[libc] Fix the api-test integration test

[gchatelet]

This patch

• Revives the api-test that was broken
• Adapts PrototypeTestGen to take the list of entrypoints via a file instead of arguments. The command line was becoming too long and was rejected by the shell.
• Makes sure that symbols are present in the final library by taking their address resulting in link error.

[llvmbot]

@llvm/pr-subscribers-libc

Author: Guillaume Chatelet (gchatelet)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/79627.diff

4 Files Affected:

• (modified) libc/test/CMakeLists.txt (+4-4)
• (modified) libc/test/src/CMakeLists.txt (+20-13)
• (modified) libc/utils/HdrGen/PrototypeTestGen/CMakeLists.txt (+14-2)
• (modified) libc/utils/HdrGen/PrototypeTestGen/PrototypeTestGen.cpp (+23-6)

diff --git a/libc/test/CMakeLists.txt b/libc/test/CMakeLists.txt
index f22f2b183aca92..0773e9cf15242e 100644
--- a/libc/test/CMakeLists.txt
+++ b/libc/test/CMakeLists.txt
@@ -14,14 +14,14 @@ if(LIBC_TARGET_ARCHITECTURE_IS_GPU AND
   return()
 endif()
 
-add_subdirectory(include)
-add_subdirectory(src)
-add_subdirectory(utils)
-
 if(LLVM_LIBC_FULL_BUILD AND NOT LIBC_TARGET_OS_IS_BAREMETAL)
   add_subdirectory(IntegrationTest)
 endif()
 
+add_subdirectory(include)
+add_subdirectory(src)
+add_subdirectory(utils) # uses IntegrationTest
+
 if(NOT LLVM_LIBC_FULL_BUILD)
   return()
 endif()
diff --git a/libc/test/src/CMakeLists.txt b/libc/test/src/CMakeLists.txt
index 6bd8ace9ea71af..6a3cc9d1449880 100644
--- a/libc/test/src/CMakeLists.txt
+++ b/libc/test/src/CMakeLists.txt
@@ -82,8 +82,7 @@ if(LLVM_RUNTIMES_BUILD OR LIBC_HDRGEN_EXE)
   return()
 endif()
 
-set(public_test ${CMAKE_CURRENT_BINARY_DIR}/public_api_test.cpp)
-
+# Generate api public entrypoints.
 set(entrypoints_name_list "")
 foreach(entry IN LISTS TARGET_LLVMLIBC_ENTRYPOINTS)
   get_target_property(entry_name ${entry} "ENTRYPOINT_NAME")
@@ -91,22 +90,30 @@ foreach(entry IN LISTS TARGET_LLVMLIBC_ENTRYPOINTS)
 endforeach()
 
 # TODO: Remove these when they are added to the TableGen.
-list(REMOVE_ITEM entrypoints_name_list "__assert_fail" "__errno_location")
-list(TRANSFORM entrypoints_name_list PREPEND "-e=")
+list(REMOVE_ITEM entrypoints_name_list "prctl" "getauxval" "__stack_chk_fail")
+string(REPLACE ";" "," entrypoints_name_list "${entrypoints_name_list}")
 
-file(GLOB spec_files ${LIBC_SOURCE_DIR}/spec/*.td)
+set(public_entrypoints ${CMAKE_CURRENT_BINARY_DIR}/public_entrypoints.txt)
+file(WRITE ${public_entrypoints} "${entrypoints_name_list}")
 
 # Generate api test souce code.
+set(public_test ${CMAKE_CURRENT_BINARY_DIR}/public_api_test.cpp)
+file(GLOB spec_files ${LIBC_SOURCE_DIR}/spec/*.td)
 add_custom_command(
   OUTPUT ${public_test}
-  COMMAND $<TARGET_FILE:libc-prototype-testgen> -o ${public_test}
-          ${entrypoints_name_list}
-          -I ${LIBC_SOURCE_DIR}
-          ${LIBC_SOURCE_DIR}/config/${LIBC_TARGET_OS}/api.td
-
-  DEPENDS ${LIBC_SOURCE_DIR}/config/${LIBC_TARGET_OS}/api.td ${spec_files}
-          libc-prototype-testgen ${TARGET_PUBLIC_HEADERS}
-          ${LIBC_TARGET}
+  COMMAND
+    "$<TARGET_FILE:libc-prototype-testgen>"
+      -o ${public_test}
+      --entrypoints_file ${public_entrypoints}
+      -I ${LIBC_SOURCE_DIR}
+      ${LIBC_SOURCE_DIR}/config/${LIBC_TARGET_OS}/api.td
+  DEPENDS
+    ${LIBC_SOURCE_DIR}/config/${LIBC_TARGET_OS}/api.td
+    ${spec_files}
+    ${public_entrypoints}
+    libc-prototype-testgen
+    ${TARGET_PUBLIC_HEADERS}
+    ${LIBC_TARGET}
 )
 
 add_custom_target(libc-api-test)
diff --git a/libc/utils/HdrGen/PrototypeTestGen/CMakeLists.txt b/libc/utils/HdrGen/PrototypeTestGen/CMakeLists.txt
index 9e25c21c6b3593..331eb70b7e9891 100644
--- a/libc/utils/HdrGen/PrototypeTestGen/CMakeLists.txt
+++ b/libc/utils/HdrGen/PrototypeTestGen/CMakeLists.txt
@@ -1,5 +1,17 @@
+include(TableGen)
+
+set(LLVM_LINK_COMPONENTS Support)
+
 add_tablegen(libc-prototype-testgen LLVM_LIBC
   PrototypeTestGen.cpp
 )
-target_link_libraries(libc-prototype-testgen PRIVATE LibcTableGenUtil)
-target_include_directories(libc-prototype-testgen PRIVATE ${LIBC_SOURCE_DIR})
+target_link_libraries(libc-prototype-testgen
+  PRIVATE
+    LibcTableGenUtil
+)
+target_include_directories(libc-prototype-testgen
+  PRIVATE
+    ${LIBC_SOURCE_DIR}
+    ${LLVM_INCLUDE_DIR}
+    ${LLVM_MAIN_INCLUDE_DIR}
+)
diff --git a/libc/utils/HdrGen/PrototypeTestGen/PrototypeTestGen.cpp b/libc/utils/HdrGen/PrototypeTestGen/PrototypeTestGen.cpp
index 551b97caf81fd6..b1f89fbea0256d 100644
--- a/libc/utils/HdrGen/PrototypeTestGen/PrototypeTestGen.cpp
+++ b/libc/utils/HdrGen/PrototypeTestGen/PrototypeTestGen.cpp
@@ -8,16 +8,19 @@
 
 #include "utils/LibcTableGenUtil/APIIndexer.h"
 
+#include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/CommandLine.h"
+#include "llvm/Support/MemoryBuffer.h"
 #include "llvm/TableGen/Main.h"
 #include "llvm/TableGen/Record.h"
 
 namespace {
 
-llvm::cl::list<std::string>
-    EntrypointNamesOption("e", llvm::cl::desc("<list of entrypoints>"),
-                          llvm::cl::OneOrMore);
+llvm::cl::opt<std::string> EntrypointsFilename(
+    "entrypoints_file",
+    llvm::cl::desc("file containing the comma separated list of entrypoints"),
+    llvm::cl::Required);
 
 } // anonymous namespace
 
@@ -25,7 +28,13 @@ bool TestGeneratorMain(llvm::raw_ostream &OS, llvm::RecordKeeper &records) {
   OS << "#include \"src/__support/CPP/type_traits.h\"\n";
   llvm_libc::APIIndexer G(records);
   std::unordered_set<std::string> headerFileSet;
-  for (const auto &entrypoint : EntrypointNamesOption) {
+
+  auto Entrypoints = llvm::MemoryBuffer::getFile(EntrypointsFilename);
+
+  std::vector<std::string> entrypoints;
+  for (auto entrypoint : llvm::split((*Entrypoints)->getBuffer(), ','))
+    entrypoints.push_back(entrypoint.str());
+  for (auto entrypoint : entrypoints) {
     if (entrypoint == "errno")
       continue;
     auto match = G.FunctionToHeaderMap.find(entrypoint);
@@ -48,7 +57,7 @@ bool TestGeneratorMain(llvm::raw_ostream &OS, llvm::RecordKeeper &records) {
   OS << '\n';
 
   OS << "extern \"C\" int main() {\n";
-  for (const auto &entrypoint : EntrypointNamesOption) {
+  for (const auto &entrypoint : entrypoints) {
     if (entrypoint == "errno")
       continue;
     auto match = G.FunctionSpecMap.find(entrypoint);
@@ -91,9 +100,17 @@ bool TestGeneratorMain(llvm::raw_ostream &OS, llvm::RecordKeeper &records) {
        << " prototype in TableGen does not match public header" << '"';
     OS << ");\n";
   }
+  OS << '\n';
+  OS << "  // Check that all entrypoints are present in the binary";
+  OS << "  uintptr_t check = 0;\n";
+  for (const auto &entrypoint : entrypoints) {
+    if (entrypoint == "errno")
+      continue;
+    OS << "  check += reinterpret_cast<uintptr_t>(&" << entrypoint << ");\n";
+  }
 
   OS << '\n';
-  OS << "  return 0;\n";
+  OS << "  return check != 0 ? 0 : 1;\n";
   OS << "}\n\n";
 
   return false;

[gchatelet]

This needs #79319 to be in first.