Simplify encoding a bit.
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@ -234,13 +234,17 @@ fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
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s.source_file_cache =
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s.source_file_cache =
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(source_map.files()[source_file_index].clone(), source_file_index);
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(source_map.files()[source_file_index].clone(), source_file_index);
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}
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}
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let (ref source_file, source_file_index) = s.source_file_cache;
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if !s.source_file_cache.0.contains(span.hi) {
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if !source_file.contains(span.hi) {
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// Unfortunately, macro expansion still sometimes generates Spans
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// Unfortunately, macro expansion still sometimes generates Spans
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// that malformed in this way.
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// that malformed in this way.
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return TAG_PARTIAL_SPAN.encode(s);
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return TAG_PARTIAL_SPAN.encode(s);
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}
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}
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// Length is independent of the span provenance.
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let len = span.hi - span.lo;
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// There are two possible cases here:
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// There are two possible cases here:
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// 1. This span comes from a 'foreign' crate - e.g. some crate upstream of the
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// 1. This span comes from a 'foreign' crate - e.g. some crate upstream of the
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// crate we are writing metadata for. When the metadata for *this* crate gets
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// crate we are writing metadata for. When the metadata for *this* crate gets
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@ -257,47 +261,44 @@ fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
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// if we're a proc-macro crate.
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// if we're a proc-macro crate.
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// This allows us to avoid loading the dependencies of proc-macro crates: all of
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// This allows us to avoid loading the dependencies of proc-macro crates: all of
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// the information we need to decode `Span`s is stored in the proc-macro crate.
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// the information we need to decode `Span`s is stored in the proc-macro crate.
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let (tag, lo, hi, metadata_index) =
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let (tag, lo, metadata_index) = if source_file.is_imported() && !s.is_proc_macro {
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if s.source_file_cache.0.is_imported() && !s.is_proc_macro {
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// To simplify deserialization, we 'rebase' this span onto the crate it originally came from
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// To simplify deserialization, we 'rebase' this span onto the crate it originally came from
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// (the crate that 'owns' the file it references. These rebased 'lo' and 'hi' values
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// (the crate that 'owns' the file it references. These rebased 'lo' and 'hi' values
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// are relative to the source map information for the 'foreign' crate whose CrateNum
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// are relative to the source map information for the 'foreign' crate whose CrateNum
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// we write into the metadata. This allows `imported_source_files` to binary
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// we write into the metadata. This allows `imported_source_files` to binary
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// search through the 'foreign' crate's source map information, using the
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// search through the 'foreign' crate's source map information, using the
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// deserialized 'lo' and 'hi' values directly.
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// deserialized 'lo' and 'hi' values directly.
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//
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//
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// All of this logic ensures that the final result of deserialization is a 'normal'
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// All of this logic ensures that the final result of deserialization is a 'normal'
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// Span that can be used without any additional trouble.
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// Span that can be used without any additional trouble.
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let (external_start_pos, metadata_index) = {
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let (external_start_pos, metadata_index) = {
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// Introduce a new scope so that we drop the 'lock()' temporary
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// Introduce a new scope so that we drop the 'lock()' temporary
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match &*source_file.external_src.lock() {
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match &*s.source_file_cache.0.external_src.lock() {
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ExternalSource::Foreign { original_start_pos, metadata_index, .. } => {
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ExternalSource::Foreign { original_start_pos, metadata_index, .. } => {
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(*original_start_pos, *metadata_index)
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(*original_start_pos, *metadata_index)
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}
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src => panic!("Unexpected external source {:?}", src),
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}
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}
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};
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src => panic!("Unexpected external source {:?}", src),
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let lo = (span.lo - s.source_file_cache.0.start_pos) + external_start_pos;
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}
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let hi = (span.hi - s.source_file_cache.0.start_pos) + external_start_pos;
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(TAG_VALID_SPAN_FOREIGN, lo, hi, metadata_index)
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} else {
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// Record the fact that we need to encode the data for this `SourceFile`
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let source_files =
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s.required_source_files.as_mut().expect("Already encoded SourceMap!");
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let (source_file_index, _) = source_files.insert_full(s.source_file_cache.1);
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let source_file_index: u32 =
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source_file_index.try_into().expect("cannot export more than U32_MAX files");
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(TAG_VALID_SPAN_LOCAL, span.lo, span.hi, source_file_index)
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};
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};
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let lo = (span.lo - source_file.start_pos) + external_start_pos;
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(TAG_VALID_SPAN_FOREIGN, lo, metadata_index)
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} else {
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// Record the fact that we need to encode the data for this `SourceFile`
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let source_files =
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s.required_source_files.as_mut().expect("Already encoded SourceMap!");
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let (metadata_index, _) = source_files.insert_full(source_file_index);
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let metadata_index: u32 =
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metadata_index.try_into().expect("cannot export more than U32_MAX files");
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(TAG_VALID_SPAN_LOCAL, span.lo, metadata_index)
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};
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tag.encode(s);
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tag.encode(s);
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lo.encode(s);
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lo.encode(s);
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// Encode length which is usually less than span.hi and profits more
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// Encode length which is usually less than span.hi and profits more
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// from the variable-length integer encoding that we use.
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// from the variable-length integer encoding that we use.
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let len = hi - lo;
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len.encode(s);
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len.encode(s);
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// Encode the index of the `SourceFile` for the span, in order to make decoding faster.
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// Encode the index of the `SourceFile` for the span, in order to make decoding faster.
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