src/librustc_codegen_llvm/debuginfo/source_loc.rs

   1 use super::metadata::{UNKNOWN_COLUMN_NUMBER, UNKNOWN_LINE_NUMBER};
   2 use super::utils::debug_context;
   3
   4 use crate::common::CodegenCx;
   5 use crate::llvm::debuginfo::DIScope;
   6 use crate::llvm::{self, Value};
   7 use rustc_codegen_ssa::traits::*;
   8
   9 use rustc_data_structures::sync::Lrc;
  10 use rustc_span::{BytePos, Pos, SourceFile, SourceFileAndLine, Span};
  11
  12 /// A source code location used to generate debug information.
  13 pub struct DebugLoc {
  14     /// Information about the original source file.
  15     pub file: Lrc<SourceFile>,
  16     /// The (1-based) line number.
  17     pub line: Option<u32>,
  18     /// The (1-based) column number.
  19     pub col: Option<u32>,
  20 }
  21
  22 impl CodegenCx<'ll, '_> {
  23     /// Looks up debug source information about a `BytePos`.
  24     pub fn lookup_debug_loc(&self, pos: BytePos) -> DebugLoc {
  25         let (file, line, col) = match self.sess().source_map().lookup_line(pos) {
  26             Ok(SourceFileAndLine { sf: file, line }) => {
  27                 let line_pos = file.line_begin_pos(pos);
  28
  29                 // Use 1-based indexing.
  30                 let line = (line + 1) as u32;
  31                 let col = (pos - line_pos).to_u32() + 1;
  32
  33                 (file, Some(line), Some(col))
  34             }
  35             Err(file) => (file, None, None),
  36         };
  37
  38         // For MSVC, omit the column number.
  39         // Otherwise, emit it. This mimics clang behaviour.
  40         // See discussion in https://github.com/rust-lang/rust/issues/42921
  41         if self.sess().target.target.options.is_like_msvc {
  42             DebugLoc { file, line, col: None }
  43         } else {
  44             DebugLoc { file, line, col }
  45         }
  46     }
  47
  48     pub fn create_debug_loc(&self, scope: &'ll DIScope, span: Span) -> &'ll Value {
  49         let DebugLoc { line, col, .. } = self.lookup_debug_loc(span.lo());
  50
  51         unsafe {
  52             llvm::LLVMRustDIBuilderCreateDebugLocation(
  53                 debug_context(self).llcontext,
  54                 line.unwrap_or(UNKNOWN_LINE_NUMBER),
  55                 col.unwrap_or(UNKNOWN_COLUMN_NUMBER),
  56                 scope,
  57                 None,
  58             )
  59         }
  60     }
  61 }