There is simplifications for:
(x && 0) => 0
(x && 1) => x
(x || 0) => x
but the fourth case '(x || 1)' is missing.
This patch add the missing simplification and a small test case.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>
---
simplify.c | 7 +++++-
validation/optim/bool-simplify.c | 51 ++++++++++++++++++++++++++++++++++++++++
2 files changed, 57 insertions(+), 1 deletion(-)
create mode 100644 validation/optim/bool-simplify.c
diff --git a/simplify.c b/simplify.c
index b5cd0ea7..da12ebe8 100644
--- a/simplify.c
+++ b/simplify.c
@@ -315,6 +315,11 @@ static int simplify_constant_rightside(struct instruction *insn)
long long value = insn->src2->value;
switch (insn->opcode) {
+ case OP_OR_BOOL:
+ if (value == 1)
+ return replace_with_pseudo(insn, insn->src2);
+ goto case_neutral_zero;
+
case OP_SUB:
if (value) {
insn->opcode = OP_ADD;
@@ -324,9 +329,9 @@ static int simplify_constant_rightside(struct instruction *insn)
/* Fall through */
case OP_ADD:
case OP_OR: case OP_XOR:
- case OP_OR_BOOL:
case OP_SHL:
case OP_LSR:
+ case_neutral_zero:
if (!value)
return replace_with_pseudo(insn, insn->src1);
return 0;
diff --git a/validation/optim/bool-simplify.c b/validation/optim/bool-simplify.c
new file mode 100644
index 00000000..e0ff1c2d
--- /dev/null
+++ b/validation/optim/bool-simplify.c
@@ -0,0 +1,51 @@
+int and_0(int a)
+{
+ return a && 0;
+}
+
+int and_1(int a)
+{
+ return a && 1;
+}
+
+int or_0(int a)
+{
+ return a || 0;
+}
+
+int or_1(int a)
+{
+ return a || 1;
+}
+
+/*
+ * check-name: bool-simplify
+ * check-command: test-linearize -Wno-decl $file
+ *
+ * check-output-start
+and_0:
+.L0:
+ <entry-point>
+ ret.32 $0
+
+
+and_1:
+.L2:
+ <entry-point>
+ ret.32 %arg1
+
+
+or_0:
+.L4:
+ <entry-point>
+ ret.32 %arg1
+
+
+or_1:
+.L6:
+ <entry-point>
+ ret.32 $1
+
+
+ * check-output-end
+ */
--
2.10.2
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