[compiler-rt] [compiler-rt][ctx_profile] Add the instrumented contextual profiling APIs (PR #89838)

[Mircea Trofin via llvm-commits]

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@@ -20,3 +29,173 @@ TEST(ArenaTest, Basic) {
   Arena::freeArenaList(A);
   EXPECT_EQ(A, nullptr);
 }
+
+TEST_F(ContextTest, Basic) {
+  auto *Ctx = __llvm_ctx_profile_start_context(&Root, 1, 10, 4);
+  EXPECT_NE(Ctx, nullptr);
+  EXPECT_NE(Root.CurrentMem, nullptr);
+  EXPECT_EQ(Root.FirstMemBlock, Root.CurrentMem);
+  EXPECT_EQ(Ctx->size(), sizeof(ContextNode) + 10 * sizeof(uint64_t) +
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mtrofin wrote:

done.

https://github.com/llvm/llvm-project/pull/89838