rustc_codegen_llvm: give names to non-alloca variable values.

3 files changed, 24 insertions, 10 deletions

diff --git a/src/librustc_codegen_ssa/mir/mod.rs b/src/librustc_codegen_ssa/mir/mod.rs
index 8acb3ba0626..00e9ca01f4d 100644
--- a/src/librustc_codegen_ssa/mir/mod.rs
+++ b/src/librustc_codegen_ssa/mir/mod.rs
@@ -518,19 +518,19 @@ fn arg_local_refs<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
                 PassMode::Ignore(IgnoreMode::CVarArgs) => {}
                 PassMode::Direct(_) => {
                     let llarg = bx.get_param(llarg_idx);
-                    bx.set_value_name(llarg, &name);
+                    bx.set_var_name(llarg, &name);
                     llarg_idx += 1;
                     return local(
                         OperandRef::from_immediate_or_packed_pair(bx, llarg, arg.layout));
                 }
                 PassMode::Pair(..) => {
-                    let a = bx.get_param(llarg_idx);
-                    bx.set_value_name(a, &(name.clone() + ".0"));
-                    llarg_idx += 1;
+                    let (a, b) = (bx.get_param(llarg_idx), bx.get_param(llarg_idx + 1));
+                    llarg_idx += 2;
 
-                    let b = bx.get_param(llarg_idx);
-                    bx.set_value_name(b, &(name + ".1"));
-                    llarg_idx += 1;
+                    // FIXME(eddyb) these are scalar components,
+                    // maybe extract the high-level fields?
+                    bx.set_var_name(a, format_args!("{}.0", name));
+                    bx.set_var_name(b, format_args!("{}.1", name));
 
                     return local(OperandRef {
                         val: OperandValue::Pair(a, b),
@@ -546,7 +546,7 @@ fn arg_local_refs<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
             // already put it in a temporary alloca and gave it up.
             // FIXME: lifetimes
             let llarg = bx.get_param(llarg_idx);
-            bx.set_value_name(llarg, &name);
+            bx.set_var_name(llarg, &name);
             llarg_idx += 1;
             PlaceRef::new_sized(llarg, arg.layout)
         } else if arg.is_unsized_indirect() {
diff --git a/src/librustc_codegen_ssa/mir/statement.rs b/src/librustc_codegen_ssa/mir/statement.rs
index 3617f3afaae..594f45c8337 100644
--- a/src/librustc_codegen_ssa/mir/statement.rs
+++ b/src/librustc_codegen_ssa/mir/statement.rs
@@ -29,7 +29,21 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                             self.codegen_rvalue_unsized(bx, cg_indirect_dest, rvalue)
                         }
                         LocalRef::Operand(None) => {
-                            let (bx, operand) = self.codegen_rvalue_operand(bx, rvalue);
+                            let (mut bx, operand) = self.codegen_rvalue_operand(bx, rvalue);
+                            if let Some(name) = self.mir.local_decls[index].name {
+                                match operand.val {
+                                    OperandValue::Ref(x, ..) |
+                                    OperandValue::Immediate(x) => {
+                                        bx.set_var_name(x, name);
+                                    }
+                                    OperandValue::Pair(a, b) => {
+                                        // FIXME(eddyb) these are scalar components,
+                                        // maybe extract the high-level fields?
+                                        bx.set_var_name(a, format_args!("{}.0", name));
+                                        bx.set_var_name(b, format_args!("{}.1", name));
+                                    }
+                                }
+                            }
                             self.locals[index] = LocalRef::Operand(Some(operand));
                             bx
                         }
diff --git a/src/librustc_codegen_ssa/traits/debuginfo.rs b/src/librustc_codegen_ssa/traits/debuginfo.rs
index be2fa7279aa..9c16b864ef2 100644
--- a/src/librustc_codegen_ssa/traits/debuginfo.rs
+++ b/src/librustc_codegen_ssa/traits/debuginfo.rs
@@ -57,5 +57,5 @@ pub trait DebugInfoBuilderMethods<'tcx>: BackendTypes {
         span: Span,
     );
     fn insert_reference_to_gdb_debug_scripts_section_global(&mut self);
-    fn set_value_name(&mut self, value: Self::Value, name: &str);
+    fn set_var_name(&mut self, value: Self::Value, name: impl ToString);
 }