Generate a random name for bitcode linking when none is provided

Comgr currently uses the DataObject name to write bitcodes to the
file system, which happens whenever saving temporary files or
unbundling files. If the name provided by the caller was empty,
this led to errors.

We now generate a "comgr-anon-bitcode-XXXX.bc" string, where XXXX is
a randomly generated 3-digit number.

Change-Id: Ia701fd17acfdc07fe5569a4e1bb25b2313ded20a

lib/comgr/docs/ReleaseNotes.md

@@ -49,6 +49,9 @@ prevented correct execution of
 COMPILE\_SOURCE\_WITH\_DEVICE\_LIBS\_TO\_BC action.
 - Fixed a multi-threading bug where programs would hang when calling Comgr APIs
 like amd\_comgr\_iterate\_symbols() from multiple threads
+- Fixed an issue where providing DataObjects with an empty name to the bitcode
+linking action caused errors when AMD\_COMGR\_SAVE\_TEMPS was enabled, or when
+linking bitcode bundles.
 
 
 New APIs
@@ -104,6 +107,9 @@ metadata querys for code object v2 objects.
 deprecation of code object v3 in LLVM. However, we still test loading and
 metadata querys for code object v3 objects.
 - Revamp symbolizer test to fail on errors, among other improvments
+- Improve linking and unbundling log to correctly store temporary files in /tmp,
+and to output clang-offload-bundler command to allow users to re-create Comgr
+unbundling.
 
 New Targets
 -----------

lib/comgr/src/comgr-compiler.cpp

@@ -83,6 +83,8 @@
 
 #include "time-stat/ts-interface.h"
 
+#include <csignal>
+
 using namespace llvm;
 using namespace llvm::opt;
 using namespace llvm::sys;
@@ -1167,6 +1169,18 @@ amd_comgr_status_t AMDGPUCompiler::linkBitcodeToBitcode() {
   // Collect bitcode memory buffers from bitcodes, bundles, and archives
   for (auto *Input : InSet->DataObjects) {
 
+    if (!strcmp(Input->Name, "")) {
+      // If the calling API doesn't provide a DataObject name, generate a random
+      // string to assign. This string is used when the DataObject is written
+      // to the file system via SAVE_TEMPS, or if the object is a bundle which
+      // also needs a file system write for unpacking
+
+      char *buf = (char *) malloc(sizeof(char) * 30);
+      sprintf(buf,"comgr-anon-bitcode-%d.bc", std::rand() % 10000);
+
+      Input->Name = buf;
+    }
+
     if (env::shouldSaveTemps()) {
       if (auto Status = outputToFile(Input,
                         StringRef(std::string("./comgr_tmp_") + Input->Name))) {

lib/comgr/test/unbundle_hip_test.c

@@ -103,7 +103,7 @@ int main(int Argc, char *Argv[]) {
   checkError(Status, "amd_comgr_create_data");
   Status = amd_comgr_set_data(DataBitcode2, SizeBitcode2, BufBitcode2);
   checkError(Status, "amd_comgr_set_data");
-  Status = amd_comgr_set_data_name(DataBitcode2, "double");
+  Status = amd_comgr_set_data_name(DataBitcode2, ""); // test blank name
   checkError(Status, "amd_comgr_set_data_name");
   Status = amd_comgr_data_set_add(DataSetBundled, DataBitcode2);
   checkError(Status, "amd_comgr_data_set_add");