From c2102259a04dd9ede1e7faf01daa0dfcb948c214 Mon Sep 17 00:00:00 2001
From: Bastian Kersting <bkersting@google.com>
Date: Fri, 8 Nov 2024 08:51:19 +0000
Subject: [PATCH] CFI: Append debug location to CFI blocks
---
compiler/rustc_codegen_gcc/src/debuginfo.rs | 4 ++++
compiler/rustc_codegen_llvm/src/builder.rs | 7 +++++++
.../rustc_codegen_llvm/src/debuginfo/mod.rs | 4 ++++
compiler/rustc_codegen_llvm/src/llvm/ffi.rs | 1 +
.../rustc_codegen_ssa/src/traits/debuginfo.rs | 1 +
.../cfi/dbg-location-on-cfi-blocks.rs | 19 +++++++++++++++++++
6 files changed, 36 insertions(+)
create mode 100644 tests/codegen/sanitizer/cfi/dbg-location-on-cfi-blocks.rs
diff --git a/compiler/rustc_codegen_gcc/src/debuginfo.rs b/compiler/rustc_codegen_gcc/src/debuginfo.rs
index 9d62ccc95d56d..5d8c5c199b12c 100644
--- a/compiler/rustc_codegen_gcc/src/debuginfo.rs
+++ b/compiler/rustc_codegen_gcc/src/debuginfo.rs
@@ -52,6 +52,10 @@ impl<'a, 'gcc, 'tcx> DebugInfoBuilderMethods for Builder<'a, 'gcc, 'tcx> {
fn clear_dbg_loc(&mut self) {
self.location = None;
}
+
+ fn get_dbg_loc(&self) -> Option<Self::DILocation> {
+ self.location
+ }
}
/// Generate the `debug_context` in an MIR Body.
diff --git a/compiler/rustc_codegen_llvm/src/builder.rs b/compiler/rustc_codegen_llvm/src/builder.rs
index 751b2235dc856..ac76b781218af 100644
--- a/compiler/rustc_codegen_llvm/src/builder.rs
+++ b/compiler/rustc_codegen_llvm/src/builder.rs
@@ -1574,6 +1574,7 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> {
cfi::typeid_for_fnabi(self.tcx, fn_abi, options)
};
let typeid_metadata = self.cx.typeid_metadata(typeid).unwrap();
+ let dbg_loc = self.get_dbg_loc();
// Test whether the function pointer is associated with the type identifier.
let cond = self.type_test(llfn, typeid_metadata);
@@ -1582,10 +1583,16 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> {
self.cond_br(cond, bb_pass, bb_fail);
self.switch_to_block(bb_fail);
+ if let Some(dbg_loc) = dbg_loc {
+ self.set_dbg_loc(dbg_loc);
+ }
self.abort();
self.unreachable();
self.switch_to_block(bb_pass);
+ if let Some(dbg_loc) = dbg_loc {
+ self.set_dbg_loc(dbg_loc);
+ }
}
}
diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
index 9e1e5127e80f3..89492e4b9fe58 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
@@ -206,6 +206,10 @@ impl<'ll> DebugInfoBuilderMethods for Builder<'_, 'll, '_> {
}
}
+ fn get_dbg_loc(&self) -> Option<&'ll DILocation> {
+ unsafe { llvm::LLVMGetCurrentDebugLocation2(self.llbuilder) }
+ }
+
fn insert_reference_to_gdb_debug_scripts_section_global(&mut self) {
gdb::insert_reference_to_gdb_debug_scripts_section_global(self)
}
diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
index d84ae8d8836b9..9ea1f4698138c 100644
--- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
@@ -1063,6 +1063,7 @@ unsafe extern "C" {
// Metadata
pub fn LLVMSetCurrentDebugLocation2<'a>(Builder: &Builder<'a>, Loc: *const Metadata);
+ pub fn LLVMGetCurrentDebugLocation2<'a>(Builder: &Builder<'a>) -> Option<&'a Metadata>;
// Terminators
pub fn LLVMBuildRetVoid<'a>(B: &Builder<'a>) -> &'a Value;
diff --git a/compiler/rustc_codegen_ssa/src/traits/debuginfo.rs b/compiler/rustc_codegen_ssa/src/traits/debuginfo.rs
index 670433a6c3308..fe135e911fb3f 100644
--- a/compiler/rustc_codegen_ssa/src/traits/debuginfo.rs
+++ b/compiler/rustc_codegen_ssa/src/traits/debuginfo.rs
@@ -81,6 +81,7 @@ pub trait DebugInfoBuilderMethods: BackendTypes {
);
fn set_dbg_loc(&mut self, dbg_loc: Self::DILocation);
fn clear_dbg_loc(&mut self);
+ fn get_dbg_loc(&self) -> Option<Self::DILocation>;
fn insert_reference_to_gdb_debug_scripts_section_global(&mut self);
fn set_var_name(&mut self, value: Self::Value, name: &str);
}
diff --git a/tests/codegen/sanitizer/cfi/dbg-location-on-cfi-blocks.rs b/tests/codegen/sanitizer/cfi/dbg-location-on-cfi-blocks.rs
new file mode 100644
index 0000000000000..df65960dfe0be
--- /dev/null
+++ b/tests/codegen/sanitizer/cfi/dbg-location-on-cfi-blocks.rs
@@ -0,0 +1,19 @@
+// Verifies that the parent block's debug information are assigned to the inserted cfi block.
+//
+//@ needs-sanitizer-cfi
+//@ compile-flags: -Clto -Cno-prepopulate-passes -Copt-level=0 -Zsanitizer=cfi -Ctarget-feature=-crt-static -Cdebuginfo=1
+
+#![crate_type = "lib"]
+
+pub fn foo(f: fn(i32) -> i32, arg: i32) -> i32 {
+ // CHECK-LABEL: define{{.*}}foo{{.*}}!dbg !{{[0-9]+}} !type !{{[0-9]+}} !type !{{[0-9]+}} !type !{{[0-9]+}} !type !{{[0-9]+}}
+ // CHECK: start:
+ // CHECK: [[TT:%.+]] = call i1 @llvm.type.test(ptr {{%f|%0}}, metadata !"{{[[:print:]]+}}"), !dbg !{{[0-9]+}}
+ // CHECK-NEXT: br i1 [[TT]], label %type_test.pass, label %type_test.fail, !dbg !{{[0-9]+}}
+ // CHECK: type_test.pass: ; preds = %start
+ // CHECK-NEXT: {{%.+}} = call i32 %f(i32{{.*}} %arg), !dbg !{{[0-9]+}}
+ // CHECK: type_test.fail: ; preds = %start
+ // CHECK-NEXT: call void @llvm.trap(), !dbg !{{[0-9]+}}
+ // CHECK-NEXT: unreachable, !dbg !{{[0-9]+}}
+ f(arg)
+}