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Diffstat (limited to '')
-rw-r--r-- | compiler/rustc_mir_build/src/build/cfg.rs | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/compiler/rustc_mir_build/src/build/cfg.rs b/compiler/rustc_mir_build/src/build/cfg.rs new file mode 100644 index 000000000..d7b4b1f73 --- /dev/null +++ b/compiler/rustc_mir_build/src/build/cfg.rs @@ -0,0 +1,113 @@ +//! Routines for manipulating the control-flow graph. + +use crate::build::CFG; +use rustc_middle::mir::*; +use rustc_middle::ty::TyCtxt; + +impl<'tcx> CFG<'tcx> { + pub(crate) fn block_data(&self, blk: BasicBlock) -> &BasicBlockData<'tcx> { + &self.basic_blocks[blk] + } + + pub(crate) fn block_data_mut(&mut self, blk: BasicBlock) -> &mut BasicBlockData<'tcx> { + &mut self.basic_blocks[blk] + } + + // llvm.org/PR32488 makes this function use an excess of stack space. Mark + // it as #[inline(never)] to keep rustc's stack use in check. + #[inline(never)] + pub(crate) fn start_new_block(&mut self) -> BasicBlock { + self.basic_blocks.push(BasicBlockData::new(None)) + } + + pub(crate) fn start_new_cleanup_block(&mut self) -> BasicBlock { + let bb = self.start_new_block(); + self.block_data_mut(bb).is_cleanup = true; + bb + } + + pub(crate) fn push(&mut self, block: BasicBlock, statement: Statement<'tcx>) { + debug!("push({:?}, {:?})", block, statement); + self.block_data_mut(block).statements.push(statement); + } + + pub(crate) fn push_assign( + &mut self, + block: BasicBlock, + source_info: SourceInfo, + place: Place<'tcx>, + rvalue: Rvalue<'tcx>, + ) { + self.push( + block, + Statement { source_info, kind: StatementKind::Assign(Box::new((place, rvalue))) }, + ); + } + + pub(crate) fn push_assign_constant( + &mut self, + block: BasicBlock, + source_info: SourceInfo, + temp: Place<'tcx>, + constant: Constant<'tcx>, + ) { + self.push_assign( + block, + source_info, + temp, + Rvalue::Use(Operand::Constant(Box::new(constant))), + ); + } + + pub(crate) fn push_assign_unit( + &mut self, + block: BasicBlock, + source_info: SourceInfo, + place: Place<'tcx>, + tcx: TyCtxt<'tcx>, + ) { + self.push_assign( + block, + source_info, + place, + Rvalue::Use(Operand::Constant(Box::new(Constant { + span: source_info.span, + user_ty: None, + literal: ConstantKind::zero_sized(tcx.types.unit), + }))), + ); + } + + pub(crate) fn push_fake_read( + &mut self, + block: BasicBlock, + source_info: SourceInfo, + cause: FakeReadCause, + place: Place<'tcx>, + ) { + let kind = StatementKind::FakeRead(Box::new((cause, place))); + let stmt = Statement { source_info, kind }; + self.push(block, stmt); + } + + pub(crate) fn terminate( + &mut self, + block: BasicBlock, + source_info: SourceInfo, + kind: TerminatorKind<'tcx>, + ) { + debug!("terminating block {:?} <- {:?}", block, kind); + debug_assert!( + self.block_data(block).terminator.is_none(), + "terminate: block {:?}={:?} already has a terminator set", + block, + self.block_data(block) + ); + self.block_data_mut(block).terminator = Some(Terminator { source_info, kind }); + } + + /// In the `origin` block, push a `goto -> target` terminator. + pub(crate) fn goto(&mut self, origin: BasicBlock, source_info: SourceInfo, target: BasicBlock) { + self.terminate(origin, source_info, TerminatorKind::Goto { target }) + } +} |