From d81064949f41b95a5a2122889f07c9ffcc875834 Mon Sep 17 00:00:00 2001
From: Pavel Samolysov <samolisov@gmail.com>
Date: Wed, 18 May 2022 10:05:13 +0300
Subject: [PATCH] [ArgPromotion] Add unused-argument.ll test (NFC)

If a pointer argument is unused within the callee, this argument should
be removed from the function's signature while all used pointer
arguments should be promoted as it is expected. The ArgumentPromotion
pass doesn't touch unused non-pointer arguments at all.
---
 .../ArgumentPromotion/unused-argument.ll      | 65 +++++++++++++++++++
 1 file changed, 65 insertions(+)
 create mode 100644 llvm/test/Transforms/ArgumentPromotion/unused-argument.ll

diff --git a/llvm/test/Transforms/ArgumentPromotion/unused-argument.ll b/llvm/test/Transforms/ArgumentPromotion/unused-argument.ll
new file mode 100644
index 000000000000..f12b4bd99ee7
--- /dev/null
+++ b/llvm/test/Transforms/ArgumentPromotion/unused-argument.ll
@@ -0,0 +1,65 @@
+; RUN: opt < %s -passes=argpromotion -S | FileCheck %s
+
+; Unused pointer argument should be removed from the function's signature
+; while the used arguments should be promoted if they are pointers.
+; The pass should not touch any unused non-pointer arguments.
+define internal i32 @callee(i1 %c, i1 %d, i32* %used, i32* %unused) nounwind {
+; CHECK-LABEL: define {{[^@]+}}@callee
+; CHECK-SAME: (i1 [[C:%.*]], i1 [[D:%.*]], i32 [[USED_VAL:%.*]]) #[[ATTR0:[0-9]+]] {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br i1 [[C]], label %if, label %else
+; CHECK:       if:
+; CHECK-NEXT:    ret i32 [[USED_VAL]]
+; CHECK:       else:
+; CHECK-NEXT:    ret i32 -1
+;
+entry:
+  %x = load i32, i32* %used, align 4
+  br i1 %c, label %if, label %else
+
+if:
+  ret i32 %x
+
+else:
+  ret i32 -1
+}
+
+; Unused byval argument should be removed from the function's signature
+; while the used arguments should be promoted if they are pointers.
+; The pass should not touch any unused non-pointer arguments.
+define internal i32 @callee_byval(i1 %c, i1 %d, i32* byval(i32) align 4 %used, i32* byval(i32) align 4 %unused) nounwind {
+; CHECK-LABEL: define {{[^@]+}}@callee_byval
+; CHECK-SAME: (i1 [[C:%.*]], i1 [[D:%.*]], i32 [[USED_VAL:%.*]]) #[[ATTR0]] {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br i1 [[C]], label %if, label %else
+; CHECK:       if:
+; CHECK-NEXT:    ret i32 [[USED_VAL]]
+; CHECK:       else:
+; CHECK-NEXT:    ret i32 -1
+;
+entry:
+  %x = load i32, i32* %used, align 4
+  br i1 %c, label %if, label %else
+
+if:
+  ret i32 %x
+
+else:
+  ret i32 -1
+}
+
+define i32 @caller(i1 %c, i1 %d, i32* %arg) nounwind {
+; CHECK-LABEL: define {{[^@]+}}@caller
+; CHECK-SAME: (i1 [[C:%.*]], i1 [[D:%.*]], i32* [[ARG:%.*]]) #[[ATTR0]] {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[ARG_VAL_0:%.*]] = load i32, i32* [[ARG]], align 4
+; CHECK-NEXT:    [[RES_0:%.*]] = call i32 @callee_byval(i1 [[C]], i1 [[D]], i32 [[ARG_VAL_0]]) #[[ATTR0]]
+; CHECK-NEXT:    [[ARG_VAL_1:%.*]] = load i32, i32* [[ARG]], align 4
+; CHECK-NEXT:    [[RES_1:%.*]] = call i32 @callee(i1 [[C]], i1 [[D]], i32 [[ARG_VAL_1]]) #[[ATTR0]]
+; CHECK-NEXT:  ret i32 1
+;
+entry:
+  call i32 @callee_byval(i1 %c, i1 %d, i32* byval(i32) align 4 %arg, i32* byval(i32) align 4 %arg) nounwind
+  call i32 @callee(i1 %c, i1 %d, i32* %arg, i32* %arg) nounwind
+  ret i32 1
+}