Emit the correct flags for the PROC CodeView Debug Symbol

The S_LPROC32_ID and S_GPROC32_ID CodeView Debug Symbols have a flags
field which LLVM has had the values for (in the ProcSymFlags enum) but
has never actually set.

These flags are used by Microsoft-internal tooling that leverages debug
information to do binary analysis.

Modified LLVM to set the correct flags:

- ProcSymFlags::HasOptimizedDebugInfo - always set, as this indicates that
debug info is present for optimized builds (if debug info is not emitted
for optimized builds, then LLVM won't emit a debug symbol at all).
- ProcSymFlags::IsNoReturn and ProcSymFlags::IsNoInline - set if the
function has the NoReturn or NoInline attributes respectively.
- ProcSymFlags::HasFP - set if the function requires a frame pointer (per
TargetFrameLowering::hasFP).

Differential Revision: https://reviews.llvm.org/D148761

llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp

@@ -1160,7 +1160,14 @@ void CodeViewDebug::emitDebugInfoForFunction(const Function *GV,
     OS.AddComment("Function section index");
     OS.emitCOFFSectionIndex(Fn);
     OS.AddComment("Flags");
-    OS.emitInt8(0);
+    ProcSymFlags ProcFlags = ProcSymFlags::HasOptimizedDebugInfo;
+    if (FI.HasFramePointer)
+      ProcFlags |= ProcSymFlags::HasFP;
+    if (GV->hasFnAttribute(Attribute::NoReturn))
+      ProcFlags |= ProcSymFlags::IsNoReturn;
+    if (GV->hasFnAttribute(Attribute::NoInline))
+      ProcFlags |= ProcSymFlags::IsNoInline;
+    OS.emitInt8(static_cast<uint8_t>(ProcFlags));
     // Emit the function display name as a null-terminated string.
     OS.AddComment("Function name");
     // Truncate the name so we won't overflow the record length field.
@@ -1478,6 +1485,7 @@ void CodeViewDebug::beginFunctionImpl(const MachineFunction *MF) {
       CurFn->EncodedLocalFramePtrReg = EncodedFramePtrReg::StackPtr;
       CurFn->EncodedParamFramePtrReg = EncodedFramePtrReg::StackPtr;
     } else {
+      CurFn->HasFramePointer = true;
       // If there is an FP, parameters are always relative to it.
       CurFn->EncodedParamFramePtrReg = EncodedFramePtrReg::FramePtr;
       if (CurFn->HasStackRealignment) {

llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h

@@ -191,6 +191,8 @@ class LLVM_LIBRARY_VISIBILITY CodeViewDebug : public DebugHandlerBase {
     bool HasStackRealignment = false;
 
     bool HaveLineInfo = false;
+
+    bool HasFramePointer = false;
   };
   FunctionInfo *CurFn = nullptr;
 

llvm/test/DebugInfo/COFF/fpo-realign-alloca.ll

@@ -1,4 +1,5 @@
 ; RUN: llc < %s | FileCheck %s
+; RUN: llc -mtriple=i686-windows-msvc < %s -filetype=obj | llvm-readobj --codeview - | FileCheck %s --check-prefix=OBJ
 
 ; C source:
 ; void usethings(ptr, ptr p);
@@ -33,6 +34,15 @@
 ; CHECK:         retl
 ; CHECK:         .cv_fpo_endproc
 
+; OBJ-LABEL:     FunctionType: realign_and_alloca (0x1002)
+; OBJ-NEXT:      CodeOffset: _realign_and_alloca+0x0
+; OBJ-NEXT:      Segment: 0x0
+; OBJ-NEXT:      Flags [ (0x81)
+; OBJ-NEXT:        HasFP (0x1)
+; OBJ-NEXT:        HasOptimizedDebugInfo (0x80)
+; OBJ-NEXT:      ]
+; OBJ-NEXT:      DisplayName: realign_and_alloca
+; OBJ-NEXT:      LinkageName: _realign_and_alloca
 
 ; ModuleID = 't.c'
 source_filename = "t.c"

llvm/test/DebugInfo/COFF/fpo-realign-vframe.ll

@@ -95,6 +95,10 @@
 ; OBJ:   SubSectionType: Symbols (0xF1)
 ; OBJ:   GlobalProcIdSym {
 ; OBJ:     Kind: S_GPROC32_ID (0x1147)
+; OBJ:     Flags [ (0x81)
+; OBJ:       HasFP (0x1)
+; OBJ:       HasOptimizedDebugInfo (0x80)
+; OBJ:     ]
 ; OBJ:     DisplayName: realign_with_csrs
 ; OBJ:     LinkageName: _realign_with_csrs
 ; OBJ:   }

llvm/test/DebugInfo/COFF/frameproc-flags.ll

@@ -63,22 +63,27 @@
 ; }
 
 ; CHECK-LABEL: S_GPROC32_ID [size = 52] `use_alloca`
+; CHECK:   type = `0x1002 (use_alloca)`, debug start = 0, debug end = 0, flags = has fp | opt debuginfo
 ; CHECK: S_FRAMEPROC [size = 32]
 ; CHECK:   local fp reg = VFRAME, param fp reg = EBP
 ; CHECK:   flags = has alloca | secure checks | strict secure checks | opt speed
 ; CHECK-LABEL: S_GPROC32_ID [size = 52] `call_setjmp`
+; CHECK:   type = `0x1003 (call_setjmp)`, debug start = 0, debug end = 0, flags = opt debuginfo
 ; CHECK: S_FRAMEPROC [size = 32]
 ; CHECK:   local fp reg = NONE, param fp reg = NONE
 ; CHECK:   flags = has setjmp | opt speed
 ; CHECK-LABEL: S_GPROC32_ID [size = 56] `use_inlineasm`
+; CHECK:   type = `0x1006 (use_inlineasm)`, debug start = 0, debug end = 0, flags = opt debuginfo
 ; CHECK: S_FRAMEPROC [size = 32]
 ; CHECK:   local fp reg = NONE, param fp reg = NONE
 ; CHECK:   flags = has inline asm | safe buffers | opt speed
 ; CHECK-LABEL: S_GPROC32_ID [size = 48] `cpp_eh`
+; CHECK:   type = `0x1007 (cpp_eh)`, debug start = 0, debug end = 0, flags = has fp | opt debuginfo
 ; CHECK: S_FRAMEPROC [size = 32]
 ; CHECK:   local fp reg = EBP, param fp reg = EBP
 ; CHECK:   flags = has eh | opt speed
 ; CHECK-LABEL: S_GPROC32_ID [size = 52] `use_inline`
+; CHECK:   type = `0x100C (use_inline)`, debug start = 0, debug end = 0, flags = opt debuginfo
 ; CHECK: S_FRAMEPROC [size = 32]
 ; CHECK:   local fp reg = NONE, param fp reg = NONE
 ; CHECK:   flags = safe buffers | opt speed
@@ -87,6 +92,7 @@
 ; CHECK:   local fp reg = NONE, param fp reg = NONE
 ; CHECK:   flags = marked inline | safe buffers | opt speed
 ; CHECK-LABEL: S_GPROC32_ID [size = 44] `seh`
+; CHECK:   type = `0x100E (seh)`, debug start = 0, debug end = 0, flags = has fp | opt debuginfo
 ; CHECK: S_FRAMEPROC [size = 32]
 ; CHECK:   local fp reg = EBP, param fp reg = EBP
 ; CHECK:   flags = has seh | opt speed
@@ -95,10 +101,12 @@
 ; CHECK:   local fp reg = EBP, param fp reg = EBP
 ; CHECK:   flags = safe buffers | opt speed
 ; CHECK-LABEL: S_GPROC32_ID [size = 52] `use_naked`
+; CHECK:   type = `0x1010 (use_naked)`, debug start = 0, debug end = 0, flags = noinline | opt debuginfo
 ; CHECK: S_FRAMEPROC [size = 32]
 ; CHECK:   local fp reg = NONE, param fp reg = NONE
 ; CHECK:   flags = has inline asm | naked | safe buffers | opt speed
 ; CHECK-LABEL: S_GPROC32_ID [size = 52] `stack_guard`
+; CHECK:   type = `0x1011 (stack_guard)`, debug start = 0, debug end = 0, flags = opt debuginfo
 ; CHECK: S_FRAMEPROC [size = 32]
 ; CHECK:   local fp reg = VFRAME, param fp reg = VFRAME
 ; CHECK:   flags = secure checks | strict secure checks | opt speed

llvm/test/DebugInfo/COFF/function-options.ll

@@ -376,6 +376,97 @@
 ; CHECK:   }
 ; CHECK: ]
 
+; CHECK-LABEL: FunctionType: Func_AClass (0x1008)
+; CHECK-NEXT:  CodeOffset: ?Func_AClass@@YA?AVAClass@@AEAV1@@Z+0x0
+; CHECK-NEXT:  Segment: 0x0
+; CHECK-NEXT:  Flags [ (0xC0)
+; CHECK-NEXT:    HasOptimizedDebugInfo (0x80)
+; CHECK-NEXT:    IsNoInline (0x40)
+; CHECK-NEXT:  ]
+; CHECK-NEXT:  DisplayName: Func_AClass
+; CHECK-NEXT:  LinkageName: ?Func_AClass@@YA?AVAClass@@AEAV1@@Z
+; CHECK-LABEL: FunctionType: Func_BClass (0x1013)
+; CHECK-NEXT:  CodeOffset: ?Func_BClass@@YA?AVBClass@@AEAV1@@Z+0x0
+; CHECK-NEXT:  Segment: 0x0
+; CHECK-NEXT:  Flags [ (0xC0)
+; CHECK-NEXT:    HasOptimizedDebugInfo (0x80)
+; CHECK-NEXT:    IsNoInline (0x40)
+; CHECK-NEXT:  ]
+; CHECK-NEXT:  DisplayName: Func_BClass
+; CHECK-NEXT:  LinkageName: ?Func_BClass@@YA?AVBClass@@AEAV1@@Z
+; CHECK-LABEL: FunctionType: Func_C1Class (0x101D)
+; CHECK-NEXT:  CodeOffset: ?Func_C1Class@@YA?AVC1Class@@AEAV1@@Z+0x0
+; CHECK-NEXT:  Segment: 0x0
+; CHECK-NEXT:  Flags [ (0xC0)
+; CHECK-NEXT:    HasOptimizedDebugInfo (0x80)
+; CHECK-NEXT:    IsNoInline (0x40)
+; CHECK-NEXT:  ]
+; CHECK-NEXT:  DisplayName: Func_C1Class
+; CHECK-NEXT:  LinkageName: ?Func_C1Class@@YA?AVC1Class@@AEAV1@@Z
+; CHECK-LABEL: FunctionType: Func_C2Class (0x1027)
+; CHECK-NEXT:  CodeOffset: ?Func_C2Class@@YA?AVC2Class@@AEAV1@@Z+0x0
+; CHECK-NEXT:  Segment: 0x0
+; CHECK-NEXT:  Flags [ (0xC0)
+; CHECK-NEXT:    HasOptimizedDebugInfo (0x80)
+; CHECK-NEXT:    IsNoInline (0x40)
+; CHECK-NEXT:  ]
+; CHECK-NEXT:  DisplayName: Func_C2Class
+; CHECK-NEXT:  LinkageName: ?Func_C2Class@@YA?AVC2Class@@AEAV1@@Z
+; CHECK-LABEL: FunctionType: Func_DClass (0x102F)
+; CHECK-NEXT:  CodeOffset: ?Func_DClass@@YA?AVDClass@@AEAV1@@Z+0x0
+; CHECK-NEXT:  Segment: 0x0
+; CHECK-NEXT:  Flags [ (0xC0)
+; CHECK-NEXT:    HasOptimizedDebugInfo (0x80)
+; CHECK-NEXT:    IsNoInline (0x40)
+; CHECK-NEXT:  ]
+; CHECK-NEXT:  DisplayName: Func_DClass
+; CHECK-NEXT:  LinkageName: ?Func_DClass@@YA?AVDClass@@AEAV1@@Z
+; CHECK-LABEL: FunctionType: Func_FClass (0x103A)
+; CHECK-NEXT:  CodeOffset: ?Func_FClass@@YA?AVFClass@@AEAV1@@Z+0x0
+; CHECK-NEXT:  Segment: 0x0
+; CHECK-NEXT:  Flags [ (0xC0)
+; CHECK-NEXT:    HasOptimizedDebugInfo (0x80)
+; CHECK-NEXT:    IsNoInline (0x40)
+; CHECK-NEXT:  ]
+; CHECK-NEXT:  DisplayName: Func_FClass
+; CHECK-NEXT:  LinkageName: ?Func_FClass@@YA?AVFClass@@AEAV1@@Z
+; CHECK-LABEL: FunctionType: Func_AStruct (0x1041)
+; CHECK-NEXT:  CodeOffset: ?Func_AStruct@@YA?AUAStruct@@AEAU1@@Z+0x0
+; CHECK-NEXT:  Segment: 0x0
+; CHECK-NEXT:  Flags [ (0xC0)
+; CHECK-NEXT:    HasOptimizedDebugInfo (0x80)
+; CHECK-NEXT:    IsNoInline (0x40)
+; CHECK-NEXT:  ]
+; CHECK-NEXT:  DisplayName: Func_AStruct
+; CHECK-NEXT:  LinkageName: ?Func_AStruct@@YA?AUAStruct@@AEAU1@@Z
+; CHECK-LABEL: FunctionType: Func_BStruct (0x104B)
+; CHECK-NEXT:  CodeOffset: ?Func_BStruct@@YA?AUBStruct@@AEAU1@@Z+0x0
+; CHECK-NEXT:  Segment: 0x0
+; CHECK-NEXT:  Flags [ (0xC0)
+; CHECK-NEXT:    HasOptimizedDebugInfo (0x80)
+; CHECK-NEXT:    IsNoInline (0x40)
+; CHECK-NEXT:  ]
+; CHECK-NEXT:  DisplayName: Func_BStruct
+; CHECK-NEXT:  LinkageName: ?Func_BStruct@@YA?AUBStruct@@AEAU1@@Z
+; CHECK-LABEL: FunctionType: Func_AUnion (0x1052)
+; CHECK-NEXT:  CodeOffset: ?Func_AUnion@@YA?ATAUnion@@AEAT1@@Z+0x0
+; CHECK-NEXT:  Segment: 0x0
+; CHECK-NEXT:  Flags [ (0xC0)
+; CHECK-NEXT:    HasOptimizedDebugInfo (0x80)
+; CHECK-NEXT:    IsNoInline (0x40)
+; CHECK-NEXT:  ]
+; CHECK-NEXT:  DisplayName: Func_AUnion
+; CHECK-NEXT:  LinkageName: ?Func_AUnion@@YA?ATAUnion@@AEAT1@@Z
+; CHECK-LABEL: FunctionType: Func_BUnion (0x105C)
+; CHECK-NEXT:  CodeOffset: ?Func_BUnion@@YA?ATBUnion@@AEAT1@@Z+0x0
+; CHECK-NEXT:  Segment: 0x0
+; CHECK-NEXT:  Flags [ (0xC0)
+; CHECK-NEXT:    HasOptimizedDebugInfo (0x80)
+; CHECK-NEXT:    IsNoInline (0x40)
+; CHECK-NEXT:  ]
+; CHECK-NEXT:  DisplayName: Func_BUnion
+; CHECK-NEXT:  LinkageName: ?Func_BUnion@@YA?ATBUnion@@AEAT1@@Z
+
 ; ModuleID = 't.cpp'
 source_filename = "t.cpp"
 target datalayout = "e-m:w-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"

llvm/test/DebugInfo/COFF/inlining-header.ll

@@ -68,7 +68,8 @@
 ; OBJ:     FunctionType: main (0x1005)
 ; OBJ:     CodeOffset: _main+0x0
 ; OBJ:     Segment: 0x0
-; OBJ:     Flags [ (0x0)
+; OBJ:     Flags [ (0x80)
+; OBJ:       HasOptimizedDebugInfo (0x80)
 ; OBJ:     ]
 ; OBJ:     DisplayName: main
 ; OBJ:     LinkageName: _main

llvm/test/DebugInfo/COFF/inlining.ll

@@ -160,7 +160,8 @@
 ; OBJ:     FunctionType: baz (0x1004)
 ; OBJ:     CodeOffset: ?baz@@YAXXZ+0x0
 ; OBJ:     Segment: 0x0
-; OBJ:     Flags [ (0x0)
+; OBJ:     Flags [ (0x80)
+; OBJ:       HasOptimizedDebugInfo (0x80)
 ; OBJ:     ]
 ; OBJ:     DisplayName: baz
 ; OBJ:     LinkageName: ?baz@@YAXXZ

llvm/test/DebugInfo/COFF/long-name.ll

@@ -5,7 +5,8 @@
 ; CHECK:   FunctionType: {{A+}} (0x1002)
 ; CHECK:   CodeOffset: f+0x0
 ; CHECK:   Segment: 0x0
-; CHECK:   Flags [ (0x0)
+; CHECK:   Flags [ (0x80)
+; CHECK:     HasOptimizedDebugInfo (0x80)
 ; CHECK:   ]
 ; CHECK:   DisplayName: {{A+$}}
 ; CHECK:   LinkageName: f

llvm/test/DebugInfo/COFF/multifunction.ll

@@ -78,7 +78,7 @@
 ; X86-NEXT: .long   4098
 ; X86-NEXT: .secrel32 _x
 ; X86-NEXT: .secidx _x
-; X86-NEXT: .byte   0
+; X86-NEXT: .byte   128
 ; X86-NEXT: .asciz "x"
 ; X86-NEXT: .p2align 2
 ; X86-NEXT: [[PROC_SEGMENT_END]]:
@@ -117,7 +117,7 @@
 ; X86-NEXT: .long   4099
 ; X86-NEXT: .secrel32 _y
 ; X86-NEXT: .secidx _y
-; X86-NEXT: .byte   0
+; X86-NEXT: .byte   128
 ; X86-NEXT: .asciz "y"
 ; X86-NEXT: .p2align 2
 ; X86-NEXT: [[PROC_SEGMENT_END]]:
@@ -156,7 +156,7 @@
 ; X86-NEXT: .long   4100
 ; X86-NEXT: .secrel32 _f
 ; X86-NEXT: .secidx _f
-; X86-NEXT: .byte   0
+; X86-NEXT: .byte   128
 ; X86-NEXT: .asciz "f"
 ; X86-NEXT: .p2align 2
 ; X86-NEXT: [[PROC_SEGMENT_END]]:
@@ -390,7 +390,7 @@
 ; X64-NEXT: .long   4098
 ; X64-NEXT: .secrel32 x
 ; X64-NEXT: .secidx x
-; X64-NEXT: .byte   0
+; X64-NEXT: .byte   128
 ; X64-NEXT: .asciz "x"
 ; X64-NEXT: .p2align 2
 ; X64-NEXT: [[PROC_SEGMENT_END]]:
@@ -428,7 +428,7 @@
 ; X64-NEXT: .long   4099
 ; X64-NEXT: .secrel32 y
 ; X64-NEXT: .secidx y
-; X64-NEXT: .byte   0
+; X64-NEXT: .byte   128
 ; X64-NEXT: .asciz "y"
 ; X64-NEXT: .p2align 2
 ; X64-NEXT: [[PROC_SEGMENT_END]]:
@@ -466,7 +466,7 @@
 ; X64-NEXT: .long   4100
 ; X64-NEXT: .secrel32 f
 ; X64-NEXT: .secidx f
-; X64-NEXT: .byte   0
+; X64-NEXT: .byte   128
 ; X64-NEXT: .asciz "f"
 ; X64-NEXT: .p2align 2
 ; X64-NEXT: [[PROC_SEGMENT_END]]:

llvm/test/DebugInfo/COFF/simple.ll

@@ -58,7 +58,7 @@
 ; X86-NEXT: .long   4098
 ; X86-NEXT: .secrel32 _f
 ; X86-NEXT: .secidx _f
-; X86-NEXT: .byte   0
+; X86-NEXT: .byte   128
 ; X86-NEXT: .asciz "f"
 ; X86-NEXT: .p2align 2
 ; X86-NEXT: [[PROC_SEGMENT_END]]:
@@ -188,7 +188,7 @@
 ; X64-NEXT: .long   4098
 ; X64-NEXT: .secrel32 f
 ; X64-NEXT: .secidx f
-; X64-NEXT: .byte   0
+; X64-NEXT: .byte   128
 ; X64-NEXT: .asciz "f"
 ; X64-NEXT: .p2align 2
 ; X64-NEXT: [[PROC_SEGMENT_END]]:

llvm/test/DebugInfo/COFF/types-array.ll

@@ -58,7 +58,9 @@
 ; CHECK:       FunctionType: f (0x1002)
 ; CHECK:       CodeOffset: ?f@@YAXXZ+0x0
 ; CHECK:       Segment: 0x0
-; CHECK:       Flags [ (0x0)
+; CHECK:       Flags [ (0x81)
+; CHECK:         HasFP (0x1)
+; CHECK:         HasOptimizedDebugInfo (0x80)
 ; CHECK:       ]
 ; CHECK:       DisplayName: f
 ; CHECK:       LinkageName: ?f@@YAXXZ

llvm/test/DebugInfo/COFF/types-basic.ll

@@ -221,7 +221,8 @@
 ; CHECK:       FunctionType: f (0x1002)
 ; CHECK:       CodeOffset: ?f@@YAXMN_J@Z+0x0
 ; CHECK:       Segment: 0x0
-; CHECK:       Flags [ (0x0)
+; CHECK:       Flags [ (0x80)
+; CHECK:         HasOptimizedDebugInfo (0x80)
 ; CHECK:       ]
 ; CHECK:       DisplayName: f
 ; CHECK:       LinkageName: ?f@@YAXMN_J@Z

llvm/test/MC/AArch64/coff-debug.ll

@@ -95,7 +95,9 @@ attributes #0 = { noinline nounwind optnone "correctly-rounded-divide-sqrt-fp-ma
 ; CHECK:       FunctionType: main (0x1002)
 ; CHECK:       CodeOffset: main+0x0
 ; CHECK:       Segment: 0x0
-; CHECK:       Flags [ (0x0)
+; CHECK:       Flags [ (0xC0)
+; CHECK:         HasOptimizedDebugInfo (0x80)
+; CHECK:         IsNoInline (0x40)
 ; CHECK:       ]
 ; CHECK:       DisplayName: main
 ; CHECK:       LinkageName: main