Rollup merge of #132702 - 1c3t3a:issue-132615, r=rcvalle

CFI: Append debug location to CFI blocks

Currently we're not appending debug locations to the inserted CFI blocks. This shows up in #132615 and #100783. This change fixes that by passing down the debug location to the CFI type-test generation and appending it to the blocks.

Credits also belong to `@jakos-sec` who worked with me on this.

3 files changed, 12 insertions, 0 deletions

diff --git a/compiler/rustc_codegen_llvm/src/builder.rs b/compiler/rustc_codegen_llvm/src/builder.rs
index 751b2235dc8..ac76b781218 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 9e1e5127e80..89492e4b9fe 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 75a5ec44c22..7f59264824e 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;