When LLVM's location discriminator value limit is exceeded, emit loca… · rust-lang/rust@45ef927 (original) (raw)
`@@ -9,7 +9,7 @@ use rustc_middle::mir::{Body, SourceScope};
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`use rustc_middle::ty::layout::{FnAbiOf, HasTypingEnv};
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`use rustc_middle::ty::{self, Instance};
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`use rustc_session::config::DebugInfo;
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``
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use rustc_span::{BytePos, hygiene};
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use rustc_span::{BytePos, DUMMY_SP, hygiene};
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``
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`use super::metadata::file_metadata;
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`use super::utils::DIB;
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`@@ -85,23 +85,15 @@ fn make_mir_scope<'ll, 'tcx>(
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` discriminators,
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` parent,
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`);
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``
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if let Some(parent_scope) = debug_context.scopes[parent] {
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``
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parent_scope
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``
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} else {
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``
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// If the parent scope could not be represented then no children
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``
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// can be either.
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``
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debug_context.scopes[scope] = None;
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``
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instantiated.insert(scope);
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``
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return;
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``
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}
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debug_context.scopes[parent]
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`} else {
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`// The root is the function itself.
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`let file = cx.sess().source_map().lookup_source_file(mir.span.lo());
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``
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debug_context.scopes[scope] = Some(DebugScope {
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debug_context.scopes[scope] = DebugScope {
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`file_start_pos: file.start_pos,
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`file_end_pos: file.end_position(),
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``
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..debug_context.scopes[scope].unwrap()
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``
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});
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..debug_context.scopes[scope]
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};
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` instantiated.insert(scope);
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`return;
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`};
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`@@ -112,7 +104,7 @@ fn make_mir_scope<'ll, 'tcx>(
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`{
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`// Do not create a DIScope if there are no variables defined in this
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`` // MIR SourceScope, and it's not inlined, to avoid debuginfo bloat.
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``
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debug_context.scopes[scope] = Some(parent_scope);
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debug_context.scopes[scope] = parent_scope;
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` instantiated.insert(scope);
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`return;
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`}
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`@@ -145,14 +137,7 @@ fn make_mir_scope<'ll, 'tcx>(
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`},
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`};
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``
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``
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let mut debug_scope = Some(DebugScope {
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``
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dbg_scope,
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``
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inlined_at: parent_scope.inlined_at,
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``
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file_start_pos: loc.file.start_pos,
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``
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file_end_pos: loc.file.end_position(),
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``
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});
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``
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``
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if let Some((_, callsite_span)) = scope_data.inlined {
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let inlined_at = scope_data.inlined.map(|(_, callsite_span)| {
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`let callsite_span = hygiene::walk_chain_collapsed(callsite_span, mir.span);
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`let callsite_scope = parent_scope.adjust_dbg_scope_for_span(cx, callsite_span);
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`let loc = cx.dbg_loc(callsite_scope, parent_scope.inlined_at, callsite_span);
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`@@ -175,29 +160,29 @@ fn make_mir_scope<'ll, 'tcx>(
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`// Note further that we can't key this hashtable on the span itself,
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`// because these spans could have distinct SyntaxContexts. We have
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`// to key on exactly what we're giving to LLVM.
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``
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let inlined_at = match discriminators.entry(callsite_span.lo()) {
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match discriminators.entry(callsite_span.lo()) {
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`Entry::Occupied(mut o) => {
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`*o.get_mut() += 1;
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// NB: We have to emit something here or we'll fail LLVM IR verification
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// in at least some circumstances (see issue #135322) so if the required
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// discriminant cannot be encoded fall back to the dummy location.
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`unsafe { llvm::LLVMRustDILocationCloneWithBaseDiscriminator(loc, *o.get()) }
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.unwrap_or_else(|| {
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cx.dbg_loc(callsite_scope, parent_scope.inlined_at, DUMMY_SP)
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})
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`}
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`Entry::Vacant(v) => {
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` v.insert(0);
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``
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Some(loc)
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``
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}
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``
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};
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``
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match inlined_at {
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``
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Some(inlined_at) => {
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``
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debug_scope.as_mut().unwrap().inlined_at = Some(inlined_at);
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``
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}
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``
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None => {
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``
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// LLVM has a maximum discriminator that it can encode (currently
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// it uses 12 bits for 4096 possible values). If we exceed that
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// there is little we can do but drop the debug info.
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``
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debug_scope = None;
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loc
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`}
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`}
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``
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}
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});
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``
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debug_context.scopes[scope] = debug_scope;
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debug_context.scopes[scope] = DebugScope {
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dbg_scope,
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inlined_at: inlined_at.or(parent_scope.inlined_at),
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file_start_pos: loc.file.start_pos,
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file_end_pos: loc.file.end_position(),
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};
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` instantiated.insert(scope);
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`}
`