T0b1/wasmtime
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Inline resolve_undef_vars, and collapse the resulting redundancy.

Browse Source
This commit is contained in:
Dan Gohman
2017-08-31 14:49:53 -07:00
parent 2d9b902d2e
commit 79f257060f
1 changed files with 5 additions and 30 deletions
Download Patch File Download Diff File Expand all files Collapse all files

35
lib/frontend/src/ssa.rs
View File

@@ -334,6 +334,8 @@ where
///
/// This method modifies the function's `Layout` by adding arguments to the `Ebb`s to
/// take into account the Phi function placed by the SSA algorithm.
///
/// Returns the list of newly created ebbs for critical edge splitting.
pub fn seal_ebb_header_block(
&mut self,
ebb: Ebb,
@@ -343,42 +345,13 @@ where
) -> SideEffects {
let block = self.header_block(ebb);
// Sanity check
match self.blocks[block] {
BlockData::EbbBody { .. } => panic!("you can't seal an Ebb body block"),
BlockData::EbbHeader(ref data) => {
assert!(!data.sealed);
}
}
// Recurse over the predecessors to find good definitions.
let side_effects = self.resolve_undef_vars(block, dfg, layout, jts);
// Then we mark the block as sealed.
match self.blocks[block] {
BlockData::EbbBody { .. } => panic!("this should not happen"),
BlockData::EbbHeader(ref mut data) => data.sealed = true,
};
side_effects
}
// For each undef_var in an Ebb header block, lookup in the predecessors to append the right
// jump argument to the branch instruction.
// Panics if called with a non-header block.
// Returns the list of newly created ebbs for critical edge splitting.
fn resolve_undef_vars(
&mut self,
block: Block,
dfg: &mut DataFlowGraph,
layout: &mut Layout,
jts: &mut JumpTables,
) -> SideEffects {
// TODO: find a way to not allocate vectors
let (predecessors, undef_vars, ebb): (Vec<(Block, Inst)>,
Vec<(Variable, Value)>,
Ebb) = match self.blocks[block] {
BlockData::EbbBody { .. } => panic!("this should not happen"),
BlockData::EbbHeader(ref mut data) => {
assert!(!data.sealed);
(
data.predecessors.clone(),
data.undef_variables.clone(),
@@ -406,7 +379,9 @@ where
match self.blocks[block] {
BlockData::EbbBody { .. } => panic!("this should not happen"),
BlockData::EbbHeader(ref mut data) => {
assert!(!data.sealed);
data.undef_variables.clear();
data.sealed = true;
}
};
side_effects