[clang] da92f2f - [AIX][Driver] Implement -mxcoff-build-id option

[Wael Yehia via cfe-commits]

Author: Wael Yehia
Date: 2023-03-27T15:36:41Z
New Revision: da92f2fb33c4e5fc570a51b0615e3d30a5b0bf8f

URL: https://github.com/llvm/llvm-project/commit/da92f2fb33c4e5fc570a51b0615e3d30a5b0bf8f
DIFF: https://github.com/llvm/llvm-project/commit/da92f2fb33c4e5fc570a51b0615e3d30a5b0bf8f.diff

LOG: [AIX][Driver] Implement -mxcoff-build-id option

The -mxcoff-build-id=0xHEXSTRING option is an alternative to the
--build-id=0xHEXSTRING linker option that is not currently available in
the AIX linker.

If HEXSTRING is an odd number of hex digits then a '0' character is prepended.
The characters ':' and '-' are not allowed (unlike the GNU linker option).
The given build-id will be saved in the string table of the loader section.

A subsequent commit will teach the profile runtime to read and use the embedded id.

Reviewed By: daltenty, qiongsiwu1, stephenpeckham

Differential Revision: https://reviews.llvm.org/D146431

Added: 
    clang/test/Driver/xcoff-build-id.c

Modified: 
    clang/include/clang/Driver/Options.td
    clang/lib/Driver/ToolChains/AIX.cpp

Removed: 
    


################################################################################
diff  --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index 2f81f60a63995..5d2089e6b3edc 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -3905,6 +3905,8 @@ defm zvector : BoolFOption<"zvector",
 def mzvector : Flag<["-"], "mzvector">, Alias<fzvector>;
 def mno_zvector : Flag<["-"], "mno-zvector">, Alias<fno_zvector>;
 
+def mxcoff_build_id_EQ : Joined<["-"], "mxcoff-build-id=">, Group<Link_Group>, MetaVarName<"<0xHEXSTRING>">,
+  HelpText<"On AIX, request creation of a build-id string, \"0xHEXSTRING\", in the string table of the loader section inside the linked binary">;
 def mignore_xcoff_visibility : Flag<["-"], "mignore-xcoff-visibility">, Group<m_Group>,
 HelpText<"Not emit the visibility attribute for asm in AIX OS or give all symbols 'unspecified' visibility in XCOFF object file">,
   Flags<[CC1Option]>;

diff  --git a/clang/lib/Driver/ToolChains/AIX.cpp b/clang/lib/Driver/ToolChains/AIX.cpp
index 711e8619d0a79..0ac261b548718 100644
--- a/clang/lib/Driver/ToolChains/AIX.cpp
+++ b/clang/lib/Driver/ToolChains/AIX.cpp
@@ -143,6 +143,22 @@ void aix::Linker::ConstructJob(Compilation &C, const JobAction &JA,
        Args.hasArg(options::OPT_coverage))
     CmdArgs.push_back("-bdbg:namedsects:ss");
 
+  if (Arg *A =
+          Args.getLastArg(clang::driver::options::OPT_mxcoff_build_id_EQ)) {
+    StringRef BuildId = A->getValue();
+    if (BuildId[0] != '0' || BuildId[1] != 'x' ||
+        BuildId.find_if_not(llvm::isHexDigit, 2) != StringRef::npos)
+      ToolChain.getDriver().Diag(diag::err_drv_unsupported_option_argument)
+          << A->getSpelling() << BuildId;
+    else {
+      std::string LinkerFlag = "-bdbg:ldrinfo:xcoff_binary_id:0x";
+      if (BuildId.size() % 2) // Prepend a 0 if odd number of digits.
+        LinkerFlag += "0";
+      LinkerFlag += BuildId.drop_front(2).lower();
+      CmdArgs.push_back(Args.MakeArgString(LinkerFlag));
+    }
+  }
+
   // Specify linker output file.
   assert((Output.isFilename() || Output.isNothing()) && "Invalid output.");
   if (Output.isFilename()) {

diff  --git a/clang/test/Driver/xcoff-build-id.c b/clang/test/Driver/xcoff-build-id.c
new file mode 100644
index 0000000000000..5f12f5b737716
--- /dev/null
+++ b/clang/test/Driver/xcoff-build-id.c
@@ -0,0 +1,14 @@
+// RUN: touch %t.o
+// RUN: %clang --target=powerpc64-ibm-aix -### %t.o -mxcoff-build-id=0x12 2>&1 | FileCheck %s
+// Test that:
+//  1) our ldrinfo flag comes before any user specified ldrinfo flag;
+//  2) upper case hex digits are converted to lower case;
+//  3) a zero is added when odd number of digits is specified in the HEXSTRING.
+// RUN: %clang --target=powerpc-ibm-aix -### %t.o -Wl,-bdbg:ldrinfo:FOO -mxcoff-build-id=0x011ffFF 2>&1 | FileCheck %s --check-prefix=OTHER
+
+// RUN: %clang --target=powerpc-ibm-aix -### %t.o -mxcoff-build-id=ff 2>&1 | FileCheck %s --check-prefix=BAD_INPUT
+// RUN: %clang --target=powerpc-ibm-aix -### %t.o -mxcoff-build-id=0x0z  2>&1 | FileCheck %s --check-prefix=BAD_INPUT
+
+CHECK: "-bdbg:ldrinfo:xcoff_binary_id:0x12"
+OTHER: "-bdbg:ldrinfo:xcoff_binary_id:0x0011ffff" {{.*}} "-bdbg:ldrinfo:FOO"
+BAD_INPUT: clang: error: unsupported argument {{.*}} to option '-mxcoff-build-id='