Rollup merge of #80521 - richkadel:llvm-coverage-counters-2.4.0, r=wesleywiser

MIR Inline is incompatible with coverage

Fixes: #80060

Fixed by disabling inlining if `-Zinstrument-coverage` is set.

The PR also adds additional use cases to the coverage test for doctests.

r? `@wesleywiser`
cc: `@tmandry`

src/test/ui/mir/mir-inlining/inline-instrument-coverage-fail.rs

@@ -0,0 +1,21 @@
+// Ensures -Zmir-opt-level=2 (specifically, inlining) is not allowed with -Zinstrument-coverage.
+// Regression test for issue #80060.
+//
+// needs-profiler-support
+// build-pass
+// compile-flags: -Zmir-opt-level=2 -Zinstrument-coverage
+#[inline(never)]
+fn foo() {}
+
+pub fn baz() {
+    bar();
+}
+
+#[inline(always)]
+fn bar() {
+    foo();
+}
+
+fn main() {
+    bar();
+}

src/test/ui/mir/mir-inlining/inline-instrument-coverage-fail.stderr

@@ -0,0 +1,2 @@
+warning: `-Z mir-opt-level=2` (or any level > 1) enables function inlining, which is incompatible with `-Z instrument-coverage`. Inlining will be disabled.
+