Update to LLVM head and mark various ptrs as nonnull.

Author: luqmana

src/librustc/lib/llvm.rs

@@ -716,6 +716,9 @@ pub mod llvm {
 
         pub fn LLVMAddColdAttribute(Fn: ValueRef);
 
+        pub fn LLVMAddNonNullAttribute(Arg: ValueRef);
+        pub fn LLVMAddNonNullReturnAttribute(Fn: ValueRef);
+
         pub fn LLVMRemoveFunctionAttr(Fn: ValueRef,
                                       PA: c_ulonglong,
                                       HighPA: c_ulonglong);

src/librustc/middle/trans/base.rs

@@ -259,12 +259,14 @@ pub fn decl_rust_fn(ccx: &CrateContext, has_env: bool,
             ty::ty_uniq(..) => {
                 unsafe {
                     llvm::LLVMAddAttribute(llarg, lib::llvm::NoAliasAttribute as c_uint);
+                    llvm::LLVMAddNonNullAttribute(llarg);
                 }
             }
             // `&mut` pointer parameters never alias other parameters, or mutable global data
             ty::ty_rptr(_, mt) if mt.mutbl == ast::MutMutable => {
                 unsafe {
                     llvm::LLVMAddAttribute(llarg, lib::llvm::NoAliasAttribute as c_uint);
+                    llvm::LLVMAddNonNullAttribute(llarg);
                 }
             }
             // When a reference in an argument has no named lifetime, it's impossible for that
@@ -273,6 +275,13 @@ pub fn decl_rust_fn(ccx: &CrateContext, has_env: bool,
                 debug!("marking argument of {} as nocapture because of anonymous lifetime", name);
                 unsafe {
                     llvm::LLVMAddAttribute(llarg, lib::llvm::NoCaptureAttribute as c_uint);
+                    llvm::LLVMAddNonNullAttribute(llarg);
+                }
+            }
+            // `&` pointer parameters are never null
+            ty::ty_rptr(..) => {
+                unsafe {
+                    llvm::LLVMAddNonNullAttribute(llarg);
                 }
             }
             _ => {
@@ -290,12 +299,23 @@ pub fn decl_rust_fn(ccx: &CrateContext, has_env: bool,
 
     // The out pointer will never alias with any other pointers, as the object only exists at a
     // language level after the call. It can also be tagged with SRet to indicate that it is
-    // guaranteed to point to a usable block of memory for the type.
+    // guaranteed to point to a usable block of memory for the type. We also know that it's
+    // never null
     if uses_outptr {
         unsafe {
             let outptr = llvm::LLVMGetParam(llfn, 0);
             llvm::LLVMAddAttribute(outptr, lib::llvm::StructRetAttribute as c_uint);
             llvm::LLVMAddAttribute(outptr, lib::llvm::NoAliasAttribute as c_uint);
+            llvm::LLVMAddNonNullAttribute(outptr);
+        }
+    } else {
+        match ty::get(output).sty {
+            ty::ty_uniq(..) | ty::ty_rptr(..) => {
+                unsafe {
+                    llvm::LLVMAddNonNullReturnAttribute(llfn);
+                }
+            }
+            _ => {}
         }
     }
 

src/llvm

@@ -13,6 +13,7 @@
 #include "rustllvm.h"
 
 #include "llvm/Support/CBindingWrapping.h"
+#include "llvm/Support/FileSystem.h"
 #include "llvm/Target/TargetLibraryInfo.h"
 #include "llvm/Transforms/IPO/PassManagerBuilder.h"
 

src/rustllvm/PassWrapper.cpp

@@ -119,8 +119,20 @@ extern "C" void LLVMAddColdAttribute(LLVMValueRef Fn) {
   Function *A = unwrap<Function>(Fn);
   A->addAttribute(AttributeSet::FunctionIndex, Attribute::Cold);
 }
+
+extern "C" void LLVMAddNonNullAttribute(LLVMValueRef Arg) {
+  Argument *A = unwrap<Argument>(Arg);
+  A->addAttr(AttributeSet::get(A->getContext(), A->getArgNo() + 1, Attribute::NonNull));
+}
+
+extern "C" void LLVMAddNonNullReturnAttribute(LLVMValueRef Fn) {
+  Function *A = unwrap<Function>(Fn);
+  A->addAttribute(AttributeSet::ReturnIndex, Attribute::NonNull);
+}
 #else
 extern "C" void LLVMAddColdAttribute(LLVMValueRef Fn) {}
+extern "C" void LLVMAddNonNullAttribute(LLVMValueRef Arg) {}
+extern "C" void LLVMAddNonNullReturnAttribute(LLVMValueRef Fn) {}
 #endif
 
 extern "C" LLVMValueRef LLVMBuildAtomicLoad(LLVMBuilderRef B,

src/rustllvm/RustWrapper.cpp

@@ -1,4 +1,4 @@
 # If this file is modified, then llvm will be forcibly cleaned and then rebuilt.
 # The actual contents of this file do not matter, but to trigger a change on the
 # build bots then the contents should be changed so git updates the mtime.
-2014-04-14
+2014-05-20