Rollup merge of rust-lang#111618 - cjgillot:name-return-place, r=tmiasko

Always name the return place.

MIR opts more and more consider `_0` as just another local, so there is no point in keeping the special case in debug-info logic.

Author: matthiaskrgr

compiler/rustc_codegen_ssa/src/mir/debuginfo.rs

@@ -328,8 +328,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
 
         let local_ref = &self.locals[local];
 
-        // FIXME Should the return place be named?
-        let name = if bx.sess().fewer_names() || local == mir::RETURN_PLACE {
+        let name = if bx.sess().fewer_names() {
             None
         } else {
             Some(match whole_local_var.or(fallback_var.clone()) {

tests/codegen/array-codegen.rs

@@ -6,10 +6,10 @@
 // CHECK-LABEL: @array_load
 #[no_mangle]
 pub fn array_load(a: &[u8; 4]) -> [u8; 4] {
-    // CHECK: %0 = alloca [4 x i8], align 1
+    // CHECK: %_0 = alloca [4 x i8], align 1
     // CHECK: %[[TEMP1:.+]] = load <4 x i8>, ptr %a, align 1
-    // CHECK: store <4 x i8> %[[TEMP1]], ptr %0, align 1
-    // CHECK: %[[TEMP2:.+]] = load i32, ptr %0, align 1
+    // CHECK: store <4 x i8> %[[TEMP1]], ptr %_0, align 1
+    // CHECK: %[[TEMP2:.+]] = load i32, ptr %_0, align 1
     // CHECK: ret i32 %[[TEMP2]]
     *a
 }

tests/codegen/avr/avr-func-addrspace.rs

@@ -116,7 +116,7 @@ pub enum Either<T, U> { A(T), B(U) }
 // with the `ptr` field representing both `&i32` and `fn()` depending on the variant.
 // This is incorrect, because `fn()` should be `ptr addrspace(1)`, not `ptr`.
 
-// CHECK: define{{.+}}void @should_not_combine_addrspace({{.+\*|ptr}}{{.+}}sret{{.+}}%0, {{.+\*|ptr}}{{.+}}%x)
+// CHECK: define{{.+}}void @should_not_combine_addrspace({{.+\*|ptr}}{{.+}}sret{{.+}}%_0, {{.+\*|ptr}}{{.+}}%x)
 #[no_mangle]
 #[inline(never)]
 pub fn should_not_combine_addrspace(x: Either<&i32, fn()>) -> Either<&i32, fn()> {

tests/codegen/consts.rs

@@ -1,4 +1,5 @@
 // compile-flags: -C no-prepopulate-passes
+// min-llvm-version: 15.0 (for opaque pointers)
 
 #![crate_type = "lib"]
 
@@ -42,14 +43,14 @@ pub fn inline_enum_const() -> E<i8, i16> {
 #[no_mangle]
 pub fn low_align_const() -> E<i16, [i16; 3]> {
     // Check that low_align_const and high_align_const use the same constant
-    // CHECK: memcpy.{{.+}}({{i8\*|ptr}} align 2 %{{[0-9]+}}, {{i8\*|ptr}} align 2 {{.*}}[[LOW_HIGH]]{{.*}}, i{{(32|64)}} 8, i1 false)
+    // CHECK: memcpy.{{.+}}(ptr align 2 %_0, ptr align 2 {{.*}}[[LOW_HIGH]]{{.*}}, i{{(32|64)}} 8, i1 false)
     *&E::A(0)
 }
 
 // CHECK-LABEL: @high_align_const
 #[no_mangle]
 pub fn high_align_const() -> E<i16, i32> {
     // Check that low_align_const and high_align_const use the same constant
-    // CHECK: memcpy.{{.+}}({{i8\*|ptr}} align 4 %{{[0-9]+}}, {{i8\*|ptr}} align 4 {{.*}}[[LOW_HIGH]]{{.*}}, i{{(32|64)}} 8, i1 false)
+    // CHECK: memcpy.{{.+}}(ptr align 4 %_0, ptr align 4 {{.*}}[[LOW_HIGH]]{{.*}}, i{{(32|64)}} 8, i1 false)
     *&E::A(0)
 }

tests/codegen/enum-match.rs

@@ -15,7 +15,7 @@ pub enum Enum0 {
 // CHECK-NEXT: start:
 // CHECK-NEXT: %1 = icmp eq i8 %0, 2
 // CHECK-NEXT: %2 = and i8 %0, 1
-// CHECK-NEXT: %.0 = select i1 %1, i8 13, i8 %2
+// CHECK-NEXT: %_0.0 = select i1 %1, i8 13, i8 %2
 #[no_mangle]
 pub fn match0(e: Enum0) -> u8 {
     use Enum0::*;

tests/codegen/fewer-names.rs

@@ -13,8 +13,8 @@ pub fn sum(x: u32, y: u32) -> u32 {
 
     // NO-LABEL: define{{.*}}i32 @sum(i32 noundef %x, i32 noundef %y)
     // NO-NEXT:  start:
-    // NO-NEXT:    %0 = add i32 %y, %x
-    // NO-NEXT:    ret i32 %0
+    // NO-NEXT:    %z = add i32 %y, %x
+    // NO-NEXT:    ret i32 %z
     let z = x + y;
     z
 }

tests/codegen/function-arguments-noopt.rs

@@ -42,7 +42,7 @@ pub fn borrow_call(x: &i32, f: fn(&i32) -> &i32) -> &i32 {
   f(x)
 }
 
-// CHECK: void @struct_({{%S\*|ptr}} sret(%S){{( %0)?}}, {{%S\*|ptr}} %x)
+// CHECK: void @struct_({{%S\*|ptr}} sret(%S){{( %_0)?}}, {{%S\*|ptr}} %x)
 #[no_mangle]
 pub fn struct_(x: S) -> S {
   x
@@ -51,7 +51,7 @@ pub fn struct_(x: S) -> S {
 // CHECK-LABEL: @struct_call
 #[no_mangle]
 pub fn struct_call(x: S, f: fn(S) -> S) -> S {
-  // CHECK: call void %f({{%S\*|ptr}} sret(%S){{( %0)?}}, {{%S\*|ptr}} %{{.+}})
+  // CHECK: call void %f({{%S\*|ptr}} sret(%S){{( %_0)?}}, {{%S\*|ptr}} %{{.+}})
   f(x)
 }
 

tests/codegen/function-arguments.rs

@@ -188,7 +188,7 @@ pub fn notunpin_box(x: Box<NotUnpin>) -> Box<NotUnpin> {
   x
 }
 
-// CHECK: @struct_return({{%S\*|ptr}} noalias nocapture noundef sret(%S) dereferenceable(32){{( %0)?}})
+// CHECK: @struct_return({{%S\*|ptr}} noalias nocapture noundef sret(%S) dereferenceable(32){{( %_0)?}})
 #[no_mangle]
 pub fn struct_return() -> S {
   S {

tests/codegen/intrinsics/transmute-niched.rs

@@ -169,16 +169,16 @@ pub unsafe fn check_bool_from_ordering(x: std::cmp::Ordering) -> bool {
 // CHECK-LABEL: @check_bool_to_ordering(
 #[no_mangle]
 pub unsafe fn check_bool_to_ordering(x: bool) -> std::cmp::Ordering {
-    // CHECK: %0 = zext i1 %x to i8
-    // OPT: %1 = icmp ule i8 %0, 1
-    // OPT: call void @llvm.assume(i1 %1)
-    // OPT: %2 = icmp uge i8 %0, -1
-    // OPT: %3 = icmp ule i8 %0, 1
-    // OPT: %4 = or i1 %2, %3
-    // OPT: call void @llvm.assume(i1 %4)
+    // CHECK: %_0 = zext i1 %x to i8
+    // OPT: %0 = icmp ule i8 %_0, 1
+    // OPT: call void @llvm.assume(i1 %0)
+    // OPT: %1 = icmp uge i8 %_0, -1
+    // OPT: %2 = icmp ule i8 %_0, 1
+    // OPT: %3 = or i1 %1, %2
+    // OPT: call void @llvm.assume(i1 %3)
     // DBG-NOT: icmp
     // DBG-NOT: assume
-    // CHECK: ret i8 %0
+    // CHECK: ret i8 %_0
 
     transmute(x)
 }

tests/codegen/intrinsics/transmute-x64.rs

@@ -11,25 +11,25 @@ use std::mem::transmute;
 #[no_mangle]
 pub unsafe fn check_sse_float_to_int(x: __m128) -> __m128i {
     // CHECK-NOT: alloca
-    // CHECK: %1 = load <4 x float>, ptr %x, align 16
-    // CHECK: store <4 x float> %1, ptr %0, align 16
+    // CHECK: %0 = load <4 x float>, ptr %x, align 16
+    // CHECK: store <4 x float> %0, ptr %_0, align 16
     transmute(x)
 }
 
 // CHECK-LABEL: @check_sse_pair_to_avx(
 #[no_mangle]
 pub unsafe fn check_sse_pair_to_avx(x: (__m128i, __m128i)) -> __m256i {
     // CHECK-NOT: alloca
-    // CHECK: %1 = load <4 x i64>, ptr %x, align 16
-    // CHECK: store <4 x i64> %1, ptr %0, align 32
+    // CHECK: %0 = load <4 x i64>, ptr %x, align 16
+    // CHECK: store <4 x i64> %0, ptr %_0, align 32
     transmute(x)
 }
 
 // CHECK-LABEL: @check_sse_pair_from_avx(
 #[no_mangle]
 pub unsafe fn check_sse_pair_from_avx(x: __m256i) -> (__m128i, __m128i) {
     // CHECK-NOT: alloca
-    // CHECK: %1 = load <4 x i64>, ptr %x, align 32
-    // CHECK: store <4 x i64> %1, ptr %0, align 16
+    // CHECK: %0 = load <4 x i64>, ptr %x, align 32
+    // CHECK: store <4 x i64> %0, ptr %_0, align 16
     transmute(x)
 }