Rollup merge of rust-lang#136761 - workingjubilee:specify-opt-level-for-codegen-tests, r=saethlin

tests: `-Copt-level=3` instead of `-O` in codegen tests

An effective blocker for redefining the meaning of `-O` is to stop reusing this somewhat ambiguous alias in our own codegen test suite. The choice between `-Copt-level=2` and `-Copt-level=3` is arbitrary for most of our tests. In most cases it makes no difference, so I set most of them to `-Copt-level=3`, as it will lead to slightly more "normalized" codegen.

Author: jhpratt

tests/codegen/abi-repr-ext.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 //@ revisions:x86_64 i686 aarch64-apple aarch64-windows aarch64-linux arm riscv
 

tests/codegen/align-offset.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 #![crate_type = "lib"]
 

tests/codegen/alloc-optimisation.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 #![crate_type = "lib"]
 
 #[no_mangle]

tests/codegen/array-clone.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 #![crate_type = "lib"]
 

tests/codegen/array-codegen.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O -C no-prepopulate-passes
+//@ compile-flags: -Copt-level=3 -C no-prepopulate-passes
 
 #![crate_type = "lib"]
 

tests/codegen/array-equality.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O -Z merge-functions=disabled
+//@ compile-flags: -Copt-level=3 -Z merge-functions=disabled
 //@ only-x86_64
 #![crate_type = "lib"]
 

tests/codegen/array-optimized.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 #![crate_type = "lib"]
 

tests/codegen/array-repeat.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 #![crate_type = "lib"]
 #![feature(array_repeat)]

tests/codegen/asm/goto.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 //@ only-x86_64
 
 #![crate_type = "rlib"]

tests/codegen/asm/may_unwind.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 //@ only-x86_64
 
 #![crate_type = "rlib"]

tests/codegen/asm/maybe-uninit.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 //@ only-x86_64
 
 #![crate_type = "rlib"]

tests/codegen/asm/multiple-options.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 //@ only-x86_64
 
 #![crate_type = "rlib"]

tests/codegen/asm/options.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 //@ only-x86_64
 
 #![crate_type = "rlib"]

tests/codegen/asm/x86-clobber_abi.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 //@ only-x86_64
 
 #![crate_type = "rlib"]

tests/codegen/asm/x86-clobbers.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 //@ only-x86_64
 
 #![crate_type = "rlib"]

tests/codegen/atomic-operations.rs

@@ -1,5 +1,5 @@
 // Code generation of atomic operations.
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 #![crate_type = "lib"]
 
 use std::sync::atomic::AtomicI32;

tests/codegen/atomicptr.rs

@@ -4,7 +4,7 @@
 // ensures that we do not have such a round-trip for AtomicPtr::swap, because LLVM supports pointer
 // arguments to `atomicrmw xchg`.
 
-//@ compile-flags: -O -Cno-prepopulate-passes
+//@ compile-flags: -Copt-level=3 -Cno-prepopulate-passes
 #![crate_type = "lib"]
 #![feature(strict_provenance_atomic_ptr)]
 

tests/codegen/avr/avr-func-addrspace.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O --target=avr-unknown-gnu-atmega328 --crate-type=rlib -C panic=abort
+//@ compile-flags: -Copt-level=3 --target=avr-unknown-gnu-atmega328 --crate-type=rlib -C panic=abort
 //@ needs-llvm-components: avr
 
 // This test validates that function pointers can be stored in global variables

tests/codegen/binary-heap-peek-mut-pop-no-panic.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 //@ ignore-std-debug-assertions
 #![crate_type = "lib"]
 

tests/codegen/binary-search-index-no-bound-check.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 #![crate_type = "lib"]
 
 // Make sure no bounds checks are emitted when slicing or indexing

tests/codegen/box-uninit-bytes.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 #![crate_type = "lib"]
 
 use std::mem::MaybeUninit;

tests/codegen/call-metadata.rs

@@ -1,7 +1,7 @@
 // Checks that range metadata gets emitted on calls to functions returning a
 // scalar value.
 
-//@ compile-flags: -O -C no-prepopulate-passes
+//@ compile-flags: -Copt-level=3 -C no-prepopulate-passes
 //@ max-llvm-major-version: 18
 
 #![crate_type = "lib"]

tests/codegen/cast-optimized.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O -Z merge-functions=disabled
+//@ compile-flags: -Copt-level=3 -Z merge-functions=disabled
 #![crate_type = "lib"]
 
 // This tests that LLVM can optimize based on the niches in the source or

tests/codegen/cast-target-abi.rs

@@ -1,7 +1,7 @@
 // ignore-tidy-linelength
 //@ revisions:aarch64 loongarch64 powerpc64 sparc64 x86_64
 //@ min-llvm-version: 19
-//@ compile-flags: -O -Cno-prepopulate-passes -Zlint-llvm-ir -Cllvm-args=-lint-abort-on-error
+//@ compile-flags: -Copt-level=3 -Cno-prepopulate-passes -Zlint-llvm-ir -Cllvm-args=-lint-abort-on-error
 
 //@[aarch64] compile-flags: --target aarch64-unknown-linux-gnu
 //@[aarch64] needs-llvm-components: arm

tests/codegen/catch-unwind.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 // On x86 the closure is inlined in foo() producing something like
 // define i32 @foo() [...] {

tests/codegen/char-ascii-branchless.rs

@@ -1,6 +1,6 @@
 // Checks that these functions are branchless.
 //
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 #![crate_type = "lib"]
 

tests/codegen/checked_ilog.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 #![crate_type = "lib"]
 

tests/codegen/checked_math.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O -Z merge-functions=disabled
+//@ compile-flags: -Copt-level=3 -Z merge-functions=disabled
 
 #![crate_type = "lib"]
 #![feature(unchecked_shifts)]

tests/codegen/clone_as_copy.rs

@@ -1,7 +1,7 @@
 //@ revisions: DEBUGINFO NODEBUGINFO
 //@ compile-flags: -Zunsound-mir-opts
 // FIXME: see <https://github.com/rust-lang/rust/issues/132353>
-//@ compile-flags: -O -Cno-prepopulate-passes
+//@ compile-flags: -Copt-level=3 -Cno-prepopulate-passes
 //@ [DEBUGINFO] compile-flags: -Cdebuginfo=full
 
 // From https://github.com/rust-lang/rust/issues/128081.

tests/codegen/common_prim_int_ptr.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 #![crate_type = "lib"]
 #![feature(core_intrinsics)]

tests/codegen/const-array.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 #![crate_type = "lib"]
 

tests/codegen/cross-crate-inlining/always-inline.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 //@ aux-build:always.rs
 
 #![crate_type = "lib"]

tests/codegen/cross-crate-inlining/auxiliary/always.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O -Zcross-crate-inline-threshold=always
+//@ compile-flags: -Copt-level=3 -Zcross-crate-inline-threshold=always
 
 #![crate_type = "lib"]
 

tests/codegen/cross-crate-inlining/auxiliary/leaf.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 #![crate_type = "lib"]
 

tests/codegen/cross-crate-inlining/auxiliary/never.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O -Zcross-crate-inline-threshold=never
+//@ compile-flags: -Copt-level=3 -Zcross-crate-inline-threshold=never
 
 #![crate_type = "lib"]
 

tests/codegen/cross-crate-inlining/leaf-inlining.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O -Zcross-crate-inline-threshold=yes
+//@ compile-flags: -Copt-level=3 -Zcross-crate-inline-threshold=yes
 //@ aux-build:leaf.rs
 
 #![crate_type = "lib"]

tests/codegen/cross-crate-inlining/never-inline.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 //@ aux-build:never.rs
 
 #![crate_type = "lib"]

tests/codegen/dealloc-no-unwind.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 #![crate_type = "lib"]
 

tests/codegen/debug-fndef-size.rs

@@ -1,7 +1,7 @@
 // Verify that `i32::cmp` FnDef type is declared with a size of 0 and an
 // alignment of 8 bits (1 byte) in LLVM debuginfo.
 
-//@ compile-flags: -O -g -Cno-prepopulate-passes
+//@ compile-flags: -Copt-level=3 -g -Cno-prepopulate-passes
 //@ ignore-msvc the types are mangled differently
 
 use std::cmp::Ordering;

tests/codegen/debuginfo-constant-locals.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -g -O
+//@ compile-flags: -g -Copt-level=3
 
 // Check that simple constant values are preserved in debuginfo across both MIR opts and LLVM opts
 

tests/codegen/debuginfo-inline-callsite-location.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -g -O -C panic=abort
+//@ compile-flags: -g -Copt-level=3 -C panic=abort
 
 // Check that each inline call site for the same function uses the same "sub-program" so that LLVM
 // can correctly merge the debug info if it merges the inlined code (e.g., for merging of tail

tests/codegen/deduced-param-attrs.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 #![crate_type = "lib"]
 #![allow(incomplete_features)]

tests/codegen/dont-shuffle-bswaps.rs

@@ -0,0 +1,36 @@
+//@ revisions: OPT2 OPT3
+//@[OPT2] compile-flags: -Copt-level=2
+//@[OPT3] compile-flags: -C opt-level=3
+//@ min-llvm-version: 18.1.3
+
+#![crate_type = "lib"]
+#![no_std]
+
+// The code is from https://github.com/rust-lang/rust/issues/122805.
+// Ensure we do not generate the shufflevector instruction
+// to avoid complicating the code.
+// CHECK-LABEL: define{{.*}}void @convert(
+// CHECK-NOT: shufflevector
+// On higher opt levels, this should just be a bswap:
+// OPT3: load <8 x i16>
+// OPT3-NEXT: call <8 x i16> @llvm.bswap
+// OPT3-NEXT: store <8 x i16>
+// OPT3-NEXT: ret void
+#[no_mangle]
+pub fn convert(value: [u16; 8]) -> [u8; 16] {
+    #[cfg(target_endian = "little")]
+    let bswap = u16::to_be;
+    #[cfg(target_endian = "big")]
+    let bswap = u16::to_le;
+    let addr16 = [
+        bswap(value[0]),
+        bswap(value[1]),
+        bswap(value[2]),
+        bswap(value[3]),
+        bswap(value[4]),
+        bswap(value[5]),
+        bswap(value[6]),
+        bswap(value[7]),
+    ];
+    unsafe { core::mem::transmute::<_, [u8; 16]>(addr16) }
+}

tests/codegen/drop-in-place-noalias.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O -C no-prepopulate-passes
+//@ compile-flags: -Copt-level=3 -C no-prepopulate-passes
 
 // Tests that the compiler can apply `noalias` and other &mut attributes to `drop_in_place`.
 // Note that non-Unpin types should not get `noalias`, matching &mut behavior.

tests/codegen/dst-vtable-align-nonzero.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O -Z merge-functions=disabled
+//@ compile-flags: -Copt-level=3 -Z merge-functions=disabled
 
 #![crate_type = "lib"]
 #![feature(core_intrinsics)]

tests/codegen/dst-vtable-size-range.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O -Z merge-functions=disabled
+//@ compile-flags: -Copt-level=3 -Z merge-functions=disabled
 
 #![crate_type = "lib"]
 #![feature(core_intrinsics)]

tests/codegen/emscripten-catch-unwind-js-eh.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O --target wasm32-unknown-emscripten
+//@ compile-flags: -Copt-level=3 --target wasm32-unknown-emscripten
 //@ needs-llvm-components: webassembly
 
 // Emscripten has its own unique implementation of catch_unwind (in `codegen_emcc_try`),

tests/codegen/emscripten-catch-unwind-wasm-eh.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O --target wasm32-unknown-emscripten -Z emscripten-wasm-eh
+//@ compile-flags: -Copt-level=3 --target wasm32-unknown-emscripten -Z emscripten-wasm-eh
 //@ needs-llvm-components: webassembly
 
 // Emscripten catch_unwind using wasm exceptions

tests/codegen/enum/enum-bounds-check-derived-idx.rs

@@ -1,6 +1,6 @@
 // This test checks an optimization that is not guaranteed to work. This test case should not block
 // a future LLVM update.
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 #![crate_type = "lib"]
 

tests/codegen/enum/enum-bounds-check-issue-13926.rs

@@ -1,6 +1,6 @@
 // This test checks an optimization that is not guaranteed to work. This test case should not block
 // a future LLVM update.
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 #![crate_type = "lib"]
 

tests/codegen/enum/enum-bounds-check.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 #![crate_type = "lib"]
 

tests/codegen/enum/enum-early-otherwise-branch.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 #![crate_type = "lib"]
 

tests/codegen/enum/unreachable_enum_default_branch.rs

@@ -1,4 +1,4 @@
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 
 #![crate_type = "lib"]
 

tests/codegen/error-provide.rs

@@ -1,6 +1,6 @@
 // Codegen test for #126242
 
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 #![crate_type = "lib"]
 #![feature(error_generic_member_access)]
 use std::error::Request;

tests/codegen/external-no-mangle-statics.rs

@@ -1,6 +1,6 @@
 //@ revisions: lib staticlib
 //@ ignore-emscripten default visibility is hidden
-//@ compile-flags: -O
+//@ compile-flags: -Copt-level=3
 //@ [lib] compile-flags: --crate-type lib
 //@ [staticlib] compile-flags: --crate-type staticlib
 // `#[no_mangle]`d static variables always have external linkage, i.e., no `internal` in their

tests/codegen/f128-wasm32-callconv.rs

@@ -1,7 +1,7 @@
 //! Verify that Rust implements the expected calling convention for `f128`
 
 //@ add-core-stubs
-//@ compile-flags: -O --target wasm32-wasip1
+//@ compile-flags: -Copt-level=3 --target wasm32-wasip1
 //@ needs-llvm-components: webassembly
 
 #![crate_type = "lib"]