Make the "entrypoint" be a special OP_ENTRY instruction instead of

a special basic block.

This removes a lot of special cases, since now flow doesn't have any
special BB to worry about. It also gives a clear definition point for
argument pseudos, and thus makes liveness tracking lose a special
case.

1 files changed, 5 insertions, 1 deletions

diff --git a/linearize.h b/linearize.h
index d67de8d..c67065a 100644
--- a/linearize.h
+++ b/linearize.h
@@ -88,6 +88,10 @@ struct instruction {
 
 enum opcode {
 	OP_BADOP,
+
+	/* Entry */
+	OP_ENTRY,
+
 	/* Terminator */
 	OP_TERMINATOR,
 	OP_RET = OP_TERMINATOR,
@@ -252,7 +256,7 @@ struct entrypoint {
 	struct symbol_list *accesses;
 	struct basic_block_list *bbs;
 	struct basic_block *active;
-	struct basic_block *entry;
+	struct instruction *entry;
 };
 
 extern void insert_select(struct basic_block *bb, struct instruction *br, struct instruction *phi, pseudo_t true, pseudo_t false);