[clang] [clang] [hexagon] handle --unwindlib arg (PR #99552)

[Brian Cain via cfe-commits]

https://github.com/androm3da updated https://github.com/llvm/llvm-project/pull/99552

>From 4729e43f3904774dbe5a06ed18a12cbddae8db03 Mon Sep 17 00:00:00 2001
From: Brian Cain <bcain at quicinc.com>
Date: Wed, 17 Jul 2024 08:08:30 -0500
Subject: [PATCH] [clang] [hexagon] handle --unwindlib arg

Signed-off-by: Brian Cain <bcain at quicinc.com>
---
 .../clang/Basic/DiagnosticDriverKinds.td      |  2 ++
 clang/lib/Driver/ToolChains/Hexagon.cpp       | 18 ++++++++--
 clang/test/Driver/hexagon-toolchain-linux.c   | 33 +++++++++++++++++++
 3 files changed, 51 insertions(+), 2 deletions(-)

diff --git a/clang/include/clang/Basic/DiagnosticDriverKinds.td b/clang/include/clang/Basic/DiagnosticDriverKinds.td
index 359c0de7f811c..2a1f58ade74a2 100644
--- a/clang/include/clang/Basic/DiagnosticDriverKinds.td
+++ b/clang/include/clang/Basic/DiagnosticDriverKinds.td
@@ -156,6 +156,8 @@ def err_drv_unsupported_rtlib_for_platform : Error<
   "unsupported runtime library '%0' for platform '%1'">;
 def err_drv_invalid_unwindlib_name : Error<
   "invalid unwind library name in argument '%0'">;
+def err_drv_unsupported_unwind_for_platform : Error<
+  "unwind library '%0' is not supported by this platform">;
 def err_drv_incompatible_unwindlib : Error<
   "--rtlib=libgcc requires --unwindlib=libgcc">;
 def err_drv_incompatible_options : Error<
diff --git a/clang/lib/Driver/ToolChains/Hexagon.cpp b/clang/lib/Driver/ToolChains/Hexagon.cpp
index 12b3b99df7ca1..691d114b7050e 100644
--- a/clang/lib/Driver/ToolChains/Hexagon.cpp
+++ b/clang/lib/Driver/ToolChains/Hexagon.cpp
@@ -366,11 +366,14 @@ constructHexagonLinkArgs(Compilation &C, const JobAction &JA,
                               options::OPT_t, options::OPT_u_Group});
     AddLinkerInputs(HTC, Inputs, Args, CmdArgs, JA);
 
+    ToolChain::UnwindLibType UNW = HTC.GetUnwindLibType(Args);
+
     if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
       if (NeedsSanitizerDeps) {
         linkSanitizerRuntimeDeps(HTC, Args, CmdArgs);
 
-        CmdArgs.push_back("-lunwind");
+        if (UNW != ToolChain::UNW_None)
+          CmdArgs.push_back("-lunwind");
       }
       if (NeedsXRayDeps)
         linkXRayRuntimeDeps(HTC, Args, CmdArgs);
@@ -618,13 +621,24 @@ HexagonToolChain::~HexagonToolChain() {}
 void HexagonToolChain::AddCXXStdlibLibArgs(const ArgList &Args,
                                            ArgStringList &CmdArgs) const {
   CXXStdlibType Type = GetCXXStdlibType(Args);
+  ToolChain::UnwindLibType UNW = GetUnwindLibType(Args);
+  if (UNW != ToolChain::UNW_None && UNW != ToolChain::UNW_CompilerRT) {
+    const Arg *A = Args.getLastArg(options::OPT_unwindlib_EQ);
+    if (A) {
+      getDriver().Diag(diag::err_drv_unsupported_unwind_for_platform)
+          << A->getValue();
+      return;
+    }
+  }
+
   switch (Type) {
   case ToolChain::CST_Libcxx:
     CmdArgs.push_back("-lc++");
     if (Args.hasArg(options::OPT_fexperimental_library))
       CmdArgs.push_back("-lc++experimental");
     CmdArgs.push_back("-lc++abi");
-    CmdArgs.push_back("-lunwind");
+    if (UNW != ToolChain::UNW_None)
+      CmdArgs.push_back("-lunwind");
     break;
 
   case ToolChain::CST_Libstdcxx:
diff --git a/clang/test/Driver/hexagon-toolchain-linux.c b/clang/test/Driver/hexagon-toolchain-linux.c
index fe32638417ea4..edbd333628747 100644
--- a/clang/test/Driver/hexagon-toolchain-linux.c
+++ b/clang/test/Driver/hexagon-toolchain-linux.c
@@ -119,3 +119,36 @@
 // CHECK010:   crt1.o
 // CHECK010:   "-L/tmp"
 // CHECK010-NOT:  "-lstandalone"
+
+// -----------------------------------------------------------------------------
+// unwindlib
+// -----------------------------------------------------------------------------
+// RUN: %clangxx --unwindlib=none \
+// RUN:    --target=hexagon-unknown-linux-musl %s -### 2>&1 \
+// RUN:    | FileCheck -check-prefix=CHECK011 %s
+// CHECK011:   InstalledDir: [[INSTALLED_DIR:.+]]
+// CHECK011:   crt1.o
+// CHECK011-NOT:  "-lunwind"
+// CHECK011-NOT:  "-lgcc_eh"
+// CHECK012-NOT:  "-lgcc_s"
+
+
+// RUN: %clangxx --rtlib=compiler-rt --unwindlib=libunwind \
+// RUN:    --target=hexagon-unknown-linux-musl %s -### 2>&1 \
+// RUN:    | FileCheck -check-prefix=CHECK012 %s
+// RUN: %clangxx \
+// RUN:    --target=hexagon-unknown-linux-musl %s -### 2>&1 \
+// RUN:    | FileCheck -check-prefix=CHECK012 %s
+// CHECK012:   InstalledDir: [[INSTALLED_DIR:.+]]
+// CHECK012:   crt1.o
+// CHECK012:  "-lunwind"
+// CHECK012-NOT:  "-lgcc_eh"
+// CHECK012-NOT:  "-lgcc_s"
+
+// RUN: not %clangxx --rtlib=compiler-rt --unwindlib=libgcc \
+// RUN:    --target=hexagon-unknown-linux-musl %s -### 2>&1 \
+// RUN:    | FileCheck -check-prefix=CHECK013 %s
+// CHECK013:  error: unwind library 'libgcc' is not supported by this platform
+// CHECK013-NOT:  "-lgcc_eh"
+// CHECK013-NOT:  "-lgcc_s"
+// CHECK013-NOT:  "-lunwind"