use rustc_ast::attr;
use rustc_codegen_ssa::base::collect_debugger_visualizers_transitive;
use rustc_codegen_ssa::traits::*;
use rustc_hir::def_id::LOCAL_CRATE;
use rustc_middle::bug;
use rustc_middle::middle::debugger_visualizer::DebuggerVisualizerType;
use rustc_session::config::{CrateType, DebugInfo};
use rustc_span::symbol::sym;
use crate::builder::Builder;
use crate::common::CodegenCx;
use crate::llvm;
use crate::value::Value;
pub(crate) fn insert_reference_to_gdb_debug_scripts_section_global(bx: &mut Builder<'_, '_, '_>) {
if needs_gdb_debug_scripts_section(bx) {
let gdb_debug_scripts_section = get_or_insert_gdb_debug_scripts_section_global(bx);
let volatile_load_instruction = bx.volatile_load(bx.type_i8(), gdb_debug_scripts_section);
unsafe {
llvm::LLVMSetAlignment(volatile_load_instruction, 1);
}
}
}
pub(crate) fn get_or_insert_gdb_debug_scripts_section_global<'ll>(
cx: &CodegenCx<'ll, '_>,
) -> &'ll Value {
let c_section_var_name = c"__rustc_debug_gdb_scripts_section__";
let section_var_name = c_section_var_name.to_str().unwrap();
let section_var = unsafe { llvm::LLVMGetNamedGlobal(cx.llmod, c_section_var_name.as_ptr()) };
section_var.unwrap_or_else(|| {
let mut section_contents = Vec::new();
section_contents.extend_from_slice(b"\x01gdb_load_rust_pretty_printers.py\0");
let visualizers = collect_debugger_visualizers_transitive(
cx.tcx,
DebuggerVisualizerType::GdbPrettyPrinter,
);
let crate_name = cx.tcx.crate_name(LOCAL_CRATE);
for (index, visualizer) in visualizers.iter().enumerate() {
section_contents.extend_from_slice(b"\x04");
let vis_name = format!("pretty-printer-{crate_name}-{index}\n");
section_contents.extend_from_slice(vis_name.as_bytes());
section_contents.extend_from_slice(&visualizer.src);
section_contents.extend_from_slice(b"\0");
}
unsafe {
let section_contents = section_contents.as_slice();
let llvm_type = cx.type_array(cx.type_i8(), section_contents.len() as u64);
let section_var = cx
.define_global(section_var_name, llvm_type)
.unwrap_or_else(|| bug!("symbol `{}` is already defined", section_var_name));
llvm::LLVMSetSection(section_var, c".debug_gdb_scripts".as_ptr());
llvm::LLVMSetInitializer(section_var, cx.const_bytes(section_contents));
llvm::LLVMSetGlobalConstant(section_var, llvm::True);
llvm::LLVMSetUnnamedAddress(section_var, llvm::UnnamedAddr::Global);
llvm::LLVMRustSetLinkage(section_var, llvm::Linkage::LinkOnceODRLinkage);
llvm::LLVMSetAlignment(section_var, 1);
section_var
}
})
}
pub(crate) fn needs_gdb_debug_scripts_section(cx: &CodegenCx<'_, '_>) -> bool {
let omit_gdb_pretty_printer_section =
attr::contains_name(cx.tcx.hir().krate_attrs(), sym::omit_gdb_pretty_printer_section);
let embed_visualizers = cx.tcx.crate_types().iter().any(|&crate_type| match crate_type {
CrateType::Executable | CrateType::Dylib | CrateType::Cdylib | CrateType::Staticlib => {
true
}
CrateType::ProcMacro => {
false
}
CrateType::Rlib => {
false
}
});
!omit_gdb_pretty_printer_section
&& cx.sess().opts.debuginfo != DebugInfo::None
&& cx.sess().target.emit_debug_gdb_scripts
&& embed_visualizers
}