Rollup merge of rust-lang#69893 - tmiasko:cstr, r=petrochenkov

librustc_codegen_llvm: Use slices instead of 0-terminated strings

Changed functions:
* LLVMRustGetOrInsertFunction
* LLVMRustGetNamedValue
* LLVMRustBuildCall (removed unused name argument)
* LLVMRustInlineAsm
* LLVMRustInlineAsmVerify
* LLVMRustAppendModuleInlineAsm

src/librustc_codegen_llvm/allocator.rs

@@ -1,5 +1,3 @@
-use std::ffi::CString;
-
 use crate::attributes;
 use libc::c_uint;
 use rustc::bug;
@@ -50,8 +48,8 @@ pub(crate) unsafe fn codegen(tcx: TyCtxt<'_>, mods: &mut ModuleLlvm, kind: Alloc
             args.len() as c_uint,
             False,
         );
-        let name = CString::new(format!("__rust_{}", method.name)).unwrap();
-        let llfn = llvm::LLVMRustGetOrInsertFunction(llmod, name.as_ptr(), ty);
+        let name = format!("__rust_{}", method.name);
+        let llfn = llvm::LLVMRustGetOrInsertFunction(llmod, name.as_ptr().cast(), name.len(), ty);
 
         if tcx.sess.target.target.options.default_hidden_visibility {
             llvm::LLVMRustSetVisibility(llfn, llvm::Visibility::Hidden);
@@ -60,8 +58,9 @@ pub(crate) unsafe fn codegen(tcx: TyCtxt<'_>, mods: &mut ModuleLlvm, kind: Alloc
             attributes::emit_uwtable(llfn, true);
         }
 
-        let callee = CString::new(kind.fn_name(method.name)).unwrap();
-        let callee = llvm::LLVMRustGetOrInsertFunction(llmod, callee.as_ptr(), ty);
+        let callee = kind.fn_name(method.name);
+        let callee =
+            llvm::LLVMRustGetOrInsertFunction(llmod, callee.as_ptr().cast(), callee.len(), ty);
         llvm::LLVMRustSetVisibility(callee, llvm::Visibility::Hidden);
 
         let llbb = llvm::LLVMAppendBasicBlockInContext(llcx, llfn, "entry\0".as_ptr().cast());
@@ -73,14 +72,8 @@ pub(crate) unsafe fn codegen(tcx: TyCtxt<'_>, mods: &mut ModuleLlvm, kind: Alloc
             .enumerate()
             .map(|(i, _)| llvm::LLVMGetParam(llfn, i as c_uint))
             .collect::<Vec<_>>();
-        let ret = llvm::LLVMRustBuildCall(
-            llbuilder,
-            callee,
-            args.as_ptr(),
-            args.len() as c_uint,
-            None,
-            "\0".as_ptr().cast(),
-        );
+        let ret =
+            llvm::LLVMRustBuildCall(llbuilder, callee, args.as_ptr(), args.len() as c_uint, None);
         llvm::LLVMSetTailCall(ret, True);
         if output.is_some() {
             llvm::LLVMBuildRet(llbuilder, ret);

src/librustc_codegen_llvm/asm.rs

@@ -12,7 +12,6 @@ use rustc_span::Span;
 
 use libc::{c_char, c_uint};
 use log::debug;
-use std::ffi::{CStr, CString};
 
 impl AsmBuilderMethods<'tcx> for Builder<'a, 'll, 'tcx> {
     fn codegen_inline_asm(
@@ -80,12 +79,11 @@ impl AsmBuilderMethods<'tcx> for Builder<'a, 'll, 'tcx> {
             _ => self.type_struct(&output_types, false),
         };
 
-        let asm = CString::new(ia.asm.as_str().as_bytes()).unwrap();
-        let constraint_cstr = CString::new(all_constraints).unwrap();
+        let asm = ia.asm.as_str();
         let r = inline_asm_call(
             self,
             &asm,
-            &constraint_cstr,
+            &all_constraints,
             &inputs,
             output_type,
             ia.volatile,
@@ -125,17 +123,17 @@ impl AsmBuilderMethods<'tcx> for Builder<'a, 'll, 'tcx> {
 
 impl AsmMethods for CodegenCx<'ll, 'tcx> {
     fn codegen_global_asm(&self, ga: &hir::GlobalAsm) {
-        let asm = CString::new(ga.asm.as_str().as_bytes()).unwrap();
+        let asm = ga.asm.as_str();
         unsafe {
-            llvm::LLVMRustAppendModuleInlineAsm(self.llmod, asm.as_ptr());
+            llvm::LLVMRustAppendModuleInlineAsm(self.llmod, asm.as_ptr().cast(), asm.len());
         }
     }
 }
 
 fn inline_asm_call(
     bx: &mut Builder<'a, 'll, 'tcx>,
-    asm: &CStr,
-    cons: &CStr,
+    asm: &str,
+    cons: &str,
     inputs: &[&'ll Value],
     output: &'ll llvm::Type,
     volatile: bool,
@@ -157,13 +155,15 @@ fn inline_asm_call(
     let fty = bx.cx.type_func(&argtys[..], output);
     unsafe {
         // Ask LLVM to verify that the constraints are well-formed.
-        let constraints_ok = llvm::LLVMRustInlineAsmVerify(fty, cons.as_ptr());
+        let constraints_ok = llvm::LLVMRustInlineAsmVerify(fty, cons.as_ptr().cast(), cons.len());
         debug!("constraint verification result: {:?}", constraints_ok);
         if constraints_ok {
             let v = llvm::LLVMRustInlineAsm(
                 fty,
-                asm.as_ptr(),
-                cons.as_ptr(),
+                asm.as_ptr().cast(),
+                asm.len(),
+                cons.as_ptr().cast(),
+                cons.len(),
                 volatile,
                 alignstack,
                 llvm::AsmDialect::from_generic(dia),

src/librustc_codegen_llvm/builder.rs

@@ -1016,7 +1016,6 @@ impl BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
                 args.as_ptr() as *const &llvm::Value,
                 args.len() as c_uint,
                 bundle,
-                UNNAMED,
             )
         }
     }

src/librustc_codegen_llvm/declare.rs

@@ -21,7 +21,6 @@ use crate::value::Value;
 use log::debug;
 use rustc::ty::Ty;
 use rustc_codegen_ssa::traits::*;
-use rustc_data_structures::small_c_str::SmallCStr;
 
 /// Declare a function.
 ///
@@ -34,8 +33,9 @@ fn declare_raw_fn(
     ty: &'ll Type,
 ) -> &'ll Value {
     debug!("declare_raw_fn(name={:?}, ty={:?})", name, ty);
-    let namebuf = SmallCStr::new(name);
-    let llfn = unsafe { llvm::LLVMRustGetOrInsertFunction(cx.llmod, namebuf.as_ptr(), ty) };
+    let llfn = unsafe {
+        llvm::LLVMRustGetOrInsertFunction(cx.llmod, name.as_ptr().cast(), name.len(), ty)
+    };
 
     llvm::SetFunctionCallConv(llfn, callconv);
     // Function addresses in Rust are never significant, allowing functions to
@@ -83,8 +83,7 @@ impl DeclareMethods<'tcx> for CodegenCx<'ll, 'tcx> {
 
     fn get_declared_value(&self, name: &str) -> Option<&'ll Value> {
         debug!("get_declared_value(name={:?})", name);
-        let namebuf = SmallCStr::new(name);
-        unsafe { llvm::LLVMRustGetNamedValue(self.llmod, namebuf.as_ptr()) }
+        unsafe { llvm::LLVMRustGetNamedValue(self.llmod, name.as_ptr().cast(), name.len()) }
     }
 
     fn get_defined_value(&self, name: &str) -> Option<&'ll Value> {

src/librustc_codegen_llvm/llvm/ffi.rs

@@ -732,7 +732,7 @@ extern "C" {
 
     /// See Module::setModuleInlineAsm.
     pub fn LLVMSetModuleInlineAsm(M: &Module, Asm: *const c_char);
-    pub fn LLVMRustAppendModuleInlineAsm(M: &Module, Asm: *const c_char);
+    pub fn LLVMRustAppendModuleInlineAsm(M: &Module, Asm: *const c_char, AsmLen: size_t);
 
     /// See llvm::LLVMTypeKind::getTypeID.
     pub fn LLVMRustGetTypeKind(Ty: &Type) -> TypeKind;
@@ -879,13 +879,18 @@ extern "C" {
     pub fn LLVMSetThreadLocalMode(GlobalVar: &Value, Mode: ThreadLocalMode);
     pub fn LLVMIsGlobalConstant(GlobalVar: &Value) -> Bool;
     pub fn LLVMSetGlobalConstant(GlobalVar: &Value, IsConstant: Bool);
-    pub fn LLVMRustGetNamedValue(M: &Module, Name: *const c_char) -> Option<&Value>;
+    pub fn LLVMRustGetNamedValue(
+        M: &Module,
+        Name: *const c_char,
+        NameLen: size_t,
+    ) -> Option<&Value>;
     pub fn LLVMSetTailCall(CallInst: &Value, IsTailCall: Bool);
 
     // Operations on functions
     pub fn LLVMRustGetOrInsertFunction(
         M: &'a Module,
         Name: *const c_char,
+        NameLen: size_t,
         FunctionTy: &'a Type,
     ) -> &'a Value;
     pub fn LLVMSetFunctionCallConv(Fn: &Value, CC: c_uint);
@@ -1332,7 +1337,6 @@ extern "C" {
         Args: *const &'a Value,
         NumArgs: c_uint,
         Bundle: Option<&OperandBundleDef<'a>>,
-        Name: *const c_char,
     ) -> &'a Value;
     pub fn LLVMRustBuildMemCpy(
         B: &Builder<'a>,
@@ -1581,12 +1585,18 @@ extern "C" {
     pub fn LLVMRustInlineAsm(
         Ty: &Type,
         AsmString: *const c_char,
+        AsmStringLen: size_t,
         Constraints: *const c_char,
+        ConstraintsLen: size_t,
         SideEffects: Bool,
         AlignStack: Bool,
         Dialect: AsmDialect,
     ) -> &Value;
-    pub fn LLVMRustInlineAsmVerify(Ty: &Type, Constraints: *const c_char) -> bool;
+    pub fn LLVMRustInlineAsmVerify(
+        Ty: &Type,
+        Constraints: *const c_char,
+        ConstraintsLen: size_t,
+    ) -> bool;
 
     pub fn LLVMRustDebugMetadataVersion() -> u32;
     pub fn LLVMRustVersionMajor() -> u32;

src/rustllvm/RustWrapper.cpp

@@ -112,20 +112,22 @@ extern "C" void LLVMRustPrintPassTimings() {
   TimerGroup::printAll(OS);
 }
 
-extern "C" LLVMValueRef LLVMRustGetNamedValue(LLVMModuleRef M,
-                                              const char *Name) {
-  return wrap(unwrap(M)->getNamedValue(Name));
+extern "C" LLVMValueRef LLVMRustGetNamedValue(LLVMModuleRef M, const char *Name,
+                                              size_t NameLen) {
+  return wrap(unwrap(M)->getNamedValue(StringRef(Name, NameLen)));
 }
 
 extern "C" LLVMValueRef LLVMRustGetOrInsertFunction(LLVMModuleRef M,
                                                     const char *Name,
+                                                    size_t NameLen,
                                                     LLVMTypeRef FunctionTy) {
-  return wrap(
-      unwrap(M)->getOrInsertFunction(Name, unwrap<FunctionType>(FunctionTy))
+  return wrap(unwrap(M)
+                  ->getOrInsertFunction(StringRef(Name, NameLen),
+                                        unwrap<FunctionType>(FunctionTy))
 #if LLVM_VERSION_GE(9, 0)
-      .getCallee()
+                  .getCallee()
 #endif
-      );
+  );
 }
 
 extern "C" LLVMValueRef
@@ -395,22 +397,26 @@ static InlineAsm::AsmDialect fromRust(LLVMRustAsmDialect Dialect) {
   }
 }
 
-extern "C" LLVMValueRef LLVMRustInlineAsm(LLVMTypeRef Ty, char *AsmString,
-                                          char *Constraints,
-                                          LLVMBool HasSideEffects,
-                                          LLVMBool IsAlignStack,
-                                          LLVMRustAsmDialect Dialect) {
-  return wrap(InlineAsm::get(unwrap<FunctionType>(Ty), AsmString, Constraints,
+extern "C" LLVMValueRef
+LLVMRustInlineAsm(LLVMTypeRef Ty, char *AsmString, size_t AsmStringLen,
+                  char *Constraints, size_t ConstraintsLen,
+                  LLVMBool HasSideEffects, LLVMBool IsAlignStack,
+                  LLVMRustAsmDialect Dialect) {
+  return wrap(InlineAsm::get(unwrap<FunctionType>(Ty),
+                             StringRef(AsmString, AsmStringLen),
+                             StringRef(Constraints, ConstraintsLen),
                              HasSideEffects, IsAlignStack, fromRust(Dialect)));
 }
 
-extern "C" bool LLVMRustInlineAsmVerify(LLVMTypeRef Ty,
-                                          char *Constraints) {
-  return InlineAsm::Verify(unwrap<FunctionType>(Ty), Constraints);
+extern "C" bool LLVMRustInlineAsmVerify(LLVMTypeRef Ty, char *Constraints,
+                                        size_t ConstraintsLen) {
+  return InlineAsm::Verify(unwrap<FunctionType>(Ty),
+                           StringRef(Constraints, ConstraintsLen));
 }
 
-extern "C" void LLVMRustAppendModuleInlineAsm(LLVMModuleRef M, const char *Asm) {
-  unwrap(M)->appendModuleInlineAsm(StringRef(Asm));
+extern "C" void LLVMRustAppendModuleInlineAsm(LLVMModuleRef M, const char *Asm,
+                                              size_t AsmLen) {
+  unwrap(M)->appendModuleInlineAsm(StringRef(Asm, AsmLen));
 }
 
 typedef DIBuilder *LLVMRustDIBuilderRef;
@@ -1282,12 +1288,11 @@ extern "C" void LLVMRustFreeOperandBundleDef(OperandBundleDef *Bundle) {
 
 extern "C" LLVMValueRef LLVMRustBuildCall(LLVMBuilderRef B, LLVMValueRef Fn,
                                           LLVMValueRef *Args, unsigned NumArgs,
-                                          OperandBundleDef *Bundle,
-                                          const char *Name) {
+                                          OperandBundleDef *Bundle) {
   unsigned Len = Bundle ? 1 : 0;
   ArrayRef<OperandBundleDef> Bundles = makeArrayRef(Bundle, Len);
   return wrap(unwrap(B)->CreateCall(
-      unwrap(Fn), makeArrayRef(unwrap(Args), NumArgs), Bundles, Name));
+      unwrap(Fn), makeArrayRef(unwrap(Args), NumArgs), Bundles));
 }
 
 extern "C" LLVMValueRef LLVMRustBuildMemCpy(LLVMBuilderRef B,