From 04ff1444bb89379d7489bda9edc65ebaae4db037 Mon Sep 17 00:00:00 2001 From: winstonallo Date: Wed, 13 Aug 2025 08:51:58 +0200 Subject: Set NumRegisterParameters LLVM module flag to `N` when `-Zregparm=N` is set * Enforce the `-Zregparm=N` flag by setting the NumRegisterParameters LLVM module flag * Add assembly tests verifying that the parameters are passed in registers for reparm values 1, 2, and 3, for both LLVM intrinsics and non-builtin functions * Add c_void type to minicore --- compiler/rustc_codegen_llvm/src/context.rs | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'compiler/rustc_codegen_llvm/src/context.rs') diff --git a/compiler/rustc_codegen_llvm/src/context.rs b/compiler/rustc_codegen_llvm/src/context.rs index ee77774c688..215508f8095 100644 --- a/compiler/rustc_codegen_llvm/src/context.rs +++ b/compiler/rustc_codegen_llvm/src/context.rs @@ -372,6 +372,15 @@ pub(crate) unsafe fn create_module<'ll>( } } + if let Some(regparm_count) = sess.opts.unstable_opts.regparm { + llvm::add_module_flag_u32( + llmod, + llvm::ModuleFlagMergeBehavior::Error, + "NumRegisterParameters", + regparm_count, + ); + } + if let Some(BranchProtection { bti, pac_ret }) = sess.opts.unstable_opts.branch_protection { if sess.target.arch == "aarch64" { llvm::add_module_flag_u32( -- cgit 1.4.1-3-g733a5 From 1cd7080c3a7f29297675a72a157575ae12717304 Mon Sep 17 00:00:00 2001 From: Alice Ryhl Date: Wed, 7 May 2025 07:57:01 +0000 Subject: Add -Zindirect-branch-cs-prefix (from draft PR) --- compiler/rustc_codegen_llvm/src/context.rs | 9 +++++++++ compiler/rustc_interface/src/tests.rs | 1 + compiler/rustc_session/src/options.rs | 2 ++ tests/codegen-llvm/indirect-branch-cs-prefix.rs | 18 ++++++++++++++++++ 4 files changed, 30 insertions(+) create mode 100644 tests/codegen-llvm/indirect-branch-cs-prefix.rs (limited to 'compiler/rustc_codegen_llvm/src/context.rs') diff --git a/compiler/rustc_codegen_llvm/src/context.rs b/compiler/rustc_codegen_llvm/src/context.rs index b0f3494ea68..ea3a21dfdb5 100644 --- a/compiler/rustc_codegen_llvm/src/context.rs +++ b/compiler/rustc_codegen_llvm/src/context.rs @@ -462,6 +462,15 @@ pub(crate) unsafe fn create_module<'ll>( } } + if sess.opts.unstable_opts.indirect_branch_cs_prefix { + llvm::add_module_flag_u32( + llmod, + llvm::ModuleFlagMergeBehavior::Override, + "indirect_branch_cs_prefix", + 1, + ); + } + match (sess.opts.unstable_opts.small_data_threshold, sess.target.small_data_threshold_support()) { // Set up the small-data optimization limit for architectures that use diff --git a/compiler/rustc_interface/src/tests.rs b/compiler/rustc_interface/src/tests.rs index 0a764808f95..4425877308a 100644 --- a/compiler/rustc_interface/src/tests.rs +++ b/compiler/rustc_interface/src/tests.rs @@ -807,6 +807,7 @@ fn test_unstable_options_tracking_hash() { tracked!(hint_mostly_unused, true); tracked!(human_readable_cgu_names, true); tracked!(incremental_ignore_spans, true); + tracked!(indirect_branch_cs_prefix, true); tracked!(inline_mir, Some(true)); tracked!(inline_mir_hint_threshold, Some(123)); tracked!(inline_mir_threshold, Some(123)); diff --git a/compiler/rustc_session/src/options.rs b/compiler/rustc_session/src/options.rs index 0e112edc733..fce4d18a1d8 100644 --- a/compiler/rustc_session/src/options.rs +++ b/compiler/rustc_session/src/options.rs @@ -2295,6 +2295,8 @@ options! { - hashes of green query instances - hash collisions of query keys - hash collisions when creating dep-nodes"), + indirect_branch_cs_prefix: bool = (false, parse_bool, [TRACKED TARGET_MODIFIER], + "add cs prefix to call and jmp to indirect thunk (default: no)"), inline_llvm: bool = (true, parse_bool, [TRACKED], "enable LLVM inlining (default: yes)"), inline_mir: Option = (None, parse_opt_bool, [TRACKED], diff --git a/tests/codegen-llvm/indirect-branch-cs-prefix.rs b/tests/codegen-llvm/indirect-branch-cs-prefix.rs new file mode 100644 index 00000000000..a00b63a4970 --- /dev/null +++ b/tests/codegen-llvm/indirect-branch-cs-prefix.rs @@ -0,0 +1,18 @@ +// Test that the `indirect_branch_cs_prefix` module attribute is (not) emitted when the +// `-Zindirect-branch-cs-prefix` flag is (not) set. + +//@ add-core-stubs +//@ revisions: unset set +//@ needs-llvm-components: x86 +//@ compile-flags: --target x86_64-unknown-linux-gnu +//@ [set] compile-flags: -Zindirect-branch-cs-prefix + +#![crate_type = "lib"] +#![feature(no_core, lang_items)] +#![no_core] + +#[lang = "sized"] +trait Sized {} + +// unset-NOT: !{{[0-9]+}} = !{i32 4, !"indirect_branch_cs_prefix", i32 1} +// set: !{{[0-9]+}} = !{i32 4, !"indirect_branch_cs_prefix", i32 1} -- cgit 1.4.1-3-g733a5