4 files changed, 58 insertions, 35 deletions

diff --git a/compiler/rustc_llvm/build.rs b/compiler/rustc_llvm/build.rs
index 54b22ca49a2..621363bed80 100644
--- a/compiler/rustc_llvm/build.rs
+++ b/compiler/rustc_llvm/build.rs
@@ -201,10 +201,10 @@ fn main() {
     cmd.args(&components);
 
     for lib in output(&mut cmd).split_whitespace() {
-        let name = if lib.starts_with("-l") {
-            &lib[2..]
-        } else if lib.starts_with('-') {
-            &lib[1..]
+        let name = if let Some(stripped) = lib.strip_prefix("-l") {
+            stripped
+        } else if let Some(stripped) = lib.strip_prefix('-') {
+            stripped
         } else if Path::new(lib).exists() {
             // On MSVC llvm-config will print the full name to libraries, but
             // we're only interested in the name part
@@ -241,17 +241,17 @@ fn main() {
     cmd.arg(llvm_link_arg).arg("--ldflags");
     for lib in output(&mut cmd).split_whitespace() {
         if is_crossed {
-            if lib.starts_with("-LIBPATH:") {
-                println!("cargo:rustc-link-search=native={}", lib[9..].replace(&host, &target));
-            } else if lib.starts_with("-L") {
-                println!("cargo:rustc-link-search=native={}", lib[2..].replace(&host, &target));
+            if let Some(stripped) = lib.strip_prefix("-LIBPATH:") {
+                println!("cargo:rustc-link-search=native={}", stripped.replace(&host, &target));
+            } else if let Some(stripped) = lib.strip_prefix("-L") {
+                println!("cargo:rustc-link-search=native={}", stripped.replace(&host, &target));
             }
-        } else if lib.starts_with("-LIBPATH:") {
-            println!("cargo:rustc-link-search=native={}", &lib[9..]);
-        } else if lib.starts_with("-l") {
-            println!("cargo:rustc-link-lib={}", &lib[2..]);
-        } else if lib.starts_with("-L") {
-            println!("cargo:rustc-link-search=native={}", &lib[2..]);
+        } else if let Some(stripped) = lib.strip_prefix("-LIBPATH:") {
+            println!("cargo:rustc-link-search=native={}", stripped);
+        } else if let Some(stripped) = lib.strip_prefix("-l") {
+            println!("cargo:rustc-link-lib={}", stripped);
+        } else if let Some(stripped) = lib.strip_prefix("-L") {
+            println!("cargo:rustc-link-search=native={}", stripped);
         }
     }
 
@@ -262,10 +262,10 @@ fn main() {
     let llvm_linker_flags = tracked_env_var_os("LLVM_LINKER_FLAGS");
     if let Some(s) = llvm_linker_flags {
         for lib in s.into_string().unwrap().split_whitespace() {
-            if lib.starts_with("-l") {
-                println!("cargo:rustc-link-lib={}", &lib[2..]);
-            } else if lib.starts_with("-L") {
-                println!("cargo:rustc-link-search=native={}", &lib[2..]);
+            if let Some(stripped) = lib.strip_prefix("-l") {
+                println!("cargo:rustc-link-lib={}", stripped);
+            } else if let Some(stripped) = lib.strip_prefix("-L") {
+                println!("cargo:rustc-link-search=native={}", stripped);
             }
         }
     }
diff --git a/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp
index 2b1143a4ecf..25badc3f4e1 100644
--- a/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp
@@ -3,7 +3,6 @@
 #include "llvm/ProfileData/Coverage/CoverageMappingWriter.h"
 #include "llvm/ProfileData/InstrProf.h"
 #include "llvm/ADT/ArrayRef.h"
-#include "llvm/Support/LEB128.h"
 
 #include <iostream>
 
@@ -13,15 +12,14 @@ extern "C" void LLVMRustCoverageWriteFilenamesSectionToBuffer(
     const char* const Filenames[],
     size_t FilenamesLen,
     RustStringRef BufferOut) {
-  // LLVM 11's CoverageFilenamesSectionWriter uses its new `Version4` format,
-  // so we're manually writing the `Version3` format ourselves.
-  RawRustStringOstream OS(BufferOut);
-  encodeULEB128(FilenamesLen, OS);
+  SmallVector<StringRef,32> FilenameRefs;
   for (size_t i = 0; i < FilenamesLen; i++) {
-    StringRef Filename(Filenames[i]);
-    encodeULEB128(Filename.size(), OS);
-    OS << Filename;
+    FilenameRefs.push_back(StringRef(Filenames[i]));
   }
+  auto FilenamesWriter = coverage::CoverageFilenamesSectionWriter(
+    makeArrayRef(FilenameRefs));
+  RawRustStringOstream OS(BufferOut);
+  FilenamesWriter.write(OS);
 }
 
 extern "C" void LLVMRustCoverageWriteMappingToBuffer(
@@ -45,20 +43,40 @@ extern "C" LLVMValueRef LLVMRustCoverageCreatePGOFuncNameVar(LLVMValueRef F, con
   return wrap(createPGOFuncNameVar(*cast<Function>(unwrap(F)), FuncNameRef));
 }
 
-extern "C" uint64_t LLVMRustCoverageComputeHash(const char *Name) {
-  StringRef NameRef(Name);
-  return IndexedInstrProf::ComputeHash(NameRef);
+extern "C" uint64_t LLVMRustCoverageHashCString(const char *StrVal) {
+  StringRef StrRef(StrVal);
+  return IndexedInstrProf::ComputeHash(StrRef);
+}
+
+extern "C" uint64_t LLVMRustCoverageHashByteArray(
+    const char *Bytes,
+    unsigned NumBytes) {
+  StringRef StrRef(Bytes, NumBytes);
+  return IndexedInstrProf::ComputeHash(StrRef);
 }
 
-extern "C" void LLVMRustCoverageWriteSectionNameToString(LLVMModuleRef M,
-                                                         RustStringRef Str) {
+static void WriteSectionNameToString(LLVMModuleRef M,
+                                     InstrProfSectKind SK,
+                                     RustStringRef Str) {
   Triple TargetTriple(unwrap(M)->getTargetTriple());
-  auto name = getInstrProfSectionName(IPSK_covmap,
-                                      TargetTriple.getObjectFormat());
+  auto name = getInstrProfSectionName(SK, TargetTriple.getObjectFormat());
   RawRustStringOstream OS(Str);
   OS << name;
 }
 
+extern "C" void LLVMRustCoverageWriteMapSectionNameToString(LLVMModuleRef M,
+                                                            RustStringRef Str) {
+  WriteSectionNameToString(M, IPSK_covmap, Str);
+}
+
+extern "C" void LLVMRustCoverageWriteFuncSectionNameToString(LLVMModuleRef M,
+                                                             RustStringRef Str) {
+#if LLVM_VERSION_GE(11, 0)
+  WriteSectionNameToString(M, IPSK_covfun, Str);
+// else do nothing; the `Version` check will abort codegen on the Rust side
+#endif
+}
+
 extern "C" void LLVMRustCoverageWriteMappingVarNameToString(RustStringRef Str) {
   auto name = getCoverageMappingVarName();
   RawRustStringOstream OS(Str);
@@ -66,5 +84,9 @@ extern "C" void LLVMRustCoverageWriteMappingVarNameToString(RustStringRef Str) {
 }
 
 extern "C" uint32_t LLVMRustCoverageMappingVersion() {
+#if LLVM_VERSION_GE(11, 0)
+  return coverage::CovMapVersion::Version4;
+#else
   return coverage::CovMapVersion::Version3;
+#endif
 }
diff --git a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
index 9b0c176b692..e17f933932e 100644
--- a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
@@ -1462,7 +1462,7 @@ extern "C" void LLVMRustSetComdat(LLVMModuleRef M, LLVMValueRef V,
                                   const char *Name, size_t NameLen) {
   Triple TargetTriple(unwrap(M)->getTargetTriple());
   GlobalObject *GV = unwrap<GlobalObject>(V);
-  if (!TargetTriple.isOSBinFormatMachO()) {
+  if (TargetTriple.supportsCOMDAT()) {
     StringRef NameRef(Name, NameLen);
     GV->setComdat(unwrap(M)->getOrInsertComdat(NameRef));
   }
diff --git a/compiler/rustc_llvm/src/lib.rs b/compiler/rustc_llvm/src/lib.rs
index a381290d46f..b2ffa271f62 100644
--- a/compiler/rustc_llvm/src/lib.rs
+++ b/compiler/rustc_llvm/src/lib.rs
@@ -167,6 +167,7 @@ pub fn initialize_available_targets() {
         LLVMInitializeWebAssemblyTargetInfo,
         LLVMInitializeWebAssemblyTarget,
         LLVMInitializeWebAssemblyTargetMC,
-        LLVMInitializeWebAssemblyAsmPrinter
+        LLVMInitializeWebAssemblyAsmPrinter,
+        LLVMInitializeWebAssemblyAsmParser
     );
 }