[llvm] [Coverage] Rework Decision/Expansion/Branch (PR #78969)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,92 @@
+// Test visualization of MC/DC constructs for branches in macro expansions.
+
+// RUN: llvm-profdata merge %S/Inputs/mcdc-macro.proftext -o %t.profdata
+// RUN: llvm-cov show --show-expansions --show-branches=count --show-mcdc %S/Inputs/mcdc-macro.o -instr-profile %t.profdata -path-equivalence=/tmp,%S/Inputs %S/Inputs/mcdc-macro.c | FileCheck %s
+
+// CHECK:  |  |  |  Branch (2:11): [Folded - Ignored]
+// CHECK:  |  |  |  Branch (3:11): [True: 0, False: 0]
+// CHECK:  |  |  |  Branch (3:23): [True: 0, False: 0]
+// CHECK:  |  Branch (9:7): [True: 0, False: 0]
+// CHECK-NEXT:  |  Branch (9:22): [True: 0, False: 0]
+// CHECK-NEXT:  ------------------
+// CHECK-NEXT:  |---> MC/DC Decision Region (9:7) to (9:23)
+// CHECK-NEXT:  |
+// CHECK-NEXT:  |  Number of Conditions: 5
+// CHECK-NEXT:  |     Condition C1 --> (9:7)
+// CHECK-NEXT:  |     Condition C2 --> (9:22)
+// CHECK-NEXT:  |     Condition C3 --> (2:11)
+// CHECK-NEXT:  |     Condition C4 --> (3:11)
+// CHECK-NEXT:  |     Condition C5 --> (3:23)
+// CHECK-NEXT:  |
+// CHECK-NEXT:  |  Executed MC/DC Test Vectors:
+// CHECK-NEXT:  |
+// CHECK-NEXT:  |     None.
+// CHECK-NEXT:  |
+// CHECK-NEXT:  |  C1-Pair: not covered
+// CHECK-NEXT:  |  C2-Pair: not covered
+// CHECK-NEXT:  |  C3-Pair: constant folded
+// CHECK-NEXT:  |  C4-Pair: not covered
+// CHECK-NEXT:  |  C5-Pair: not covered
+// CHECK-NEXT:  |  MC/DC Coverage for Decision: 0.00%
+// CHECK-NEXT:  |
+// CHECK-NEXT:  ------------------
+
+// CHECK:  |  |  |  Branch (2:11): [Folded - Ignored]
+// CHECK:  |  Branch (11:7): [True: 0, False: 0]
+// CHECK-NEXT:  ------------------
+// CHECK-NEXT:  |---> MC/DC Decision Region (11:7) to (11:13)
+// CHECK-NEXT:  |
+// CHECK-NEXT:  |  Number of Conditions: 2
+// CHECK-NEXT:  |     Condition C1 --> (11:7)
+// CHECK-NEXT:  |     Condition C2 --> (2:11)
+// CHECK-NEXT:  |
+// CHECK-NEXT:  |  Executed MC/DC Test Vectors:
+// CHECK-NEXT:  |
+// CHECK-NEXT:  |     None.
+// CHECK-NEXT:  |
+// CHECK-NEXT:  |  C1-Pair: not covered
+// CHECK-NEXT:  |  C2-Pair: constant folded
+// CHECK-NEXT:  |  MC/DC Coverage for Decision: 0.00%
+// CHECK-NEXT:  |
+// CHECK-NEXT:  ------------------
+
+// CHECK:  |  |  |  Branch (1:11): [True: 0, False: 0]
+// CHECK:  |  |  |  Branch (2:11): [Folded - Ignored]
+// CHECK:  |  |  |  |  |  Branch (3:11): [True: 0, False: 0]
+// CHECK:  |  |  |  |  |  Branch (3:23): [True: 0, False: 0]
+// CHECK:  |  Branch (13:7): [True: 0, False: 0]
+// CHECK-NEXT:  |  Branch (13:13): [True: 0, False: 0]
+// CHECK-NEXT:  ------------------
+// CHECK-NEXT:  |---> MC/DC Decision Region (13:7) to (13:32)
+// CHECK-NEXT:  |
+// CHECK-NEXT:  |  Number of Conditions: 6
+// CHECK-NEXT:  |     Condition C1 --> (13:7)
+// CHECK-NEXT:  |     Condition C2 --> (13:13)
+// CHECK-NEXT:  |     Condition C3 --> (1:11)
+// CHECK-NEXT:  |     Condition C4 --> (2:11)
+// CHECK-NEXT:  |     Condition C5 --> (3:11)
+// CHECK-NEXT:  |     Condition C6 --> (3:23)
+// CHECK-NEXT:  |
+// CHECK-NEXT:  |  Executed MC/DC Test Vectors:
+// CHECK-NEXT:  |
+// CHECK-NEXT:  |     None.
+// CHECK-NEXT:  |
+// CHECK-NEXT:  |  C1-Pair: not covered
+// CHECK-NEXT:  |  C2-Pair: not covered
+// CHECK-NEXT:  |  C3-Pair: not covered
+// CHECK-NEXT:  |  C4-Pair: constant folded
+// CHECK-NEXT:  |  C5-Pair: not covered
+// CHECK-NEXT:  |  C6-Pair: not covered
+// CHECK-NEXT:  |  MC/DC Coverage for Decision: 0.00%
+// CHECK-NEXT:  |
+// CHECK-NEXT:  ------------------
+
+Instructions for regenerating the test:
+
+# cd %S/Inputs
+cp mcdc-macro.c /tmp
+
+clang -fcoverage-mcdc -fprofile-instr-generate -fcoverage-compilation-dir=. \
+    -fcoverage-mapping /tmp/mcdc-macro.c -o /tmp/mcdc-macro.o
----------------
MaskRay wrote:

The output is an executable.

The tests have zero execution counts. Running once will make a more interesting test.

https://github.com/llvm/llvm-project/pull/78969