add aliasses to llvm

Author: jdonszelmann

compiler/rustc_codegen_llvm/src/llvm/ffi.rs

@@ -2662,4 +2662,12 @@ unsafe extern "C" {
 
     pub(crate) fn LLVMRustSetNoSanitizeAddress(Global: &Value);
     pub(crate) fn LLVMRustSetNoSanitizeHWAddress(Global: &Value);
+
+    pub(crate) fn LLVMAddAlias2(
+        M: &Module,
+        ValueTy: &Type,
+        AddressSpace: c_uint,
+        Aliasee: &Value,
+        Name: *const c_char,
+    );
 }

compiler/rustc_codegen_llvm/src/llvm/mod.rs

@@ -6,7 +6,7 @@ use std::str::FromStr;
 use std::string::FromUtf8Error;
 
 use libc::c_uint;
-use rustc_abi::{Align, Size, WrappingRange};
+use rustc_abi::{AddressSpace, Align, Size, WrappingRange};
 use rustc_llvm::RustString;
 
 pub(crate) use self::CallConv::*;
@@ -327,6 +327,20 @@ pub(crate) fn get_value_name(value: &Value) -> &[u8] {
     }
 }
 
+/// Safe wrapper for `LLVMAddAlias2`
+pub(crate) fn add_alias(
+    module: &Module,
+    ty: &Type,
+    address_space: AddressSpace,
+    aliasee: &Value,
+    name: &[u8],
+) {
+    unsafe {
+        let data = name.as_c_char_ptr();
+        LLVMAddAlias2(value, data, address_space, aliasee, name.len());
+    }
+}
+
 /// Safe wrapper for `LLVMSetValueName2` from a byte slice
 pub(crate) fn set_value_name(value: &Value, name: &[u8]) {
     unsafe {