[2/4] correctly count phi arguments

Commit Message

Luc Van Oostenryck April 2, 2021, 8:25 p.m. UTC

In a phi-node,pseudo_list_size() can't be used for counting its arguments
because VOIDs must be ignored.

Signed-off-by: Luc Van Oostenryck <[e-mail]>
---
 flow.c                         | 18 +++++++++++++++++-
 validation/optim/phi-count00.c | 27 +++++++++++++++++++++++++++
 2 files changed, 44 insertions(+), 1 deletion(-)
 create mode 100644 validation/optim/phi-count00.c

Patch

diff --git a/flow.c b/flow.c
index cb94fcf20834..58807432b3aa 100644
--- a/flow.c
+++ b/flow.c
@@ -189,6 +189,22 @@  out:
 	return false;
 }
 
+///
+// count the true number of argument of a phi-node
+// VOID arguments must be ignored, so pseudo_list_size() can't be used for this.
+static int phi_count(struct instruction *node)
+{
+	pseudo_t phi;
+	int n = 0;
+
+	FOR_EACH_PTR(node->phi_list, phi) {
+		if (phi == VOID)
+			continue;
+		n++;
+	} END_FOR_EACH_PTR(phi);
+	return n;
+}
+
 /*
  * When we reach here, we have:
  *  - a basic block that ends in a conditional branch and
@@ -211,7 +227,7 @@  static int try_to_simplify_bb(struct basic_block *bb, struct instruction *first,
 	 * simplify_symbol_usage()/conversion to SSA form.
 	 * No sane simplification can be done when we have this.
 	 */
-	bogus = bb_list_size(bb->parents) != pseudo_list_size(first->phi_list);
+	bogus = bb_list_size(bb->parents) != phi_count(first);
 
 	FOR_EACH_PTR(first->phi_list, phi) {
 		struct instruction *def = phi->def;
diff --git a/validation/optim/phi-count00.c b/validation/optim/phi-count00.c
new file mode 100644
index 000000000000..38db0edaea0e
--- /dev/null
+++ b/validation/optim/phi-count00.c
@@ -0,0 +1,27 @@ 
+inline int inl(int d, int e, int f)
+{
+	switch (d) {
+	case 0:
+		return e;
+	case 1:
+		return f;
+	default:
+		return 0;
+	}
+}
+
+void foo(int a, int b, int c)
+{
+	while (1) {
+		if (inl(a, b, c))
+			break;
+	}
+}
+
+/*
+ * check-name: phi-count00
+ * check-command: test-linearize -Wno-decl $file
+ *
+ * check-output-ignore
+ * check-output-pattern(0,2): phisrc
+ */