Rename trans to codegen everywhere.

1 files changed, 88 insertions, 0 deletions

diff --git a/src/librustc_codegen_llvm/debuginfo/gdb.rs b/src/librustc_codegen_llvm/debuginfo/gdb.rs
new file mode 100644
index 00000000000..0b4858c7ab0
--- /dev/null
+++ b/src/librustc_codegen_llvm/debuginfo/gdb.rs
@@ -0,0 +1,88 @@
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// .debug_gdb_scripts binary section.
+
+use llvm;
+
+use common::{C_bytes, CodegenCx, C_i32};
+use builder::Builder;
+use declare;
+use type_::Type;
+use rustc::session::config::NoDebugInfo;
+
+use std::ptr;
+use syntax::attr;
+
+
+/// Inserts a side-effect free instruction sequence that makes sure that the
+/// .debug_gdb_scripts global is referenced, so it isn't removed by the linker.
+pub fn insert_reference_to_gdb_debug_scripts_section_global(bx: &Builder) {
+    if needs_gdb_debug_scripts_section(bx.cx) {
+        let gdb_debug_scripts_section = get_or_insert_gdb_debug_scripts_section_global(bx.cx);
+        // Load just the first byte as that's all that's necessary to force
+        // LLVM to keep around the reference to the global.
+        let indices = [C_i32(bx.cx, 0), C_i32(bx.cx, 0)];
+        let element = bx.inbounds_gep(gdb_debug_scripts_section, &indices);
+        let volative_load_instruction = bx.volatile_load(element);
+        unsafe {
+            llvm::LLVMSetAlignment(volative_load_instruction, 1);
+        }
+    }
+}
+
+/// Allocates the global variable responsible for the .debug_gdb_scripts binary
+/// section.
+pub fn get_or_insert_gdb_debug_scripts_section_global(cx: &CodegenCx)
+                                                  -> llvm::ValueRef {
+    let c_section_var_name = "__rustc_debug_gdb_scripts_section__\0";
+    let section_var_name = &c_section_var_name[..c_section_var_name.len()-1];
+
+    let section_var = unsafe {
+        llvm::LLVMGetNamedGlobal(cx.llmod,
+                                 c_section_var_name.as_ptr() as *const _)
+    };
+
+    if section_var == ptr::null_mut() {
+        let section_name = b".debug_gdb_scripts\0";
+        let section_contents = b"\x01gdb_load_rust_pretty_printers.py\0";
+
+        unsafe {
+            let llvm_type = Type::array(&Type::i8(cx),
+                                        section_contents.len() as u64);
+
+            let section_var = declare::define_global(cx, section_var_name,
+                                                     llvm_type).unwrap_or_else(||{
+                bug!("symbol `{}` is already defined", section_var_name)
+            });
+            llvm::LLVMSetSection(section_var, section_name.as_ptr() as *const _);
+            llvm::LLVMSetInitializer(section_var, C_bytes(cx, section_contents));
+            llvm::LLVMSetGlobalConstant(section_var, llvm::True);
+            llvm::LLVMSetUnnamedAddr(section_var, llvm::True);
+            llvm::LLVMRustSetLinkage(section_var, llvm::Linkage::LinkOnceODRLinkage);
+            // This should make sure that the whole section is not larger than
+            // the string it contains. Otherwise we get a warning from GDB.
+            llvm::LLVMSetAlignment(section_var, 1);
+            section_var
+        }
+    } else {
+        section_var
+    }
+}
+
+pub fn needs_gdb_debug_scripts_section(cx: &CodegenCx) -> bool {
+    let omit_gdb_pretty_printer_section =
+        attr::contains_name(&cx.tcx.hir.krate_attrs(),
+                            "omit_gdb_pretty_printer_section");
+
+    !omit_gdb_pretty_printer_section &&
+    cx.sess().opts.debuginfo != NoDebugInfo &&
+    cx.sess().target.target.options.emit_debug_gdb_scripts
+}