker(cfg, source_info, pre_binding_block.unwrap());
+                let arm_taken_marker = self.inject_block_marker(cfg, source_info, arm_block);
+                BranchArm { span: source_info.span, pre_guard_marker, arm_taken_marker }
+            })
+            .collect::<Vec<_>>();
+
+        self.branch_arm_lists.push(branch_arms);
+    }
+
     fn next_block_marker_id(&mut self) -> BlockMarkerId {
         let id = BlockMarkerId::from_usize(self.num_block_markers);
         self.num_block_markers += 1;
diff --git a/compiler/rustc_mir_build/src/build/matches/mod.rs b/compiler/rustc_mir_build/src/build/matches/mod.rs
index f46dceeeedf58..a43b6b8f12aa6 100644
--- a/compiler/rustc_mir_build/src/build/matches/mod.rs
+++ b/compiler/rustc_mir_build/src/build/matches/mod.rs
@@ -5,6 +5,7 @@
 //! This also includes code for pattern bindings in `let` statements and
 //! function parameters.
 
+use crate::build::coverageinfo;
 use crate::build::expr::as_place::PlaceBuilder;
 use crate::build::scope::DropKind;
 use crate::build::ForGuard::{self, OutsideGuard, RefWithinGuard};
@@ -461,6 +462,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         outer_source_info: SourceInfo,
         fake_borrow_temps: Vec<(Place<'tcx>, Local)>,
     ) -> BlockAnd<()> {
+        let mut coverage_match_arms = self.coverage_branch_info.is_some().then_some(vec![]);
+
         let arm_end_blocks: Vec<_> = arm_candidates
             .into_iter()
             .map(|(arm, candidate)| {
@@ -495,6 +498,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                         opt_scrutinee_place,
                     );
 
+                    let pre_binding_block = candidate.pre_binding_block;
+
                     let arm_block = this.bind_pattern(
                         outer_source_info,
                         candidate,
@@ -504,6 +509,14 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                         false,
                     );
 
+                    if let Some(coverage_match_arms) = coverage_match_arms.as_mut() {
+                        coverage_match_arms.push(coverageinfo::MatchArm {
+                            source_info: this.source_info(arm.pattern.span),
+                            pre_binding_block,
+                            arm_block,
+                        })
+                    }
+
                     this.fixed_temps_scope = old_dedup_scope;
 
                     if let Some(source_scope) = scope {
@@ -515,6 +528,13 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
             })
             .collect();
 
+        if let Some(coverage_match_arms) = coverage_match_arms {
+            self.coverage_branch_info
+                .as_mut()
+                .expect("checked when creating `coverage_match_arms`")
+                .add_match_arms(&mut self.cfg, &coverage_match_arms);
+        }
+
         // all the arm blocks will rejoin here
         let end_block = self.cfg.start_new_block();
 
diff --git a/tests/coverage/branch/guard-simple.cov-map b/tests/coverage/branch/guard-simple.cov-map
index 8eb9c54ff4bca..50654ae661afb 100644
--- a/tests/coverage/branch/guard-simple.cov-map
+++ b/tests/coverage/branch/guard-simple.cov-map
@@ -1,24 +1,35 @@
 Function name: guard_simple::never_taken
-Raw bytes (56): 0x[01, 01, 04, 01, 05, 11, 09, 0f, 0d, 05, 09, 08, 01, 08, 01, 02, 1e, 20, 05, 02, 02, 0e, 00, 1e, 05, 00, 22, 00, 24, 11, 01, 0e, 00, 1e, 20, 09, 06, 00, 0e, 00, 1e, 09, 00, 22, 00, 24, 0d, 01, 0e, 00, 10, 0b, 02, 01, 00, 02]
+Raw bytes (80): 0x[01, 01, 09, 07, 01, 17, 05, 0d, 09, 01, 05, 17, 11, 0d, 09, 11, 09, 23, 0d, 05, 09, 0a, 01, 08, 01, 02, 1e, 20, 01, 02, 02, 09, 00, 0a, 20, 05, 0e, 00, 0e, 00, 1e, 05, 00, 22, 00, 24, 20, 11, 12, 01, 09, 00, 0a, 11, 00, 0e, 00, 1e, 20, 09, 1a, 00, 0e, 00, 1e, 09, 00, 22, 00, 24, 0d, 01, 0e, 00, 10, 1f, 02, 01, 00, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 4
-- expression 0 operands: lhs = Counter(0), rhs = Counter(1)
-- expression 1 operands: lhs = Counter(4), rhs = Counter(2)
-- expression 2 operands: lhs = Expression(3, Add), rhs = Counter(3)
-- expression 3 operands: lhs = Counter(1), rhs = Counter(2)
-Number of file 0 mappings: 8
+Number of expressions: 9
+- expression 0 operands: lhs = Expression(1, Add), rhs = Counter(0)
+- expression 1 operands: lhs = Expression(5, Add), rhs = Counter(1)
+- expression 2 operands: lhs = Counter(3), rhs = Counter(2)
+- expression 3 operands: lhs = Counter(0), rhs = Counter(1)
+- expression 4 operands: lhs = Expression(5, Add), rhs = Counter(4)
+- expression 5 operands: lhs = Counter(3), rhs = Counter(2)
+- expression 6 operands: lhs = Counter(4), rhs = Counter(2)
+- expression 7 operands: lhs = Expression(8, Add), rhs = Counter(3)
+- expression 8 operands: lhs = Counter(1), rhs = Counter(2)
+Number of file 0 mappings: 10
 - Code(Counter(0)) at (prev + 8, 1) to (start + 2, 30)
-- Branch { true: Counter(1), false: Expression(0, Sub) } at (prev + 2, 14) to (start + 0, 30)
+- Branch { true: Counter(0), false: Expression(0, Sub) } at (prev + 2, 9) to (start + 0, 10)
+    true  = c0
+    false = (((c3 + c2) + c1) - c0)
+- Branch { true: Counter(1), false: Expression(3, Sub) } at (prev + 0, 14) to (start + 0, 30)
     true  = c1
     false = (c0 - c1)
 - Code(Counter(1)) at (prev + 0, 34) to (start + 0, 36)
-- Code(Counter(4)) at (prev + 1, 14) to (start + 0, 30)
-- Branch { true: Counter(2), false: Expression(1, Sub) } at (prev + 0, 14) to (start + 0, 30)
+- Branch { true: Counter(4), false: Expression(4, Sub) } at (prev + 1, 9) to (start + 0, 10)
+    true  = c4
+    false = ((c3 + c2) - c4)
+- Code(Counter(4)) at (prev + 0, 14) to (start + 0, 30)
+- Branch { true: Counter(2), false: Expression(6, Sub) } at (prev + 0, 14) to (start + 0, 30)
     true  = c2
     false = (c4 - c2)
 - Code(Counter(2)) at (prev + 0, 34) to (start + 0, 36)
 - Code(Counter(3)) at (prev + 1, 14) to (start + 0, 16)
-- Code(Expression(2, Add)) at (prev + 2, 1) to (start + 0, 2)
+- Code(Expression(7, Add)) at (prev + 2, 1) to (start + 0, 2)
     = ((c1 + c2) + c3)
 
diff --git a/tests/coverage/branch/guard-simple.coverage b/tests/coverage/branch/guard-simple.coverage
index ac90c48c44342..06ad332a927da 100644
--- a/tests/coverage/branch/guard-simple.coverage
+++ b/tests/coverage/branch/guard-simple.coverage
@@ -10,11 +10,13 @@
    LL|      1|        _ if black_box(false) => {}
                                                ^0
   ------------------
+  |  Branch (LL:9): [True: 1, False: 0]
   |  Branch (LL:14): [True: 0, False: 1]
   ------------------
    LL|      1|        _ if black_box(false) => {}
                                                ^0
   ------------------
+  |  Branch (LL:9): [True: 1, False: 0]
   |  Branch (LL:14): [True: 0, False: 1]
   ------------------
    LL|      1|        _ => {}
diff --git a/tests/coverage/branch/guard.cov-map b/tests/coverage/branch/guard.cov-map
index d67c3d349a14e..18dd0c302cbfa 100644
--- a/tests/coverage/branch/guard.cov-map
+++ b/tests/coverage/branch/guard.cov-map
@@ -1,32 +1,48 @@
 Function name: guard::branch_match_guard
-Raw bytes (85): 0x[01, 01, 06, 19, 0d, 05, 09, 0f, 15, 13, 11, 17, 0d, 05, 09, 0d, 01, 0c, 01, 01, 10, 1d, 03, 0b, 00, 0c, 15, 01, 14, 02, 0a, 0d, 03, 0e, 00, 0f, 19, 00, 14, 00, 19, 20, 0d, 02, 00, 14, 00, 1e, 0d, 00, 1d, 02, 0a, 11, 03, 0e, 00, 0f, 1d, 00, 14, 00, 19, 20, 11, 09, 00, 14, 00, 1e, 11, 00, 1d, 02, 0a, 17, 03, 0e, 02, 0a, 0b, 04, 01, 00, 02]
+Raw bytes (120): 0x[01, 01, 0d, 1b, 0d, 33, 11, 05, 09, 03, 19, 19, 0d, 1b, 1d, 33, 11, 05, 09, 05, 09, 2b, 15, 2f, 11, 33, 0d, 05, 09, 10, 01, 0c, 01, 01, 10, 1d, 03, 0b, 00, 0c, 20, 15, 03, 01, 09, 00, 10, 15, 00, 14, 02, 0a, 20, 19, 0e, 03, 09, 00, 10, 0d, 00, 0e, 00, 0f, 19, 00, 14, 00, 19, 20, 0d, 12, 00, 14, 00, 1e, 0d, 00, 1d, 02, 0a, 20, 1d, 16, 03, 09, 00, 10, 11, 00, 0e, 00, 0f, 1d, 00, 14, 00, 19, 20, 11, 09, 00, 14, 00, 1e, 11, 00, 1d, 02, 0a, 33, 03, 0e, 02, 0a, 27, 04, 01, 00, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 6
-- expression 0 operands: lhs = Counter(6), rhs = Counter(3)
-- expression 1 operands: lhs = Counter(1), rhs = Counter(2)
-- expression 2 operands: lhs = Expression(3, Add), rhs = Counter(5)
-- expression 3 operands: lhs = Expression(4, Add), rhs = Counter(4)
-- expression 4 operands: lhs = Expression(5, Add), rhs = Counter(3)
-- expression 5 operands: lhs = Counter(1), rhs = Counter(2)
-Number of file 0 mappings: 13
+Number of expressions: 13
+- expression 0 operands: lhs = Expression(6, Add), rhs = Counter(3)
+- expression 1 operands: lhs = Expression(12, Add), rhs = Counter(4)
+- expression 2 operands: lhs = Counter(1), rhs = Counter(2)
+- expression 3 operands: lhs = Expression(0, Add), rhs = Counter(6)
+- expression 4 operands: lhs = Counter(6), rhs = Counter(3)
+- expression 5 operands: lhs = Expression(6, Add), rhs = Counter(7)
+- expression 6 operands: lhs = Expression(12, Add), rhs = Counter(4)
+- expression 7 operands: lhs = Counter(1), rhs = Counter(2)
+- expression 8 operands: lhs = Counter(1), rhs = Counter(2)
+- expression 9 operands: lhs = Expression(10, Add), rhs = Counter(5)
+- expression 10 operands: lhs = Expression(11, Add), rhs = Counter(4)
+- expression 11 operands: lhs = Expression(12, Add), rhs = Counter(3)
+- expression 12 operands: lhs = Counter(1), rhs = Counter(2)
+Number of file 0 mappings: 16
 - Code(Counter(0)) at (prev + 12, 1) to (start + 1, 16)
 - Code(Counter(7)) at (prev + 3, 11) to (start + 0, 12)
-- Code(Counter(5)) at (prev + 1, 20) to (start + 2, 10)
-- Code(Counter(3)) at (prev + 3, 14) to (start + 0, 15)
+- Branch { true: Counter(5), false: Expression(0, Add) } at (prev + 1, 9) to (start + 0, 16)
+    true  = c5
+    false = (((c1 + c2) + c4) + c3)
+- Code(Counter(5)) at (prev + 0, 20) to (start + 2, 10)
+- Branch { true: Counter(6), false: Expression(3, Sub) } at (prev + 3, 9) to (start + 0, 16)
+    true  = c6
+    false = ((((c1 + c2) + c4) + c3) - c6)
+- Code(Counter(3)) at (prev + 0, 14) to (start + 0, 15)
 - Code(Counter(6)) at (prev + 0, 20) to (start + 0, 25)
-- Branch { true: Counter(3), false: Expression(0, Sub) } at (prev + 0, 20) to (start + 0, 30)
+- Branch { true: Counter(3), false: Expression(4, Sub) } at (prev + 0, 20) to (start + 0, 30)
     true  = c3
     false = (c6 - c3)
 - Code(Counter(3)) at (prev + 0, 29) to (start + 2, 10)
-- Code(Counter(4)) at (prev + 3, 14) to (start + 0, 15)
+- Branch { true: Counter(7), false: Expression(5, Sub) } at (prev + 3, 9) to (start + 0, 16)
+    true  = c7
+    false = (((c1 + c2) + c4) - c7)
+- Code(Counter(4)) at (prev + 0, 14) to (start + 0, 15)
 - Code(Counter(7)) at (prev + 0, 20) to (start + 0, 25)
 - Branch { true: Counter(4), false: Counter(2) } at (prev + 0, 20) to (start + 0, 30)
     true  = c4
     false = c2
 - Code(Counter(4)) at (prev + 0, 29) to (start + 2, 10)
-- Code(Expression(5, Add)) at (prev + 3, 14) to (start + 2, 10)
+- Code(Expression(12, Add)) at (prev + 3, 14) to (start + 2, 10)
     = (c1 + c2)
-- Code(Expression(2, Add)) at (prev + 4, 1) to (start + 0, 2)
+- Code(Expression(9, Add)) at (prev + 4, 1) to (start + 0, 2)
     = ((((c1 + c2) + c3) + c4) + c5)
 
diff --git a/tests/coverage/branch/guard.coverage b/tests/coverage/branch/guard.coverage
index f89b965b5d0f7..6b1b650d4703c 100644
--- a/tests/coverage/branch/guard.coverage
+++ b/tests/coverage/branch/guard.coverage
@@ -14,17 +14,22 @@
    LL|       |
    LL|      1|    match x {
    LL|      1|        Some(0) => {
+  ------------------
+  |  Branch (LL:9): [True: 1, False: 3]
+  ------------------
    LL|      1|            println!("zero");
    LL|      1|        }
    LL|      3|        Some(x) if x % 2 == 0 => {
                            ^2
   ------------------
+  |  Branch (LL:9): [True: 3, False: 0]
   |  Branch (LL:20): [True: 2, False: 1]
   ------------------
    LL|      2|            println!("is nonzero and even");
    LL|      2|        }
    LL|      1|        Some(x) if x % 3 == 0 => {
   ------------------
+  |  Branch (LL:9): [True: 1, False: 0]
   |  Branch (LL:20): [True: 1, False: 0]
   ------------------
    LL|      1|            println!("is nonzero and odd, but divisible by 3");
diff --git a/tests/coverage/branch/match-arms.cov-map b/tests/coverage/branch/match-arms.cov-map
index 1f17f11baaa07..04c39db4c5c31 100644
--- a/tests/coverage/branch/match-arms.cov-map
+++ b/tests/coverage/branch/match-arms.cov-map
@@ -1,60 +1,130 @@
 Function name: match_arms::guards
-Raw bytes (88): 0x[01, 01, 08, 07, 15, 0b, 11, 0f, 0d, 00, 09, 17, 25, 1b, 21, 1f, 1d, 03, 19, 0c, 01, 30, 01, 01, 10, 29, 03, 0b, 00, 10, 19, 01, 11, 00, 29, 20, 19, 09, 00, 17, 00, 1b, 1d, 01, 11, 00, 29, 20, 1d, 0d, 00, 17, 00, 1b, 21, 01, 11, 00, 29, 20, 21, 11, 00, 17, 00, 1b, 25, 01, 11, 00, 29, 20, 25, 15, 00, 17, 00, 1b, 03, 01, 0e, 00, 18, 13, 03, 05, 01, 02]
+Raw bytes (212): 0x[01, 01, 2a, 07, 35, 2b, 19, 4b, 1d, 67, 21, 9b, 01, 25, 9f, 01, 15, a3, 01, 11, a7, 01, 0d, 00, 09, 2b, 31, 4b, 1d, 67, 21, 9b, 01, 25, 9f, 01, 15, a3, 01, 11, a7, 01, 0d, 00, 09, 4b, 2d, 67, 21, 9b, 01, 25, 9f, 01, 15, a3, 01, 11, a7, 01, 0d, 00, 09, 67, 29, 9b, 01, 25, 9f, 01, 15, a3, 01, 11, a7, 01, 0d, 00, 09, 9f, 01, 15, a3, 01, 11, a7, 01, 0d, 00, 09, 8f, 01, 25, 93, 01, 21, 97, 01, 1d, 9b, 01, 19, 9f, 01, 15, a3, 01, 11, a7, 01, 0d, 00, 09, 10, 01, 30, 01, 01, 10, 29, 03, 0b, 00, 10, 20, 35, 02, 01, 09, 00, 13, 19, 00, 11, 00, 29, 20, 19, 09, 00, 17, 00, 1b, 20, 31, 26, 01, 09, 00, 13, 1d, 00, 11, 00, 29, 20, 1d, 0d, 00, 17, 00, 1b, 20, 2d, 46, 01, 09, 00, 13, 21, 00, 11, 00, 29, 20, 21, 11, 00, 17, 00, 1b, 20, 29, 62, 01, 09, 00, 13, 25, 00, 11, 00, 29, 20, 25, 15, 00, 17, 00, 1b, 9b, 01, 01, 0e, 00, 18, 8b, 01, 03, 05, 01, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 8
-- expression 0 operands: lhs = Expression(1, Add), rhs = Counter(5)
-- expression 1 operands: lhs = Expression(2, Add), rhs = Counter(4)
-- expression 2 operands: lhs = Expression(3, Add), rhs = Counter(3)
-- expression 3 operands: lhs = Zero, rhs = Counter(2)
-- expression 4 operands: lhs = Expression(5, Add), rhs = Counter(9)
-- expression 5 operands: lhs = Expression(6, Add), rhs = Counter(8)
-- expression 6 operands: lhs = Expression(7, Add), rhs = Counter(7)
-- expression 7 operands: lhs = Expression(0, Add), rhs = Counter(6)
-Number of file 0 mappings: 12
+Number of expressions: 42
+- expression 0 operands: lhs = Expression(1, Add), rhs = Counter(13)
+- expression 1 operands: lhs = Expression(10, Add), rhs = Counter(6)
+- expression 2 operands: lhs = Expression(18, Add), rhs = Counter(7)
+- expression 3 operands: lhs = Expression(25, Add), rhs = Counter(8)
+- expression 4 operands: lhs = Expression(38, Add), rhs = Counter(9)
+- expression 5 operands: lhs = Expression(39, Add), rhs = Counter(5)
+- expression 6 operands: lhs = Expression(40, Add), rhs = Counter(4)
+- expression 7 operands: lhs = Expression(41, Add), rhs = Counter(3)
+- expression 8 operands: lhs = Zero, rhs = Counter(2)
+- expression 9 operands: lhs = Expression(10, Add), rhs = Counter(12)
+- expression 10 operands: lhs = Expression(18, Add), rhs = Counter(7)
+- expression 11 operands: lhs = Expression(25, Add), rhs = Counter(8)
+- expression 12 operands: lhs = Expression(38, Add), rhs = Counter(9)
+- expression 13 operands: lhs = Expression(39, Add), rhs = Counter(5)
+- expression 14 operands: lhs = Expression(40, Add), rhs = Counter(4)
+- expression 15 operands: lhs = Expression(41, Add), rhs = Counter(3)
+- expression 16 operands: lhs = Zero, rhs = Counter(2)
+- expression 17 operands: lhs = Expression(18, Add), rhs = Counter(11)
+- expression 18 operands: lhs = Expression(25, Add), rhs = Counter(8)
+- expression 19 operands: lhs = Expression(38, Add), rhs = Counter(9)
+- expression 20 operands: lhs = Expression(39, Add), rhs = Counter(5)
+- expression 21 operands: lhs = Expression(40, Add), rhs = Counter(4)
+- expression 22 operands: lhs = Expression(41, Add), rhs = Counter(3)
+- expression 23 operands: lhs = Zero, rhs = Counter(2)
+- expression 24 operands: lhs = Expression(25, Add), rhs = Counter(10)
+- expression 25 operands: lhs = Expression(38, Add), rhs = Counter(9)
+- expression 26 operands: lhs = Expression(39, Add), rhs = Counter(5)
+- expression 27 operands: lhs = Expression(40, Add), rhs = Counter(4)
+- expression 28 operands: lhs = Expression(41, Add), rhs = Counter(3)
+- expression 29 operands: lhs = Zero, rhs = Counter(2)
+- expression 30 operands: lhs = Expression(39, Add), rhs = Counter(5)
+- expression 31 operands: lhs = Expression(40, Add), rhs = Counter(4)
+- expression 32 operands: lhs = Expression(41, Add), rhs = Counter(3)
+- expression 33 operands: lhs = Zero, rhs = Counter(2)
+- expression 34 operands: lhs = Expression(35, Add), rhs = Counter(9)
+- expression 35 operands: lhs = Expression(36, Add), rhs = Counter(8)
+- expression 36 operands: lhs = Expression(37, Add), rhs = Counter(7)
+- expression 37 operands: lhs = Expression(38, Add), rhs = Counter(6)
+- expression 38 operands: lhs = Expression(39, Add), rhs = Counter(5)
+- expression 39 operands: lhs = Expression(40, Add), rhs = Counter(4)
+- expression 40 operands: lhs = Expression(41, Add), rhs = Counter(3)
+- expression 41 operands: lhs = Zero, rhs = Counter(2)
+Number of file 0 mappings: 16
 - Code(Counter(0)) at (prev + 48, 1) to (start + 1, 16)
 - Code(Counter(10)) at (prev + 3, 11) to (start + 0, 16)
-- Code(Counter(6)) at (prev + 1, 17) to (start + 0, 41)
+- Branch { true: Counter(13), false: Expression(0, Sub) } at (prev + 1, 9) to (start + 0, 19)
+    true  = c13
+    false = (((((((((Zero + c2) + c3) + c4) + c5) + c9) + c8) + c7) + c6) - c13)
+- Code(Counter(6)) at (prev + 0, 17) to (start + 0, 41)
 - Branch { true: Counter(6), false: Counter(2) } at (prev + 0, 23) to (start + 0, 27)
     true  = c6
     false = c2
-- Code(Counter(7)) at (prev + 1, 17) to (start + 0, 41)
+- Branch { true: Counter(12), false: Expression(9, Sub) } at (prev + 1, 9) to (start + 0, 19)
+    true  = c12
+    false = ((((((((Zero + c2) + c3) + c4) + c5) + c9) + c8) + c7) - c12)
+- Code(Counter(7)) at (prev + 0, 17) to (start + 0, 41)
 - Branch { true: Counter(7), false: Counter(3) } at (prev + 0, 23) to (start + 0, 27)
     true  = c7
     false = c3
-- Code(Counter(8)) at (prev + 1, 17) to (start + 0, 41)
+- Branch { true: Counter(11), false: Expression(17, Sub) } at (prev + 1, 9) to (start + 0, 19)
+    true  = c11
+    false = (((((((Zero + c2) + c3) + c4) + c5) + c9) + c8) - c11)
+- Code(Counter(8)) at (prev + 0, 17) to (start + 0, 41)
 - Branch { true: Counter(8), false: Counter(4) } at (prev + 0, 23) to (start + 0, 27)
     true  = c8
     false = c4
-- Code(Counter(9)) at (prev + 1, 17) to (start + 0, 41)
+- Branch { true: Counter(10), false: Expression(24, Sub) } at (prev + 1, 9) to (start + 0, 19)
+    true  = c10
+    false = ((((((Zero + c2) + c3) + c4) + c5) + c9) - c10)
+- Code(Counter(9)) at (prev + 0, 17) to (start + 0, 41)
 - Branch { true: Counter(9), false: Counter(5) } at (prev + 0, 23) to (start + 0, 27)
     true  = c9
     false = c5
-- Code(Expression(0, Add)) at (prev + 1, 14) to (start + 0, 24)
+- Code(Expression(38, Add)) at (prev + 1, 14) to (start + 0, 24)
     = ((((Zero + c2) + c3) + c4) + c5)
-- Code(Expression(4, Add)) at (prev + 3, 5) to (start + 1, 2)
+- Code(Expression(34, Add)) at (prev + 3, 5) to (start + 1, 2)
     = ((((((((Zero + c2) + c3) + c4) + c5) + c6) + c7) + c8) + c9)
 
 Function name: match_arms::match_arms
-Raw bytes (51): 0x[01, 01, 06, 05, 07, 0b, 11, 09, 0d, 13, 02, 17, 09, 11, 0d, 07, 01, 18, 01, 01, 10, 05, 03, 0b, 00, 10, 11, 01, 11, 00, 21, 0d, 01, 11, 00, 21, 09, 01, 11, 00, 21, 02, 01, 11, 00, 21, 0f, 03, 05, 01, 02]
+Raw bytes (102): 0x[01, 01, 15, 17, 0d, 4a, 09, 05, 4f, 53, 11, 09, 0d, 4a, 09, 05, 4f, 53, 11, 09, 0d, 05, 4f, 53, 11, 09, 0d, 05, 4f, 53, 11, 09, 0d, 43, 4a, 47, 09, 11, 0d, 05, 4f, 53, 11, 09, 0d, 0a, 01, 18, 01, 01, 10, 05, 03, 0b, 00, 10, 20, 11, 03, 01, 09, 00, 13, 11, 00, 11, 00, 21, 20, 0d, 17, 01, 09, 00, 13, 0d, 00, 11, 00, 21, 20, 09, 4a, 01, 09, 00, 13, 09, 00, 11, 00, 21, 4a, 01, 11, 00, 21, 3f, 03, 05, 01, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 6
-- expression 0 operands: lhs = Counter(1), rhs = Expression(1, Add)
-- expression 1 operands: lhs = Expression(2, Add), rhs = Counter(4)
-- expression 2 operands: lhs = Counter(2), rhs = Counter(3)
-- expression 3 operands: lhs = Expression(4, Add), rhs = Expression(0, Sub)
-- expression 4 operands: lhs = Expression(5, Add), rhs = Counter(2)
-- expression 5 operands: lhs = Counter(4), rhs = Counter(3)
-Number of file 0 mappings: 7
+Number of expressions: 21
+- expression 0 operands: lhs = Expression(5, Add), rhs = Counter(3)
+- expression 1 operands: lhs = Expression(18, Sub), rhs = Counter(2)
+- expression 2 operands: lhs = Counter(1), rhs = Expression(19, Add)
+- expression 3 operands: lhs = Expression(20, Add), rhs = Counter(4)
+- expression 4 operands: lhs = Counter(2), rhs = Counter(3)
+- expression 5 operands: lhs = Expression(18, Sub), rhs = Counter(2)
+- expression 6 operands: lhs = Counter(1), rhs = Expression(19, Add)
+- expression 7 operands: lhs = Expression(20, Add), rhs = Counter(4)
+- expression 8 operands: lhs = Counter(2), rhs = Counter(3)
+- expression 9 operands: lhs = Counter(1), rhs = Expression(19, Add)
+- expression 10 operands: lhs = Expression(20, Add), rhs = Counter(4)
+- expression 11 operands: lhs = Counter(2), rhs = Counter(3)
+- expression 12 operands: lhs = Counter(1), rhs = Expression(19, Add)
+- expression 13 operands: lhs = Expression(20, Add), rhs = Counter(4)
+- expression 14 operands: lhs = Counter(2), rhs = Counter(3)
+- expression 15 operands: lhs = Expression(16, Add), rhs = Expression(18, Sub)
+- expression 16 operands: lhs = Expression(17, Add), rhs = Counter(2)
+- expression 17 operands: lhs = Counter(4), rhs = Counter(3)
+- expression 18 operands: lhs = Counter(1), rhs = Expression(19, Add)
+- expression 19 operands: lhs = Expression(20, Add), rhs = Counter(4)
+- expression 20 operands: lhs = Counter(2), rhs = Counter(3)
+Number of file 0 mappings: 10
 - Code(Counter(0)) at (prev + 24, 1) to (start + 1, 16)
 - Code(Counter(1)) at (prev + 3, 11) to (start + 0, 16)
-- Code(Counter(4)) at (prev + 1, 17) to (start + 0, 33)
-- Code(Counter(3)) at (prev + 1, 17) to (start + 0, 33)
-- Code(Counter(2)) at (prev + 1, 17) to (start + 0, 33)
-- Code(Expression(0, Sub)) at (prev + 1, 17) to (start + 0, 33)
+- Branch { true: Counter(4), false: Expression(0, Add) } at (prev + 1, 9) to (start + 0, 19)
+    true  = c4
+    false = (((c1 - ((c2 + c3) + c4)) + c2) + c3)
+- Code(Counter(4)) at (prev + 0, 17) to (start + 0, 33)
+- Branch { true: Counter(3), false: Expression(5, Add) } at (prev + 1, 9) to (start + 0, 19)
+    true  = c3
+    false = ((c1 - ((c2 + c3) + c4)) + c2)
+- Code(Counter(3)) at (prev + 0, 17) to (start + 0, 33)
+- Branch { true: Counter(2), false: Expression(18, Sub) } at (prev + 1, 9) to (start + 0, 19)
+    true  = c2
+    false = (c1 - ((c2 + c3) + c4))
+- Code(Counter(2)) at (prev + 0, 17) to (start + 0, 33)
+- Code(Expression(18, Sub)) at (prev + 1, 17) to (start + 0, 33)
     = (c1 - ((c2 + c3) + c4))
-- Code(Expression(3, Add)) at (prev + 3, 5) to (start + 1, 2)
+- Code(Expression(15, Add)) at (prev + 3, 5) to (start + 1, 2)
     = (((c4 + c3) + c2) + (c1 - ((c2 + c3) + c4)))
 
 Function name: match_arms::or_patterns
diff --git a/tests/coverage/branch/match-arms.coverage b/tests/coverage/branch/match-arms.coverage
index ea8a6f97ab154..23d0fadb3b24c 100644
--- a/tests/coverage/branch/match-arms.coverage
+++ b/tests/coverage/branch/match-arms.coverage
@@ -26,8 +26,17 @@
    LL|       |
    LL|     15|    match value {
    LL|      8|        Enum::D(d) => consume(d),
+  ------------------
+  |  Branch (LL:9): [True: 8, False: 7]
+  ------------------
    LL|      4|        Enum::C(c) => consume(c),
+  ------------------
+  |  Branch (LL:9): [True: 4, False: 3]
+  ------------------
    LL|      2|        Enum::B(b) => consume(b),
+  ------------------
+  |  Branch (LL:9): [True: 2, False: 1]
+  ------------------
    LL|      1|        Enum::A(a) => consume(a),
    LL|       |    }
    LL|       |
@@ -53,18 +62,22 @@
    LL|      3|    match value {
    LL|      8|        Enum::D(d) if cond => consume(d),
   ------------------
+  |  Branch (LL:9): [True: 24, False: 21]
   |  Branch (LL:23): [True: 8, False: 16]
   ------------------
    LL|      4|        Enum::C(c) if cond => consume(c),
   ------------------
+  |  Branch (LL:9): [True: 12, False: 25]
   |  Branch (LL:23): [True: 4, False: 8]
   ------------------
    LL|      2|        Enum::B(b) if cond => consume(b),
   ------------------
+  |  Branch (LL:9): [True: 6, False: 27]
   |  Branch (LL:23): [True: 2, False: 4]
   ------------------
    LL|      1|        Enum::A(a) if cond => consume(a),
   ------------------
+  |  Branch (LL:9): [True: 3, False: 28]
   |  Branch (LL:23): [True: 1, False: 2]
   ------------------
    LL|     30|        _ => consume(0),
@@ -101,5 +114,5 @@
    LL|       |    }
    LL|       |}
    LL|       |
-   LL|       |// FIXME(#124118) Actually instrument match arms for branch coverage.
+   LL|       |// FIXME(#124118) Support match expressions with guards or or-patterns.
 
diff --git a/tests/coverage/branch/match-arms.rs b/tests/coverage/branch/match-arms.rs
index 63151f59ffe9b..8b4d3ae87a25f 100644
--- a/tests/coverage/branch/match-arms.rs
+++ b/tests/coverage/branch/match-arms.rs
@@ -87,4 +87,4 @@ fn main() {
     }
 }
 
-// FIXME(#124118) Actually instrument match arms for branch coverage.
+// FIXME(#124118) Support match expressions with guards or or-patterns.
diff --git a/tests/mir-opt/coverage/branch_match_arms.main.InstrumentCoverage.diff b/tests/mir-opt/coverage/branch_match_arms.main.InstrumentCoverage.diff
index e60f71f47b1ed..12d993298bb5a 100644
--- a/tests/mir-opt/coverage/branch_match_arms.main.InstrumentCoverage.diff
+++ b/tests/mir-opt/coverage/branch_match_arms.main.InstrumentCoverage.diff
@@ -26,18 +26,31 @@
           debug a => _9;
       }
   
+      coverage branches {
+          BlockMarkerId(0), BlockMarkerId(1) => $DIR/branch_match_arms.rs:16:9: 16:19 (#0)
+          BlockMarkerId(2), BlockMarkerId(3) => $DIR/branch_match_arms.rs:17:9: 17:19 (#0)
+          BlockMarkerId(4), BlockMarkerId(5) => $DIR/branch_match_arms.rs:18:9: 18:19 (#0)
+          BlockMarkerId(6), BlockMarkerId(7) => $DIR/branch_match_arms.rs:19:9: 19:19 (#0)
+      }
+  
 +     coverage ExpressionId(0) => Expression { lhs: Counter(1), op: Add, rhs: Counter(2) };
 +     coverage ExpressionId(1) => Expression { lhs: Expression(0), op: Add, rhs: Counter(3) };
 +     coverage ExpressionId(2) => Expression { lhs: Counter(0), op: Subtract, rhs: Expression(1) };
 +     coverage ExpressionId(3) => Expression { lhs: Counter(3), op: Add, rhs: Counter(2) };
 +     coverage ExpressionId(4) => Expression { lhs: Expression(3), op: Add, rhs: Counter(1) };
 +     coverage ExpressionId(5) => Expression { lhs: Expression(4), op: Add, rhs: Expression(2) };
++     coverage ExpressionId(6) => Expression { lhs: Expression(2), op: Add, rhs: Counter(1) };
++     coverage ExpressionId(7) => Expression { lhs: Expression(6), op: Add, rhs: Counter(2) };
++     coverage ExpressionId(8) => Expression { lhs: Expression(7), op: Add, rhs: Counter(3) };
 +     coverage Code(Counter(0)) => $DIR/branch_match_arms.rs:14:1 - 15:21;
 +     coverage Code(Counter(3)) => $DIR/branch_match_arms.rs:16:17 - 16:33;
 +     coverage Code(Counter(2)) => $DIR/branch_match_arms.rs:17:17 - 17:33;
 +     coverage Code(Counter(1)) => $DIR/branch_match_arms.rs:18:17 - 18:33;
 +     coverage Code(Expression(2)) => $DIR/branch_match_arms.rs:19:17 - 19:33;
 +     coverage Code(Expression(5)) => $DIR/branch_match_arms.rs:21:1 - 21:2;
++     coverage Branch { true_term: Counter(1), false_term: Expression(2) } => $DIR/branch_match_arms.rs:18:9 - 18:19;
++     coverage Branch { true_term: Counter(2), false_term: Expression(6) } => $DIR/branch_match_arms.rs:17:9 - 17:19;
++     coverage Branch { true_term: Counter(3), false_term: Expression(7) } => $DIR/branch_match_arms.rs:16:9 - 16:19;
 + 
       bb0: {
 +         Coverage::CounterIncrement(0);
@@ -55,16 +68,19 @@
   
       bb2: {
 +         Coverage::CounterIncrement(3);
+          Coverage::BlockMarker(0);
           falseEdge -> [real: bb6, imaginary: bb3];
       }
   
       bb3: {
 +         Coverage::CounterIncrement(2);
+          Coverage::BlockMarker(2);
           falseEdge -> [real: bb8, imaginary: bb4];
       }
   
       bb4: {
 +         Coverage::CounterIncrement(1);
+          Coverage::BlockMarker(4);
           falseEdge -> [real: bb10, imaginary: bb5];
       }
   
@@ -74,6 +90,8 @@
           _9 = ((_1 as A).0: u32);
           StorageLive(_10);
           _10 = _9;
+          Coverage::BlockMarker(6);
+          Coverage::BlockMarker(7);
           _0 = consume(move _10) -> [return: bb12, unwind: bb14];
       }
   
@@ -82,6 +100,7 @@
           _3 = ((_1 as D).0: u32);
           StorageLive(_4);
           _4 = _3;
+          Coverage::BlockMarker(1);
           _0 = consume(move _4) -> [return: bb7, unwind: bb14];
       }
   
@@ -96,6 +115,7 @@
           _5 = ((_1 as C).0: u32);
           StorageLive(_6);
           _6 = _5;
+          Coverage::BlockMarker(3);
           _0 = consume(move _6) -> [return: bb9, unwind: bb14];
       }
   
@@ -110,6 +130,7 @@
           _7 = ((_1 as B).0: u32);
           StorageLive(_8);
           _8 = _7;
+          Coverage::BlockMarker(5);
           _0 = consume(move _8) -> [return: bb11, unwind: bb14];
       }
   
diff --git a/tests/mir-opt/coverage/instrument_coverage_cleanup.main.CleanupPostBorrowck.diff b/tests/mir-opt/coverage/instrument_coverage_cleanup.main.CleanupPostBorrowck.diff
index 8802f7134b3cc..e2d8f6140c609 100644
--- a/tests/mir-opt/coverage/instrument_coverage_cleanup.main.CleanupPostBorrowck.diff
+++ b/tests/mir-opt/coverage/instrument_coverage_cleanup.main.CleanupPostBorrowck.diff
@@ -6,13 +6,13 @@
       let mut _1: bool;
   
       coverage branches {
-          BlockMarkerId(0) => $DIR/instrument_coverage_cleanup.rs:14:8: 14:36 (#0)
-          BlockMarkerId(1) => $DIR/instrument_coverage_cleanup.rs:14:8: 14:36 (#0)
+          BlockMarkerId(0), BlockMarkerId(0) => $DIR/instrument_coverage_cleanup.rs:14:8: 14:36 (#0)
+          BlockMarkerId(1), BlockMarkerId(1) => $DIR/instrument_coverage_cleanup.rs:14:8: 14:36 (#0)
       }
   
       coverage ExpressionId(0) => Expression { lhs: Counter(0), op: Subtract, rhs: Counter(1) };
       coverage ExpressionId(1) => Expression { lhs: Counter(1), op: Add, rhs: Expression(0) };
-      coverage ExpressionId(2) => Expression { lhs: Expression(0), op: Add, rhs: Counter(1) };
+      coverage ExpressionId(2) => Expression { lhs: Counter(1), op: Add, rhs: Expression(0) };
       coverage Code(Counter(0)) => $DIR/instrument_coverage_cleanup.rs:13:1 - 14:36;
       coverage Code(Expression(0)) => $DIR/instrument_coverage_cleanup.rs:14:37 - 14:39;
       coverage Code(Counter(1)) => $DIR/instrument_coverage_cleanup.rs:14:39 - 14:40;
diff --git a/tests/mir-opt/coverage/instrument_coverage_cleanup.main.InstrumentCoverage.diff b/tests/mir-opt/coverage/instrument_coverage_cleanup.main.InstrumentCoverage.diff
index 4739d91de11a1..cf346380249ca 100644
--- a/tests/mir-opt/coverage/instrument_coverage_cleanup.main.InstrumentCoverage.diff
+++ b/tests/mir-opt/coverage/instrument_coverage_cleanup.main.InstrumentCoverage.diff
@@ -6,13 +6,13 @@
       let mut _1: bool;
   
       coverage branches {
-          BlockMarkerId(0) => $DIR/instrument_coverage_cleanup.rs:14:8: 14:36 (#0)
-          BlockMarkerId(1) => $DIR/instrument_coverage_cleanup.rs:14:8: 14:36 (#0)
+          BlockMarkerId(0), BlockMarkerId(0) => $DIR/instrument_coverage_cleanup.rs:14:8: 14:36 (#0)
+          BlockMarkerId(1), BlockMarkerId(1) => $DIR/instrument_coverage_cleanup.rs:14:8: 14:36 (#0)
       }
   
 +     coverage ExpressionId(0) => Expression { lhs: Counter(0), op: Subtract, rhs: Counter(1) };
 +     coverage ExpressionId(1) => Expression { lhs: Counter(1), op: Add, rhs: Expression(0) };
-+     coverage ExpressionId(2) => Expression { lhs: Expression(0), op: Add, rhs: Counter(1) };
++     coverage ExpressionId(2) => Expression { lhs: Counter(1), op: Add, rhs: Expression(0) };
 +     coverage Code(Counter(0)) => $DIR/instrument_coverage_cleanup.rs:13:1 - 14:36;
 +     coverage Code(Expression(0)) => $DIR/instrument_coverage_cleanup.rs:14:37 - 14:39;
 +     coverage Code(Counter(1)) => $DIR/instrument_coverage_cleanup.rs:14:39 - 14:40;