Auto merge of rust-lang#135763 - nikic:llvm-20, r=<try>

Update to LLVM 20

LLVM 20 GA is scheduled for March 11th. Rust 1.86 will be stable on April 3rd.

* [x] rust-lang#135764
* [x] rust-lang#136134
* [x] rust-lang/compiler-builtins#752
* [ ] llvm/llvm-project#125287
* [ ] Update compiler-builtins (blocked on rust-lang#135501)

Tested: host-x86_64, host-aarch64, apple, mingw

try-job: x86_64-msvc-1
try-job: i686-msvc-1
try-job: dist-aarch64-msvc
try-job: x86_64-msvc-ext1
try-job: x86_64-msvc-ext2
try-job: x86_64-msvc-ext3

Author: bors

compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp

@@ -22,6 +22,7 @@
 #include "llvm/Passes/StandardInstrumentations.h"
 #include "llvm/Support/CBindingWrapping.h"
 #include "llvm/Support/FileSystem.h"
+#include "llvm/Support/Program.h"
 #include "llvm/Support/TimeProfiler.h"
 #include "llvm/Support/VirtualFileSystem.h"
 #include "llvm/Target/TargetMachine.h"
@@ -472,16 +473,19 @@ extern "C" LLVMTargetMachineRef LLVMRustCreateTargetMachine(
     assert(ArgsCstrBuff[ArgsCstrBuffLen - 1] == '\0');
     auto Arg0 = std::string(ArgsCstrBuff);
     buffer_offset = Arg0.size() + 1;
-    auto ArgsCppStr = std::string(ArgsCstrBuff + buffer_offset,
-                                  ArgsCstrBuffLen - buffer_offset);
-    auto i = 0;
-    while (i != std::string::npos) {
-      i = ArgsCppStr.find('\0', i + 1);
-      if (i != std::string::npos)
-        ArgsCppStr.replace(i, 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 = ArgsCppStr;
+    Options.MCOptions.CommandlineArgs = CommandlineArgs;
 #else
     int buffer_offset = 0;
     assert(ArgsCstrBuff[ArgsCstrBuffLen - 1] == '\0');

src/llvm-project

@@ -242,7 +242,7 @@ pub unsafe extern "ptx-kernel" fn f_float_array_arg(_a: [f32; 5]) {}
 //pub unsafe extern "ptx-kernel" fn f_u128_array_arg(_a: [u128; 5]) {}
 
 // CHECK: .visible .entry f_u32_slice_arg(
-// CHECK: .param .u64 f_u32_slice_arg_param_0
+// CHECK: .param .u64 {{(\.ptr \.align 4 )?}}f_u32_slice_arg_param_0
 // CHECK: .param .u64 f_u32_slice_arg_param_1
 #[no_mangle]
 pub unsafe extern "ptx-kernel" fn f_u32_slice_arg(_a: &[u32]) {}