RPCS3/llvm-mirror
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-23 03:02:36 +01:00
Code Issues Projects Releases Wiki Activity

[CGDebugInfo] Emit subprograms for decls when AT_tail_call is understood

Browse Source 
Currently, clang emits subprograms for declared functions when the
target debugger or DWARF standard is known to support entry values
(DW_OP_entry_value & the GNU equivalent).

Treat DW_AT_tail_call the same way to allow debuggers to follow cross-TU
tail calls.

Pre-patch debug session with a cross-TU tail call:

```
  * frame #0: 0x0000000100000fa4 main`target at b.c:4:3 [opt]
    frame #1: 0x0000000100000f99 main`main at a.c:8:10 [opt]
```

Post-patch (note that the tail-calling frame, "helper", is visible):

```
  * frame #0: 0x0000000100000fa4 main`target at b.c:4:3 [opt]
    frame #1: 0x0000000100000f80 main`helper [opt] [artificial]
    frame #2: 0x0000000100000f99 main`main at a.c:8:10 [opt]
```

rdar://46577651

Differential Revision: https://reviews.llvm.org/D69743
This commit is contained in:
Vedant Kumar 2019-11-01 17:20:38 -07:00
parent 912bf78b87
commit 73d1a7c36c
1 changed files with 9 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
test/DebugInfo/X86/dwarf-callsite-related-attrs.ll
View File

@ -25,6 +25,14 @@
@sink = global i32 0, align 4, !dbg !0
define void @__has_no_subprogram() {
entry:
%0 = load volatile i32, i32* @sink, align 4
%inc = add nsw i32 %0, 1
store volatile i32 %inc, i32* @sink, align 4
ret void
}
; ASM: DW_TAG_subprogram
; ASM: DW_AT_call_all_calls
; OBJ: [[bat_sp:.*]]: DW_TAG_subprogram
@ -70,6 +78,7 @@ entry:
; OBJ: DW_AT_call_tail_call
define void @_Z3foov() !dbg !25 {
entry:
tail call void @__has_no_subprogram()
tail call void @_Z3barv(), !dbg !26
tail call void @_Z3batv(), !dbg !27
tail call void @_Z3barv(), !dbg !26