[compiler-rt] [AIX] Add a dummy variable in the __llvm_orderfile section (PR #81968)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-pgo

Author: Wael Yehia (w2yehia)

<details>
<summary>Changes</summary>

to satisfy the __start___llvm_orderfile reference when linking with -bexpfull and -fprofile-generate on AIX.

---
Full diff: https://github.com/llvm/llvm-project/pull/81968.diff


2 Files Affected:

- (modified) compiler-rt/lib/profile/InstrProfilingPlatformAIX.c (+3-1) 
- (added) compiler-rt/test/profile/AIX/bexpfull-pgo.c (+9) 


``````````diff
diff --git a/compiler-rt/lib/profile/InstrProfilingPlatformAIX.c b/compiler-rt/lib/profile/InstrProfilingPlatformAIX.c
index 9f46a98d78ac4e..002bec164d7e85 100644
--- a/compiler-rt/lib/profile/InstrProfilingPlatformAIX.c
+++ b/compiler-rt/lib/profile/InstrProfilingPlatformAIX.c
@@ -195,6 +195,8 @@ static const int dummy_name[0] COMPILER_RT_SECTION(
     COMPILER_RT_SEG INSTR_PROF_NAME_SECT_NAME);
 static int dummy_vnds[0] COMPILER_RT_SECTION(
     COMPILER_RT_SEG INSTR_PROF_VNODES_SECT_NAME);
+static int dummy_orderfile[0] COMPILER_RT_SECTION(
+    COMPILER_RT_SEG INSTR_PROF_ORDERFILE_SECT_NAME);
 
 // To avoid GC'ing of the dummy variables by the linker, reference them in an
 // array and reference the array in the runtime registration code
@@ -206,7 +208,7 @@ static int dummy_vnds[0] COMPILER_RT_SECTION(
 COMPILER_RT_VISIBILITY
 void *__llvm_profile_keep[] = {(void *)&dummy_cnts, (void *)&dummy_bits,
                                (void *)&dummy_data, (void *)&dummy_name,
-                               (void *)&dummy_vnds};
+                               (void *)&dummy_vnds, (void *)&dummy_orderfile};
 #ifdef __GNUC__
 #pragma GCC diagnostic pop
 #endif
diff --git a/compiler-rt/test/profile/AIX/bexpfull-pgo.c b/compiler-rt/test/profile/AIX/bexpfull-pgo.c
new file mode 100644
index 00000000000000..1be48dfdb2d3d7
--- /dev/null
+++ b/compiler-rt/test/profile/AIX/bexpfull-pgo.c
@@ -0,0 +1,9 @@
+// RUN: %clang_pgogen %s -bexpall
+// RUN: %clang_pgogen %s -bexpfull
+
+#include <string.h>
+int ar[10];
+int n;
+int main() {
+  memcpy(ar, ar + 1, n);
+};

``````````

</details>


https://github.com/llvm/llvm-project/pull/81968