[Xtensa]: Add '-fuse-ld' option support to ESP Xtensa toolchain

Author: andreisfr

clang/lib/Driver/ToolChains/Xtensa.cpp

@@ -214,6 +214,7 @@ void xtensa::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                   const ArgList &Args,
                                   const char *LinkingOutput) const {
   ArgStringList CmdArgs;
+  SmallString<128> Linker;
   bool WantCRTs =
       !Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles);
   const auto &ToolChain =
@@ -222,9 +223,13 @@ void xtensa::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   if (ToolChain.GCCToolchainName == "")
     llvm_unreachable("Unable to find Xtensa GCC linker");
 
-  SmallString<128> Linker(ToolChain.GCCToolchainDir);
-  llvm::sys::path::append(Linker, "bin",
-                          ToolChain.GCCToolchainName + "-" + getShortName());
+  if (Args.hasArg(options::OPT_fuse_ld_EQ)) {
+    Linker.assign(ToolChain.GetLinkerPath());
+  } else {
+    Linker.assign(ToolChain.GCCToolchainDir);
+    llvm::sys::path::append(Linker, "bin",
+                            ToolChain.GCCToolchainName + "-" + getShortName());
+  }
 
   const char *crtbegin, *crtend;
   auto RuntimeLib = ToolChain.GetRuntimeLibType(Args);

clang/test/Driver/xtensa-toolchain.c

@@ -5,7 +5,7 @@
 // RUN:   | FileCheck -check-prefix=CC1 %s
 // CC1: clang{{.*}} "-cc1" "-triple" "xtensa"
 
-// RUN: %clang %s -### -no-canonical-prefixes -fuse-ld= \
+// RUN: %clang %s -### -no-canonical-prefixes \
 // RUN:   -target xtensa --rtlib=platform \
 // RUN:   --gcc-toolchain=%S/Inputs/multilib_xtensa_tree 2>&1 \
 // RUN:   | FileCheck -check-prefix=C-XTENSA-BAREMETAL %s
@@ -14,7 +14,7 @@
 // C-XTENSA-BAREMETAL: "-L{{.*}}/Inputs/multilib_xtensa_tree/lib/gcc/xtensa-esp32-elf/8.4.0/../../..{{/|\\\\}}..{{/|\\\\}}lib{{/|\\\\}}gcc{{/|\\\\}}xtensa-esp32-elf{{/|\\\\}}8.4.0/no-rtti"
 // C-XTENSA-BAREMETAL: "-L{{.*}}/Inputs/multilib_xtensa_tree/lib/gcc/xtensa-esp32-elf/8.4.0/../../..{{/|\\\\}}..{{/|\\\\}}xtensa-esp32-elf{{/|\\\\}}lib/no-rtti"
 
-// RUN: %clang %s -### -no-canonical-prefixes -fuse-ld= \
+// RUN: %clang %s -### -no-canonical-prefixes \
 // RUN:   -target xtensa --rtlib=platform \
 // RUN:   --gcc-toolchain=%S/Inputs/multilib_xtensa_tree -frtti 2>&1 \
 // RUN:   | FileCheck -check-prefix=C-XTENSA-BAREMETAL-RTTI %s
@@ -23,7 +23,7 @@
 // C-XTENSA-BAREMETAL-RTTI: "-L{{.*}}/Inputs/multilib_xtensa_tree/lib/gcc/xtensa-esp32-elf/8.4.0/../../..{{/|\\\\}}..{{/|\\\\}}lib{{/|\\\\}}gcc{{/|\\\\}}xtensa-esp32-elf{{/|\\\\}}8.4.0"
 // C-XTENSA-BAREMETAL-RTTI: "-L{{.*}}/Inputs/multilib_xtensa_tree/lib/gcc/xtensa-esp32-elf/8.4.0/../../..{{/|\\\\}}..{{/|\\\\}}xtensa-esp32-elf{{/|\\\\}}lib"
 
-// RUN: %clang %s -### -no-canonical-prefixes -fuse-ld= \
+// RUN: %clang %s -### -no-canonical-prefixes \
 // RUN:   -target xtensa --rtlib=platform \
 // RUN:   --gcc-toolchain=%S/Inputs/multilib_xtensa_tree -mfix-esp32-psram-cache-issue 2>&1 \
 // RUN:   | FileCheck -check-prefix=C-XTENSA-BAREMETAL-PSRAM %s
@@ -32,7 +32,7 @@
 // C-XTENSA-BAREMETAL-PSRAM: "-L{{.*}}/Inputs/multilib_xtensa_tree/lib/gcc/xtensa-esp32-elf/8.4.0/../../..{{/|\\\\}}..{{/|\\\\}}lib{{/|\\\\}}gcc{{/|\\\\}}xtensa-esp32-elf{{/|\\\\}}8.4.0/esp32-psram/no-rtti"
 // C-XTENSA-BAREMETAL-PSRAM: "-L{{.*}}/Inputs/multilib_xtensa_tree/lib/gcc/xtensa-esp32-elf/8.4.0/../../..{{/|\\\\}}..{{/|\\\\}}xtensa-esp32-elf{{/|\\\\}}lib/esp32-psram/no-rtti"
 
-// RUN: %clang %s -### -no-canonical-prefixes -fuse-ld= \
+// RUN: %clang %s -### -no-canonical-prefixes \
 // RUN:   -target xtensa --rtlib=platform \
 // RUN:   --gcc-toolchain=%S/Inputs/multilib_xtensa_tree -mfix-esp32-psram-cache-issue -frtti 2>&1 \
 // RUN:   | FileCheck -check-prefix=C-XTENSA-BAREMETAL-PSRAM-RTTI %s