Rename `rustc_mir_build::build` to `builder`

1 files changed, 137 insertions, 0 deletions

diff --git a/compiler/rustc_mir_build/src/builder/cfg.rs b/compiler/rustc_mir_build/src/builder/cfg.rs
new file mode 100644
index 00000000000..cca309115ba
--- /dev/null
+++ b/compiler/rustc_mir_build/src/builder/cfg.rs
@@ -0,0 +1,137 @@
+//! Routines for manipulating the control-flow graph.
+
+use rustc_middle::mir::*;
+use rustc_middle::ty::TyCtxt;
+use tracing::debug;
+
+use crate::builder::CFG;
+
+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: ConstOperand<'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(ConstOperand {
+                span: source_info.span,
+                user_ty: None,
+                const_: Const::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 push_place_mention(
+        &mut self,
+        block: BasicBlock,
+        source_info: SourceInfo,
+        place: Place<'tcx>,
+    ) {
+        let kind = StatementKind::PlaceMention(Box::new(place));
+        let stmt = Statement { source_info, kind };
+        self.push(block, stmt);
+    }
+
+    /// Adds a dummy statement whose only role is to associate a span with its
+    /// enclosing block for the purposes of coverage instrumentation.
+    ///
+    /// This results in more accurate coverage reports for certain kinds of
+    /// syntax (e.g. `continue` or `if !`) that would otherwise not appear in MIR.
+    pub(crate) fn push_coverage_span_marker(&mut self, block: BasicBlock, source_info: SourceInfo) {
+        let kind = StatementKind::Coverage(coverage::CoverageKind::SpanMarker);
+        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 })
+    }
+}