Auto merge of #146700 - Zalathar:quoted-args, r=nikic

cg_llvm: Move target machine command-line quoting from C++ to Rust

When this code was introduced in rust-lang/rust#130446 and rust-lang/rust#131805, it was complicated by the need to maintain compatibility with earlier versions of LLVM.

Now that LLVM 20 is the baseline (rust-lang/rust#145071), we can do all of the quoting in pure Rust code, and pass two flat strings to LLVM to be used as-is.

---

In this PR, my priority has been to preserve the existing behaviour as much as possible, without worrying too much about what the behaviour *should* be. (Though I did avoid a leading space before the first argument.)

1 files changed, 7 insertions, 21 deletions

diff --git a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
index ab5d5c03e81..7518b40799b 100644
--- a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
@@ -271,8 +271,9 @@ extern "C" LLVMTargetMachineRef LLVMRustCreateTargetMachine(
     bool TrapUnreachable, bool Singlethread, bool VerboseAsm,
     bool EmitStackSizeSection, bool RelaxELFRelocations, bool UseInitArray,
     const char *SplitDwarfFile, const char *OutputObjFile,
-    const char *DebugInfoCompression, bool UseEmulatedTls,
-    const char *ArgsCstrBuff, size_t ArgsCstrBuffLen, bool UseWasmEH) {
+    const char *DebugInfoCompression, bool UseEmulatedTls, const char *Argv0,
+    size_t Argv0Len, const char *CommandLineArgs, size_t CommandLineArgsLen,
+    bool UseWasmEH) {
 
   auto OptLevel = fromRust(RustOptLevel);
   auto RM = fromRust(RustReloc);
@@ -343,25 +344,10 @@ extern "C" LLVMTargetMachineRef LLVMRustCreateTargetMachine(
 
   Options.EmitStackSizeSection = EmitStackSizeSection;
 
-  if (ArgsCstrBuff != nullptr) {
-    size_t buffer_offset = 0;
-    assert(ArgsCstrBuff[ArgsCstrBuffLen - 1] == '\0');
-    auto Arg0 = std::string(ArgsCstrBuff);
-    buffer_offset = Arg0.size() + 1;
-
-    std::string CommandlineArgs;
-    raw_string_ostream OS(CommandlineArgs);
-    ListSeparator LS(" ");
-    for (StringRef Arg : split(StringRef(ArgsCstrBuff + buffer_offset,
-                                         ArgsCstrBuffLen - buffer_offset),
-                               '\0')) {
-      OS << LS;
-      sys::printArg(OS, Arg, /*Quote=*/true);
-    }
-    OS.flush();
-    Options.MCOptions.Argv0 = Arg0;
-    Options.MCOptions.CommandlineArgs = CommandlineArgs;
-  }
+  if (Argv0 != nullptr)
+    Options.MCOptions.Argv0 = {Argv0, Argv0Len};
+  if (CommandLineArgs != nullptr)
+    Options.MCOptions.CommandlineArgs = {CommandLineArgs, CommandLineArgsLen};
 
 #if LLVM_VERSION_GE(21, 0)
   TargetMachine *TM = TheTarget->createTargetMachine(Trip, CPU, Feature,