Revert "Reland: [DWARF] Allow cross-CU references of subprogram definitions"

... as well as:
Revert "[DWARF] Defer creating declaration DIEs until we prepare call site info"

This reverts commit fa4701e1979553c2df61698ac1ac212627630442.

This reverts commit 79daafc90308787b52a5d3a7586e82acd5e374b3.

There have been reports of this assert getting hit:

CalleeDIE && "Could not find DIE for call site entry origin

(cherry picked from commit 802bec896171997a7b73dde3857712e0eedeabc1)

4 files changed, 12 insertions, 267 deletions

diff --git a/llvm/test/DebugInfo/AArch64/unretained-declaration-subprogram.ll b/llvm/test/DebugInfo/AArch64/unretained-declaration-subprogram.ll
deleted file mode 100644
index 17ead0e8124..00000000000
--- a/llvm/test/DebugInfo/AArch64/unretained-declaration-subprogram.ll
+++ /dev/null
@@ -1,44 +0,0 @@
-; RUN: llc -mtriple=arm64-apple-ios -filetype=obj < %s -o %t.o
-; RUN: llvm-dwarfdump %t.o | FileCheck %s -implicit-check-not=DW_TAG_subprogram
-
-; The declaration subprogram for "function" is not in the CU's list of
-; retained types. Test that a DWARF call site entry can still be constructed.
-
-; CHECK: DW_TAG_subprogram
-; CHECK:   DW_AT_name {{.*}}__hidden#3_
-; CHECK:   DW_TAG_call_site
-; CHECK:     DW_AT_call_origin (0x{{0+}}[[FUNCTION_DIE:.*]])
-
-; CHECK: 0x{{0+}}[[FUNCTION_DIE]]: DW_TAG_subprogram
-; CHECK:   DW_AT_name {{.*}}function
-
-target datalayout = "e-m:o-i64:64-i128:128-n32:64-S128"
-target triple = "arm64-apple-ios9.0.0"
-
-define i32 @main() local_unnamed_addr !dbg !8 {
-  %1 = tail call [2 x i64] @function([2 x i64] zeroinitializer), !dbg !11
-  %2 = extractvalue [2 x i64] %1, 0, !dbg !11
-  %3 = trunc i64 %2 to i32, !dbg !11
-  ret i32 %3, !dbg !12
-}
-
-declare !dbg !13 [2 x i64] @function([2 x i64]) local_unnamed_addr
-
-!llvm.module.flags = !{!0, !1, !2, !3, !4}
-!llvm.dbg.cu = !{!5}
-!llvm.ident = !{!7}
-
-!0 = !{i32 2, !"SDK Version", [2 x i32] [i32 13, i32 4]}
-!1 = !{i32 7, !"Dwarf Version", i32 4}
-!2 = !{i32 2, !"Debug Info Version", i32 3}
-!3 = !{i32 1, !"wchar_size", i32 4}
-!4 = !{i32 7, !"PIC Level", i32 2}
-!5 = distinct !DICompileUnit(language: DW_LANG_C99, file: !6, producer: "__hidden#0_", isOptimized: true, runtimeVersion: 0, emissionKind: LineTablesOnly, nameTableKind: None)
-!6 = !DIFile(filename: "__hidden#1_", directory: "__hidden#2_")
-!7 = !{!"Apple clang version 11.0.0 (llvm-project fa407d93fd5e618d76378c1ce4e4f517e0563278) (+internal-os)"}
-!8 = distinct !DISubprogram(name: "__hidden#3_", scope: !6, file: !6, line: 9, type: !9, scopeLine: 9, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !5)
-!9 = !DISubroutineType(types: !10)
-!10 = !{}
-!11 = !DILocation(line: 12, column: 10, scope: !8)
-!12 = !DILocation(line: 13, column: 3, scope: !8)
-!13 = !DISubprogram(name: "function", scope: !6, file: !6, line: 7, type: !9, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized)
diff --git a/llvm/test/DebugInfo/MIR/AArch64/dbgcall-site-orr-moves.mir b/llvm/test/DebugInfo/MIR/AArch64/dbgcall-site-orr-moves.mir
index 3e7e6cbfdee..916a14022ba 100644
--- a/llvm/test/DebugInfo/MIR/AArch64/dbgcall-site-orr-moves.mir
+++ b/llvm/test/DebugInfo/MIR/AArch64/dbgcall-site-orr-moves.mir
@@ -159,7 +159,7 @@ body:             |
 ...
 
 # CHECK: DW_TAG_GNU_call_site
-# CHECK-NEXT: DW_AT_abstract_origin ({{.*}} "call_int")
+# CHECK-NEXT: DW_AT_abstract_origin (0x0000002a "call_int")
 #
 # CHECK: DW_TAG_GNU_call_site_parameter
 # CHECK-NEXT: DW_AT_location      (DW_OP_reg0 W0)
@@ -205,7 +205,7 @@ body:             |
 ...
 
 # CHECK: DW_TAG_GNU_call_site
-# CHECK-NEXT: DW_AT_abstract_origin ({{.*}} "call_long")
+# CHECK-NEXT: DW_AT_abstract_origin (0x0000003e "call_long")
 #
 # CHECK: DW_TAG_GNU_call_site_parameter
 # CHECK-NEXT: DW_AT_location      (DW_OP_reg0 W0)
@@ -265,7 +265,7 @@ body:             |
 ...
 
 # CHECK: DW_TAG_GNU_call_site
-# CHECK-NEXT: DW_AT_abstract_origin ({{.*}} "call_int_int")
+# CHECK-NEXT: DW_AT_abstract_origin (0x00000052 "call_int_int")
 #
 # CHECK: DW_TAG_GNU_call_site_parameter
 # FIXME: The DW_AT_location attribute should actually refer to W0! See PR44118.
diff --git a/llvm/test/DebugInfo/MIR/X86/debug-call-site-param.mir b/llvm/test/DebugInfo/MIR/X86/debug-call-site-param.mir
index caee15c2a9e..e79be66cd4e 100644
--- a/llvm/test/DebugInfo/MIR/X86/debug-call-site-param.mir
+++ b/llvm/test/DebugInfo/MIR/X86/debug-call-site-param.mir
@@ -39,11 +39,17 @@
 # CHECK-GNU-NEXT:      DW_AT_location      (DW_OP_reg8 R8)
 # CHECK-GNU-NEXT:      DW_AT_GNU_call_site_value   (DW_OP_breg14 R14+3)
 
-# CHECK-DWARF5: DW_TAG_call_site
-# CHECK-DWARF5:   DW_AT_call_origin ([[getValue_SP:.*]])
+# CHECK-DWARF5: [[getValue_SP:.*]]: DW_TAG_subprogram
+# CHECK-DWARF5-NEXT: DW_AT_name      ("getVal")
 
+# CHECK-DWARF5: [[foo_SP:.*]]: DW_TAG_subprogram
+# CHECK-DWARF5-NEXT: DW_AT_name      ("foo")
+
+# CHECK-DWARF5: DW_TAG_call_site
+# CHECK-DWARF5:   DW_AT_call_origin ([[getValue_SP]])
+#
 # CHECK-DWARF5: DW_TAG_call_site
-# CHECK-DWARF5:   DW_AT_call_origin ([[foo_SP:.*]])
+# CHECK-DWARF5:   DW_AT_call_origin ([[foo_SP]])
 # CHECK-DWARF5:   DW_AT_call_return_pc {{.*}}
 # CHECK-DWARF5-EMPTY:
 # CHECK-DWARF5:         DW_TAG_call_site_parameter
@@ -65,12 +71,6 @@
 # CHECK-DWARF5-NEXT:      DW_AT_location      (DW_OP_reg8 R8)
 # CHECK-DWARF5-NEXT:      DW_AT_call_value   (DW_OP_breg14 R14+3)
 
-# CHECK-DWARF5: [[getValue_SP]]: DW_TAG_subprogram
-# CHECK-DWARF5-NEXT: DW_AT_name      ("getVal")
-
-# CHECK-DWARF5: [[foo_SP]]: DW_TAG_subprogram
-# CHECK-DWARF5-NEXT: DW_AT_name      ("foo")
-
 --- |
   ; ModuleID = 'test.c'
   source_filename = "test.c"
diff --git a/llvm/test/DebugInfo/X86/lto-cross-cu-call-origin-ref.ll b/llvm/test/DebugInfo/X86/lto-cross-cu-call-origin-ref.ll
deleted file mode 100644
index 00715841ab5..00000000000
--- a/llvm/test/DebugInfo/X86/lto-cross-cu-call-origin-ref.ll
+++ /dev/null
@@ -1,211 +0,0 @@
-; RUN: llc -mtriple=x86_64-apple-darwin -filetype=obj < %s -o %t.o
-; RUN: llvm-dwarfdump %t.o | FileCheck %s -implicit-check-not=DW_TAG_subprogram
-; RUN: llvm-dwarfdump --verify %t.o
-
-; This test checks that cross-CU references within call site tags to subprogram
-; definitions are well-formed. There are 5 cases checked in this test. Each set
-; of checks is numbered and has a brief summary.
-
-; Instructions to regenerate the IR:
-; clang -O1 -g -emit-llvm -o a.bc -c a.c
-; clang -O1 -g -emit-llvm -o b.bc -c b.c
-; llvm-link -o linked.bc a.bc b.bc
-; opt -O1 linked.bc -o merged.bc
-
-; Source:
-; // a.c
-; __attribute__((optnone)) void noinline_func_in_a() {}
-;
-; __attribute__((optnone)) static void foo() {}
-; __attribute__((always_inline)) void always_inline_helper_in_a_that_calls_foo() {
-;   foo();
-; }
-;
-; extern void func_from_b();
-; void call_func_in_b_from_a() {
-;   func_from_b();
-; }
-;
-; // b.c
-; extern void noinline_func_in_a();
-; void call_noinline_func_in_a_from_b() {
-;   noinline_func_in_a();
-; }
-;
-; __attribute__((optnone)) void foo() {}
-; extern void always_inline_helper_in_a_that_calls_foo();
-; void call_both_foos_from_b() {
-;   foo();
-;   always_inline_helper_in_a_that_calls_foo();
-; }
-;
-; __attribute__((optnone)) void func_from_b() {}
-; void call_func_in_b_from_b() {
-;   func_from_b();
-; }
-
-; === CU for a.c ===
-
-; CHECK: DW_TAG_compile_unit
-; CHECK:   DW_AT_name ("a.c")
-
-; CHECK: 0x{{0+}}[[NOINLINE_FUNC_IN_A:.*]]: DW_TAG_subprogram
-; CHECK:   DW_AT_name ("noinline_func_in_a")
-
-; 1) Check that "always_inline_helper_in_a_that_calls_foo" calls the "foo" in
-; a.c, and *not* the "foo" in b.c.
-; CHECK: 0x{{0+}}[[ALWAYS_INLINE_HELPER_IN_A:.*]]: DW_TAG_subprogram
-; CHECK:   DW_AT_abstract_origin ({{.*}} "always_inline_helper_in_a_that_calls_foo")
-; CHECK:   DW_TAG_call_site
-; CHECK-NEXT: DW_AT_call_origin (0x{{0+}}[[FOO_IN_A:.*]])
-
-; CHECK: 0x{{0+}}[[FOO_IN_A]]: DW_TAG_subprogram
-; CHECK:   DW_AT_name ("foo")
-
-; 2) Check that "call_func_in_b_from_a" has a cross-CU ref into b.c.
-; CHECK: DW_TAG_subprogram
-; CHECK:   DW_AT_name ("call_func_in_b_from_a")
-; CHECK:   DW_TAG_call_site
-; CHECK-NEXT: DW_AT_call_origin (0x{{0+}}[[FUNC_FROM_B:.*]])
-
-; CHECK: DW_TAG_subprogram
-; CHECK:   DW_AT_name ("always_inline_helper_in_a_that_calls_foo")
-; CHECK:   DW_AT_inline (DW_INL_inlined)
-
-; === CU for b.c ===
-
-; CHECK: DW_TAG_compile_unit
-; CHECK:   DW_AT_name ("b.c")
-
-; 3) Validate the cross-CU ref from "call_func_in_b_from_a" in a.c.
-; CHECK: 0x{{0+}}[[FUNC_FROM_B]]: DW_TAG_subprogram
-; CHECK:   DW_AT_name ("func_from_b")
-
-; 4) Validate the cross-CU ref from "call_noinline_func_in_a_from_b" in b.c.
-; CHECK: DW_TAG_subprogram
-; CHECK:   DW_AT_name ("call_noinline_func_in_a_from_b")
-; CHECK:   DW_TAG_call_site
-; CHECK-NEXT: DW_AT_call_origin (0x{{0+}}[[NOINLINE_FUNC_IN_A]])
-
-; CHECK: 0x{{0+}}[[FOO_IN_B:.*]]: DW_TAG_subprogram
-; CHECK:   DW_AT_name ("foo")
-
-; 5) Validate that we correctly emit a cross-CU ref when the call is inlined
-; from another CU.
-; CHECK: DW_TAG_subprogram
-; CHECK:   DW_AT_name ("call_both_foos_from_b")
-; CHECK:   DW_TAG_call_site
-; CHECK-NEXT: DW_AT_call_origin (0x{{0+}}[[FOO_IN_B]])
-; CHECK:   DW_TAG_call_site
-; CHECK-NEXT: DW_AT_call_origin (0x{{0+}}[[FOO_IN_A]])
-
-; CHECK: DW_TAG_subprogram
-; CHECK:   DW_AT_name ("call_func_in_b_from_b")
-; CHECK:   DW_TAG_call_site
-; CHECK-NEXT: DW_AT_call_origin (0x{{0+}}[[FUNC_FROM_B]])
-
-target datalayout = "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
-target triple = "x86_64-apple-macosx10.14.0"
-
-define void @noinline_func_in_a() local_unnamed_addr #0 !dbg !17 {
-entry:
-  ret void, !dbg !20
-}
-
-define void @always_inline_helper_in_a_that_calls_foo() local_unnamed_addr #1 !dbg !21 {
-entry:
-  tail call fastcc void @foo.2(), !dbg !22
-  ret void, !dbg !23
-}
-
-define internal fastcc void @foo.2() unnamed_addr #0 !dbg !24 {
-entry:
-  ret void, !dbg !25
-}
-
-define void @call_func_in_b_from_a() local_unnamed_addr !dbg !26 {
-entry:
-  tail call void @func_from_b() #3, !dbg !27
-  ret void, !dbg !28
-}
-
-define void @call_noinline_func_in_a_from_b() local_unnamed_addr !dbg !29 {
-entry:
-  tail call void @noinline_func_in_a() #3, !dbg !30
-  ret void, !dbg !31
-}
-
-define void @foo() local_unnamed_addr #0 !dbg !32 {
-entry:
-  ret void, !dbg !33
-}
-
-define void @call_both_foos_from_b() local_unnamed_addr !dbg !34 {
-entry:
-  tail call void @foo(), !dbg !35
-  tail call fastcc void @foo.2() #3, !dbg !36
-  ret void, !dbg !38
-}
-
-define void @func_from_b() local_unnamed_addr #0 !dbg !39 {
-entry:
-  ret void, !dbg !40
-}
-
-define void @call_func_in_b_from_b() local_unnamed_addr !dbg !41 {
-entry:
-  tail call void @func_from_b(), !dbg !42
-  ret void, !dbg !43
-}
-
-attributes #0 = { noinline }
-attributes #1 = { alwaysinline }
-
-!llvm.dbg.cu = !{!0, !7}
-!llvm.ident = !{!12, !12}
-!llvm.module.flags = !{!13, !14, !15, !16}
-
-!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 10.0.0 (git@github.com:llvm/llvm-project.git 310e85309f870ee7347ef979d7d8da9bf28e92ea)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !3, nameTableKind: None)
-!1 = !DIFile(filename: "a.c", directory: "/Users/vsk/tmp/lto-entry-vals")
-!2 = !{}
-!3 = !{!4}
-!4 = !DISubprogram(name: "func_from_b", scope: !1, file: !1, line: 8, type: !5, spFlags: DISPFlagOptimized, retainedNodes: !2)
-!5 = !DISubroutineType(types: !6)
-!6 = !{null, null}
-!7 = distinct !DICompileUnit(language: DW_LANG_C99, file: !8, producer: "clang version 10.0.0 (git@github.com:llvm/llvm-project.git 310e85309f870ee7347ef979d7d8da9bf28e92ea)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !9, nameTableKind: None)
-!8 = !DIFile(filename: "b.c", directory: "/Users/vsk/tmp/lto-entry-vals")
-!9 = !{!10, !11}
-!10 = !DISubprogram(name: "noinline_func_in_a", scope: !8, file: !8, line: 1, type: !5, spFlags: DISPFlagOptimized, retainedNodes: !2)
-!11 = !DISubprogram(name: "always_inline_helper_in_a_that_calls_foo", scope: !8, file: !8, line: 7, type: !5, spFlags: DISPFlagOptimized, retainedNodes: !2)
-!12 = !{!"clang version 10.0.0 (git@github.com:llvm/llvm-project.git 310e85309f870ee7347ef979d7d8da9bf28e92ea)"}
-!13 = !{i32 7, !"Dwarf Version", i32 4}
-!14 = !{i32 2, !"Debug Info Version", i32 3}
-!15 = !{i32 1, !"wchar_size", i32 4}
-!16 = !{i32 7, !"PIC Level", i32 2}
-!17 = distinct !DISubprogram(name: "noinline_func_in_a", scope: !1, file: !1, line: 1, type: !18, scopeLine: 1, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !2)
-!18 = !DISubroutineType(types: !19)
-!19 = !{null}
-!20 = !DILocation(line: 1, column: 53, scope: !17)
-!21 = distinct !DISubprogram(name: "always_inline_helper_in_a_that_calls_foo", scope: !1, file: !1, line: 4, type: !18, scopeLine: 4, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !2)
-!22 = !DILocation(line: 5, column: 3, scope: !21)
-!23 = !DILocation(line: 6, column: 1, scope: !21)
-!24 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 3, type: !18, scopeLine: 3, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagLocalToUnit | DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !2)
-!25 = !DILocation(line: 3, column: 45, scope: !24)
-!26 = distinct !DISubprogram(name: "call_func_in_b_from_a", scope: !1, file: !1, line: 9, type: !18, scopeLine: 9, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !2)
-!27 = !DILocation(line: 10, column: 3, scope: !26)
-!28 = !DILocation(line: 11, column: 1, scope: !26)
-!29 = distinct !DISubprogram(name: "call_noinline_func_in_a_from_b", scope: !8, file: !8, line: 2, type: !18, scopeLine: 2, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !7, retainedNodes: !2)
-!30 = !DILocation(line: 3, column: 3, scope: !29)
-!31 = !DILocation(line: 4, column: 1, scope: !29)
-!32 = distinct !DISubprogram(name: "foo", scope: !8, file: !8, line: 6, type: !18, scopeLine: 6, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !7, retainedNodes: !2)
-!33 = !DILocation(line: 6, column: 38, scope: !32)
-!34 = distinct !DISubprogram(name: "call_both_foos_from_b", scope: !8, file: !8, line: 8, type: !18, scopeLine: 8, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !7, retainedNodes: !2)
-!35 = !DILocation(line: 9, column: 3, scope: !34)
-!36 = !DILocation(line: 5, column: 3, scope: !21, inlinedAt: !37)
-!37 = distinct !DILocation(line: 10, column: 3, scope: !34)
-!38 = !DILocation(line: 11, column: 1, scope: !34)
-!39 = distinct !DISubprogram(name: "func_from_b", scope: !8, file: !8, line: 13, type: !18, scopeLine: 13, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !7, retainedNodes: !2)
-!40 = !DILocation(line: 13, column: 46, scope: !39)
-!41 = distinct !DISubprogram(name: "call_func_in_b_from_b", scope: !8, file: !8, line: 14, type: !18, scopeLine: 14, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !7, retainedNodes: !2)
-!42 = !DILocation(line: 15, column: 3, scope: !41)
-!43 = !DILocation(line: 16, column: 1, scope: !41)