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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-30 03:59:35 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-30 03:59:35 +0000
commitd1b2d29528b7794b41e66fc2136e395a02f8529b (patch)
treea4a17504b260206dec3cf55b2dca82929a348ac2 /tests/codegen/intrinsics/compare_bytes.rs
parentReleasing progress-linux version 1.72.1+dfsg1-1~progress7.99u1. (diff)
downloadrustc-d1b2d29528b7794b41e66fc2136e395a02f8529b.tar.xz
rustc-d1b2d29528b7794b41e66fc2136e395a02f8529b.zip
Merging upstream version 1.73.0+dfsg1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tests/codegen/intrinsics/compare_bytes.rs')
-rw-r--r--tests/codegen/intrinsics/compare_bytes.rs34
1 files changed, 34 insertions, 0 deletions
diff --git a/tests/codegen/intrinsics/compare_bytes.rs b/tests/codegen/intrinsics/compare_bytes.rs
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+// revisions: INT32 INT16
+// compile-flags: -O
+// [INT32] ignore-16bit
+// [INT16] only-16bit
+
+#![crate_type = "lib"]
+#![feature(core_intrinsics)]
+
+use std::intrinsics::compare_bytes;
+
+#[no_mangle]
+// CHECK-LABEL: @bytes_cmp(
+pub unsafe fn bytes_cmp(a: *const u8, b: *const u8, n: usize) -> i32 {
+ // INT32: %[[TEMP:.+]] = tail call i32 @memcmp(ptr %a, ptr %b, {{i32|i64}} %n)
+ // INT32-NOT: sext
+ // INT32: ret i32 %[[TEMP]]
+
+ // INT16: %[[TEMP1:.+]] = tail call i16 @memcmp(ptr %a, ptr %b, i16 %n)
+ // INT16: %[[TEMP2:.+]] = sext i16 %[[TEMP1]] to i32
+ // INT16: ret i32 %[[TEMP2]]
+ compare_bytes(a, b, n)
+}
+
+// Ensure that, even though there's an `sext` emitted by the intrinsic,
+// that doesn't end up pessiming checks against zero.
+#[no_mangle]
+// CHECK-LABEL: @bytes_eq(
+pub unsafe fn bytes_eq(a: *const u8, b: *const u8, n: usize) -> bool {
+ // CHECK: call {{.+}} @{{bcmp|memcmp}}(ptr %a, ptr %b, {{i16|i32|i64}} %n)
+ // CHECK-NOT: sext
+ // INT32: icmp eq i32
+ // INT16: icmp eq i16
+ compare_bytes(a, b, n) == 0_i32
+}