Auto merge of rust-lang#128785 - matthiaskrgr:rollup-13chr4m, r=matthiaskrgr

Rollup of 5 pull requests

Successful merges:

 - rust-lang#128384 (Add tests to ensure MTE tags are preserved across FFI boundaries)
 - rust-lang#128407 (Migrate `min-global-align` and `no-alloc-shim` `run-make` tests to rmake)
 - rust-lang#128584 (Add a set of tests for LLVM 19)
 - rust-lang#128636 (migrate `thumb-none-cortex-m` to rmake)
 - rust-lang#128696 (Migrate `staticlib-dylib-linkage` `run-make` test to rmake)

Failed merges:

 - rust-lang#128639 (migrate `thumb-none-qemu` to rmake)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

src/tools/compiletest/src/command-list.rs

@@ -170,6 +170,7 @@ const KNOWN_DIRECTIVE_NAMES: &[&str] = &[
     "only-32bit",
     "only-64bit",
     "only-aarch64",
+    "only-aarch64-unknown-linux-gnu",
     "only-apple",
     "only-arm",
     "only-avr",

src/tools/run-make-support/src/assertion_helpers.rs

@@ -77,6 +77,20 @@ pub fn assert_not_contains_regex<H: AsRef<str>, N: AsRef<str>>(haystack: H, need
     }
 }
 
+/// Assert that `haystack` contains `needle` a `count` number of times.
+#[track_caller]
+pub fn assert_count_is<H: AsRef<str>, N: AsRef<str>>(count: usize, haystack: H, needle: N) {
+    let haystack = haystack.as_ref();
+    let needle = needle.as_ref();
+    if count != haystack.matches(needle).count() {
+        eprintln!("=== HAYSTACK ===");
+        eprintln!("{}", haystack);
+        eprintln!("=== NEEDLE ===");
+        eprintln!("{}", needle);
+        panic!("needle did not appear {count} times in haystack");
+    }
+}
+
 /// Assert that all files in `dir1` exist and have the same content in `dir2`
 pub fn assert_dirs_are_equal(dir1: impl AsRef<Path>, dir2: impl AsRef<Path>) {
     let dir2 = dir2.as_ref();

src/tools/run-make-support/src/lib.rs

@@ -86,7 +86,7 @@ pub use path_helpers::{
 pub use scoped_run::{run_in_tmpdir, test_while_readonly};
 
 pub use assertion_helpers::{
-    assert_contains, assert_contains_regex, assert_dirs_are_equal, assert_equals,
+    assert_contains, assert_contains_regex, assert_count_is, assert_dirs_are_equal, assert_equals,
     assert_not_contains, assert_not_contains_regex,
 };
 

src/tools/tidy/src/allowed_run_make_makefiles.txt

@@ -13,19 +13,15 @@ run-make/libtest-json/Makefile
 run-make/libtest-junit/Makefile
 run-make/libtest-thread-limit/Makefile
 run-make/macos-deployment-target/Makefile
-run-make/min-global-align/Makefile
 run-make/native-link-modifier-bundle/Makefile
-run-make/no-alloc-shim/Makefile
 run-make/pdb-buildinfo-cl-cmd/Makefile
 run-make/pgo-indirect-call-promotion/Makefile
 run-make/remap-path-prefix-dwarf/Makefile
 run-make/reproducible-build/Makefile
 run-make/rlib-format-packed-bundled-libs/Makefile
 run-make/split-debuginfo/Makefile
-run-make/staticlib-dylib-linkage/Makefile
 run-make/symbol-mangling-hashed/Makefile
 run-make/sysroot-crates-are-unstable/Makefile
-run-make/thumb-none-cortex-m/Makefile
 run-make/thumb-none-qemu/Makefile
 run-make/translation/Makefile
 run-make/x86_64-fortanix-unknown-sgx-lvi/Makefile

tests/codegen/issues/issue-107681-unwrap_unchecked.rs

@@ -0,0 +1,20 @@
+//@ compile-flags: -O
+//@ min-llvm-version: 19
+
+// Test for #107681.
+// Make sure we don't create `br` or `select` instructions.
+
+#![crate_type = "lib"]
+
+use std::iter::Copied;
+use std::slice::Iter;
+
+#[no_mangle]
+pub unsafe fn foo(x: &mut Copied<Iter<'_, u32>>) -> u32 {
+    // CHECK-LABEL: @foo(
+    // CHECK-NOT: br
+    // CHECK-NOT: select
+    // CHECK: [[RET:%.*]] = load i32, ptr
+    // CHECK-NEXT: ret i32 [[RET]]
+    x.next().unwrap_unchecked()
+}

tests/codegen/issues/issue-118306.rs

@@ -0,0 +1,20 @@
+//@ compile-flags: -O -Zno-jump-tables
+//@ min-llvm-version: 19
+
+// Test for #118306.
+// Ensure that the default branch is optimized to be unreachable.
+
+#![crate_type = "lib"]
+
+#[no_mangle]
+pub fn foo(input: u64) -> u64 {
+    // CHECK-LABEL: @foo(
+    // CHECK: switch {{.*}}, label %[[UNREACHABLE:.*]] [
+    // CHECK: [[UNREACHABLE]]:
+    // CHECK-NEXT: unreachable
+    match input % 4 {
+        1 | 2 => 1,
+        3 => 2,
+        _ => 0,
+    }
+}

tests/codegen/issues/issue-126585.rs

@@ -0,0 +1,23 @@
+//@ compile-flags: -Copt-level=s
+//@ min-llvm-version: 19
+
+// Test for #126585.
+// Ensure that this IR doesn't have extra undef phi input, which also guarantees that this asm
+// doesn't have subsequent labels and unnecessary `jmp` instructions.
+
+#![crate_type = "lib"]
+
+#[no_mangle]
+fn checked_div_round(a: u64, b: u64) -> Option<u64> {
+    // CHECK-LABEL: @checked_div_round
+    // CHECK: phi
+    // CHECK-NOT: undef
+    // CHECK: phi
+    // CHECK-NOT: undef
+    match b {
+        0 => None,
+        1 => Some(a),
+        // `a / b` is computable and `(a % b) * 2` can not overflow since `b >= 2`.
+        b => Some(a / b + if (a % b) * 2 >= b { 1 } else { 0 }),
+    }
+}

tests/run-make/min-global-align/Makefile

@@ -0,0 +1,27 @@
+// This test checks that global variables respect the target minimum alignment.
+// The three bools `STATIC_BOOL`, `STATIC_MUT_BOOL`, and `CONST_BOOL` all have
+// type-alignment of 1, but some targets require greater global alignment.
+// See https://github.com/rust-lang/rust/pull/44440
+
+//@ only-linux
+// Reason: this test is target-independent, considering compilation is targeted
+// towards linux architectures only.
+
+use run_make_support::{assert_count_is, llvm_components_contain, rfs, rustc};
+
+fn main() {
+    // Most targets are happy with default alignment -- take i686 for example.
+    if llvm_components_contain("x86") {
+        rustc().target("i686-unknown-linux-gnu").emit("llvm-ir").input("min_global_align.rs").run();
+        assert_count_is(3, rfs::read_to_string("min_global_align.ll"), "align 1");
+    }
+    // SystemZ requires even alignment for PC-relative addressing.
+    if llvm_components_contain("systemz") {
+        rustc()
+            .target("s390x-unknown-linux-gnu")
+            .emit("llvm-ir")
+            .input("min_global_align.rs")
+            .run();
+        assert_count_is(3, rfs::read_to_string("min_global_align.ll"), "align 2");
+    }
+}

tests/run-make/min-global-align/rmake.rs

@@ -0,0 +1,43 @@
+#ifndef __BAR_H
+#define __BAR_H
+
+#include <sys/mman.h>
+#include <sys/auxv.h>
+#include <sys/prctl.h>
+#include <unistd.h>
+#include <stdio.h>
+
+// Set the allocation tag on the destination address using the STG instruction.
+#define set_tag(tagged_addr) do {                                      \
+    asm volatile("stg %0, [%0]" : : "r" (tagged_addr) : "memory"); \
+} while (0)
+
+int mte_enabled() {
+    return (getauxval(AT_HWCAP2)) & HWCAP2_MTE;
+}
+
+void *alloc_page() {
+    // Enable MTE with synchronous checking
+    if (prctl(PR_SET_TAGGED_ADDR_CTRL,
+              PR_TAGGED_ADDR_ENABLE | PR_MTE_TCF_SYNC | (0xfffe << PR_MTE_TAG_SHIFT),
+              0, 0, 0))
+    {
+        perror("prctl() failed");
+    }
+
+    // Using `mmap` allows us to ensure that, on systems which support MTE, the allocated
+    // memory is 16-byte aligned for MTE.
+    // This also allows us to explicitly specify whether the region should be protected by
+    // MTE or not.
+    if (mte_enabled()) {
+        void *ptr = mmap(NULL, sysconf(_SC_PAGESIZE),
+                         PROT_READ | PROT_WRITE | PROT_MTE, MAP_PRIVATE | MAP_ANONYMOUS,
+                         -1, 0);
+    } else {
+        void *ptr = mmap(NULL, sysconf(_SC_PAGESIZE),
+                         PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS,
+                         -1, 0);
+    }
+}
+
+#endif // __BAR_H

tests/run-make/mte-ffi/bar.h

@@ -0,0 +1,44 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include "bar.h"
+
+extern void foo(char*);
+
+void bar(char *ptr) {
+    if (((uintptr_t)ptr >> 56) != 0x1f) {
+        fprintf(stderr, "Top byte corrupted on Rust -> C FFI boundary!\n");
+        exit(1);
+    }
+}
+
+int main(void)
+{
+    float *ptr = alloc_page();
+    if (ptr == MAP_FAILED)
+    {
+        perror("mmap() failed");
+        return EXIT_FAILURE;
+    }
+
+    // Store an arbitrary tag in bits 56-59 of the pointer (where an MTE tag may be),
+    // and a different value in the ignored top 4 bits.
+    ptr = (float *)((uintptr_t)ptr | 0x1fl << 56);
+
+    if (mte_enabled()) {
+        set_tag(ptr);
+    }
+
+    ptr[0] = 2.0f;
+    ptr[1] = 1.5f;
+
+    foo(ptr); // should change the contents of the page and call `bar`
+
+    if (ptr[0] != 0.5f || ptr[1] != 0.2f) {
+        fprintf(stderr, "invalid data in memory; expected '0.5 0.2', got '%f %f'\n",
+                ptr[0], ptr[1]);
+        return EXIT_FAILURE;
+    }
+
+    return 0;
+}

tests/run-make/mte-ffi/bar_float.c

@@ -0,0 +1,39 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include "bar.h"
+
+typedef void (*fp)(int (*)());
+
+extern void foo(fp);
+
+void bar(int (*ptr)()) {
+    if (((uintptr_t)ptr >> 56) != 0x2f) {
+        fprintf(stderr, "Top byte corrupted on Rust -> C FFI boundary!\n");
+        exit(1);
+    }
+
+    int r = (*ptr)();
+    if (r != 32) {
+        fprintf(stderr, "invalid return value; expected 32, got '%d'\n", r);
+        exit(1);
+    }
+}
+
+int main(void)
+{
+    fp ptr = alloc_page();
+    if (ptr == MAP_FAILED)
+    {
+        perror("mmap() failed");
+        return EXIT_FAILURE;
+    }
+
+    // Store an arbitrary tag in bits 56-59 of the pointer (where an MTE tag may be),
+    // and a different value in the ignored top 4 bits.
+    ptr = (fp)((uintptr_t)&bar | 0x1fl << 56);
+
+    foo(ptr);
+
+    return 0;
+}

tests/run-make/mte-ffi/bar_function.c

@@ -0,0 +1,47 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include "bar.h"
+
+extern void foo(unsigned int *);
+
+void bar(char *ptr) {
+    if (((uintptr_t)ptr >> 56) != 0x1f) {
+        fprintf(stderr, "Top byte corrupted on Rust -> C FFI boundary!\n");
+        exit(1);
+    }
+}
+
+int main(void)
+{
+    // Construct a pointer with an arbitrary tag in bits 56-59, simulating an MTE tag.
+    // It's only necessary that the tag is preserved across FFI bounds for this test.
+    unsigned int *ptr;
+
+    ptr = alloc_page();
+    if (ptr == MAP_FAILED)
+    {
+        perror("mmap() failed");
+        return EXIT_FAILURE;
+    }
+
+    // Store an arbitrary tag in bits 56-59 of the pointer (where an MTE tag may be),
+    // and a different value in the ignored top 4 bits.
+    ptr = (unsigned int *)((uintptr_t)ptr | 0x1fl << 56);
+
+    if (mte_enabled()) {
+        set_tag(ptr);
+    }
+
+    ptr[0] = 61;
+    ptr[1] = 62;
+
+    foo(ptr); // should change the contents of the page to start with 0x63 0x64 and call `bar`
+
+    if (ptr[0] != 0x63 || ptr[1] != 0x64) {
+        fprintf(stderr, "invalid data in memory; expected '63 64', got '%d %d'\n", ptr[0], ptr[1]);
+        return EXIT_FAILURE;
+    }
+
+    return 0;
+}