Revert "[DebugInfo] Remove some users of DBG_VALUEs IsIndirect field"

This reverts commit ed29dbaafa49bb8c9039a35f768244c394411fea.

I'm backing out D68945, which as the discussion for D73526 shows, doesn't
seem to handle the -O0 path through the codegen backend correctly. I'll
reland the patch when a fix is worked out, apologies for all the churn.
The two parent commits are part of this revert too.

Conflicts:
	llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
	llvm/test/DebugInfo/X86/dbg-addr-dse.ll

SelectionDAGBuilder conflict is due to a nearby change in e39e2b4a79c6
that's technically unrelated. dbg-addr-dse.ll conflicted because
41206b61e30c (legitimately) changes the order of two lines.

There are further modifications to dbg-value-func-arg.ll: it landed after
the patch being reverted, and I've converted indirection to be represented
by the isIndirect field rather than DW_OP_deref.

(cherry picked from commit 6531a78ac4b5b229bce272706593a0bc873877d7)

9 files changed, 25 insertions, 51 deletions

diff --git a/llvm/test/DebugInfo/X86/dbg-addr-dse.ll b/llvm/test/DebugInfo/X86/dbg-addr-dse.ll
index f6f653a1d98..a817474c16c 100644
--- a/llvm/test/DebugInfo/X86/dbg-addr-dse.ll
+++ b/llvm/test/DebugInfo/X86/dbg-addr-dse.ll
@@ -3,10 +3,6 @@
 ; RUN: FileCheck %s < %t.s --check-prefix=ASM
 ; RUN: llvm-dwarfdump %t.o | FileCheck %s --check-prefix=DWARF
 
-; XFAIL: *
-; See PR41992, the third and final dbg.value disappears after
-; LiveDebugVariables.
-
 ; In this example, the variable lives mostly in memory, but at the point of the
 ; assignment to global, it lives nowhere, and is described as the constant
 ; value 1.
@@ -51,11 +47,11 @@ entry:
 
 ; ASM-LABEL: f: # @f
 ; ASM: movl    %ecx, [[OFF_X:[0-9]+]](%rsp)
-; ASM: #DEBUG_VALUE: f:x <- [DW_OP_plus_uconst [[OFF_X]], DW_OP_deref] $rsp
+; ASM: #DEBUG_VALUE: f:x <- [DW_OP_plus_uconst [[OFF_X]]] [$rsp+0]
 ; ASM: callq   escape
 ; ASM: #DEBUG_VALUE: f:x <- 1
 ; ASM: movl    $1, global(%rip)
-; ASM: #DEBUG_VALUE: f:x <- [DW_OP_plus_uconst [[OFF_X]], DW_OP_deref] $rsp
+; ASM: #DEBUG_VALUE: f:x <- [DW_OP_plus_uconst [[OFF_X]]] [$rsp+0]
 ; ASM: movl    $2, [[OFF_X]](%rsp)
 ; ASM: callq   escape
 ; ASM: retq
diff --git a/llvm/test/DebugInfo/X86/dbg-addr.ll b/llvm/test/DebugInfo/X86/dbg-addr.ll
index 48cb739be45..4e27cf5754c 100644
--- a/llvm/test/DebugInfo/X86/dbg-addr.ll
+++ b/llvm/test/DebugInfo/X86/dbg-addr.ll
@@ -7,7 +7,7 @@
 ; is control-dependent.
 
 ; CHECK-LABEL: use_dbg_addr:
-; CHECK: #DEBUG_VALUE: use_dbg_addr:o <- [DW_OP_deref] $rsp
+; CHECK: #DEBUG_VALUE: use_dbg_addr:o <- [$rsp+0]
 
 ; DWARF: DW_TAG_variable
 ; DWARF-NEXT:              DW_AT_location (DW_OP_fbreg +0)
diff --git a/llvm/test/DebugInfo/X86/live-debug-vars-dse.mir b/llvm/test/DebugInfo/X86/live-debug-vars-dse.mir
index bc20ebf5d4e..9d6ec9f4eca 100644
--- a/llvm/test/DebugInfo/X86/live-debug-vars-dse.mir
+++ b/llvm/test/DebugInfo/X86/live-debug-vars-dse.mir
@@ -1,9 +1,5 @@
 # RUN: llc -start-after=machine-scheduler %s -o - | FileCheck %s
 
-# XFAIL: *
-# See PR41992, the third and final dbg.value disappears after
-# LiveDebugVariables.
-
 # C source:
 # void escape(int *);
 # extern int global;
@@ -17,12 +13,12 @@
 
 # CHECK-LABEL: f: # @f
 # CHECK: movl    %ecx, [[OFF_X:[0-9]+]](%rsp)
-# CHECK: #DEBUG_VALUE: f:x <- [DW_OP_plus_uconst [[OFF_X]], DW_OP_deref] $rsp
+# CHECK: #DEBUG_VALUE: f:x <- [DW_OP_plus_uconst [[OFF_X]]] [$rsp+0]
 # CHECK: leaq [[OFF_X]](%rsp), %rsi
 # CHECK: callq   escape
 # CHECK: #DEBUG_VALUE: f:x <- 1
 # CHECK: movl    $1, global(%rip)
-# CHECK: #DEBUG_VALUE: f:x <- [DW_OP_plus_uconst [[OFF_X]], DW_OP_deref] $rsp
+# CHECK: #DEBUG_VALUE: f:x <- [DW_OP_plus_uconst [[OFF_X]]] [$rsp+0]
 # CHECK: movl    $2, [[OFF_X]](%rsp)
 # CHECK: callq   escape
 # CHECK: retq
@@ -46,11 +42,11 @@
   entry:
     %x.addr = alloca i32, align 4
     store i32 %x, i32* %x.addr, align 4
-    call void @llvm.dbg.value(metadata i32* %x.addr, metadata !13, metadata !DIExpression(DW_OP_deref)), !dbg !14
+    call void @llvm.dbg.value(metadata i32* %x.addr, metadata !13, metadata !DIExpression()), !dbg !14
     call void @escape(i32* %x.addr), !dbg !15
     call void @llvm.dbg.value(metadata i32 1, metadata !13, metadata !DIExpression()), !dbg !16
     store i32 1, i32* @global, align 4, !dbg !17
-    call void @llvm.dbg.value(metadata i32* %x.addr, metadata !13, metadata !DIExpression(DW_OP_deref)), !dbg !18
+    call void @llvm.dbg.value(metadata i32* %x.addr, metadata !13, metadata !DIExpression()), !dbg !18
     store i32 2, i32* %x.addr, align 4, !dbg !18
     call void @escape(i32* %x.addr), !dbg !19
     ret void, !dbg !20
@@ -132,7 +128,7 @@ body:             |
   
     %0 = COPY $ecx
     MOV32mr %stack.0.x.addr, 1, _, 0, _, %0 :: (store 4 into %ir.x.addr)
-    DBG_VALUE %stack.0.x.addr, $noreg, !13, !DIExpression(DW_OP_deref), debug-location !14
+    DBG_VALUE %stack.0.x.addr, 0, !13, !DIExpression(), debug-location !14
     ADJCALLSTACKDOWN64 32, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp, debug-location !15
     %1 = LEA64r %stack.0.x.addr, 1, _, 0, _
     $rcx = COPY %1, debug-location !15
@@ -140,7 +136,7 @@ body:             |
     ADJCALLSTACKUP64 32, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp, debug-location !15
     DBG_VALUE 1, _, !13, !DIExpression(), debug-location !16
     MOV32mi $rip, 1, _, @global, _, 1, debug-location !17 :: (store 4 into @global)
-    DBG_VALUE %stack.0.x.addr, $noreg, !13, !DIExpression(DW_OP_deref), debug-location !18
+    DBG_VALUE %stack.0.x.addr, 0, !13, !DIExpression(), debug-location !18
     MOV32mi %stack.0.x.addr, 1, _, 0, _, 2, debug-location !18 :: (store 4 into %ir.x.addr)
     ADJCALLSTACKDOWN64 32, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp, debug-location !19
     $rcx = COPY %1, debug-location !19
diff --git a/llvm/test/DebugInfo/X86/op_deref.ll b/llvm/test/DebugInfo/X86/op_deref.ll
index a1af8fac780..5de9976d6de 100644
--- a/llvm/test/DebugInfo/X86/op_deref.ll
+++ b/llvm/test/DebugInfo/X86/op_deref.ll
@@ -6,12 +6,10 @@
 ; RUN:     | FileCheck %s -check-prefix=CHECK -check-prefix=DWARF3
 
 ; DWARF4: DW_AT_location [DW_FORM_sec_offset]                      (0x00000000
-; DWARF4-NEXT:  {{.*}}: DW_OP_breg1 RDX+0{{$}}
-; DWARF4-NEXT:  {{.*}}: DW_OP_breg6 RBP-{{[0-9]+}}, DW_OP_deref)
+; DWARF4-NEXT:  {{.*}}: DW_OP_breg1 RDX+0, DW_OP_deref
 
 ; DWARF3: DW_AT_location [DW_FORM_data4]                      (0x00000000
-; DWARF3-NEXT:  {{.*}}: DW_OP_breg1 RDX+0{{$}}
-; DWARF3-NEXT:  {{.*}}: DW_OP_breg6 RBP-{{[0-9]+}}, DW_OP_deref)
+; DWARF3-NEXT:  {{.*}}: DW_OP_breg1 RDX+0, DW_OP_deref
 
 ; CHECK-NOT: DW_TAG
 ; CHECK: DW_AT_name [DW_FORM_strp]  ( .debug_str[0x00000067] = "vla")
@@ -19,13 +17,11 @@
 ; Check the DEBUG_VALUE comments for good measure.
 ; RUN: llc -O0 -mtriple=x86_64-apple-darwin %s -o - -filetype=asm | FileCheck %s -check-prefix=ASM-CHECK
 ; vla should have a register-indirect address at one point.
-; ASM-CHECK: DEBUG_VALUE: vla <- [DW_OP_deref] $rdx
-; vla ptr is spilt too, it should have a stack location,
-; ASM-CHECK: DEBUG_VALUE: vla <- [DW_OP_constu {{[0-9]+}}, DW_OP_minus, DW_OP_deref] [$rbp+0]
+; ASM-CHECK: DEBUG_VALUE: vla <- [DW_OP_deref] [$rdx+0]
 ; ASM-CHECK: DW_OP_breg1
 
 ; RUN: llvm-as %s -o - | llvm-dis - | FileCheck %s --check-prefix=PRETTY-PRINT
-; PRETTY-PRINT: DIExpression()
+; PRETTY-PRINT: DIExpression(DW_OP_deref)
 
 define void @testVLAwithSize(i32 %s) nounwind uwtable ssp !dbg !5 {
 entry:
@@ -108,4 +104,4 @@ declare void @llvm.stackrestore(i8*) nounwind
 !27 = !DILocation(line: 8, column: 1, scope: !13)
 !28 = !DIFile(filename: "bar.c", directory: "/Users/echristo/tmp")
 !29 = !{i32 1, !"Debug Info Version", i32 3}
-!30 = !DIExpression()
+!30 = !DIExpression(DW_OP_deref)
diff --git a/llvm/test/DebugInfo/X86/parameters.ll b/llvm/test/DebugInfo/X86/parameters.ll
index 3330e968aa1..ed0048cc15e 100644
--- a/llvm/test/DebugInfo/X86/parameters.ll
+++ b/llvm/test/DebugInfo/X86/parameters.ll
@@ -28,7 +28,7 @@
 ; CHECK: DW_AT_name{{.*}} = "func"
 ; CHECK: DW_TAG_formal_parameter
 ; CHECK: DW_AT_location {{.*}}
-; CHECK-NEXT: DW_OP_breg4 RSI+0)
+; CHECK-NEXT: DW_OP_breg4 RSI+0, DW_OP_deref
 ; CHECK-NOT: DW_TAG
 ; CHECK: DW_AT_name{{.*}} = "f"
 
@@ -38,8 +38,8 @@
 ; CHECK: DW_AT_location{{.*}}(DW_OP_fbreg +23)
 ; CHECK: DW_TAG_formal_parameter
 ; CHECK: DW_AT_location{{.*}}(
-; CHECK-NEXT: {{.*}}: DW_OP_breg4 RSI+0{{$}}
-; CHECK-NEXT: {{.*}}: DW_OP_breg7 RSP+8, DW_OP_deref)
+; CHECK-NEXT: {{.*}}: DW_OP_breg4 RSI+0, DW_OP_deref
+; CHECK-NEXT: {{.*}}: DW_OP_breg7 RSP+8, DW_OP_deref, DW_OP_deref)
 ; CHECK-NOT: DW_TAG
 ; CHECK: DW_AT_name{{.*}} = "g"
 
@@ -48,7 +48,7 @@
 ; Function Attrs: uwtable
 define void @_ZN7pr147634funcENS_3fooE(%"struct.pr14763::foo"* noalias sret %agg.result, %"struct.pr14763::foo"* %f) #0 !dbg !4 {
 entry:
-  call void @llvm.dbg.declare(metadata %"struct.pr14763::foo"* %f, metadata !22, metadata !DIExpression()), !dbg !24
+  call void @llvm.dbg.declare(metadata %"struct.pr14763::foo"* %f, metadata !22, metadata !DIExpression(DW_OP_deref)), !dbg !24
   call void @_ZN7pr147633fooC1ERKS0_(%"struct.pr14763::foo"* %agg.result, %"struct.pr14763::foo"* %f), !dbg !25
   ret void, !dbg !25
 }
@@ -65,7 +65,7 @@ entry:
   %frombool = zext i1 %b to i8
   store i8 %frombool, i8* %b.addr, align 1
   call void @llvm.dbg.declare(metadata i8* %b.addr, metadata !26, metadata !DIExpression()), !dbg !27
-  call void @llvm.dbg.declare(metadata %"struct.pr14763::foo"* %g, metadata !28, metadata !DIExpression()), !dbg !27
+  call void @llvm.dbg.declare(metadata %"struct.pr14763::foo"* %g, metadata !28, metadata !DIExpression(DW_OP_deref)), !dbg !27
   %0 = load i8, i8* %b.addr, align 1, !dbg !29
   %tobool = trunc i8 %0 to i1, !dbg !29
   br i1 %tobool, label %if.then, label %if.end, !dbg !29
diff --git a/llvm/test/DebugInfo/X86/safestack-byval.ll b/llvm/test/DebugInfo/X86/safestack-byval.ll
index 1d53908b497..a653cd78b91 100644
--- a/llvm/test/DebugInfo/X86/safestack-byval.ll
+++ b/llvm/test/DebugInfo/X86/safestack-byval.ll
@@ -14,7 +14,7 @@
 ; }
 
 ; CHECK: ![[ZZZ:.*]] = !DILocalVariable(name: "zzz",
-; CHECK: DBG_VALUE {{.*}} ![[ZZZ]], !DIExpression(DW_OP_constu, 400, DW_OP_minus, DW_OP_deref)
+; CHECK: DBG_VALUE {{.*}} ![[ZZZ]], !DIExpression(DW_OP_deref, DW_OP_constu, 400, DW_OP_minus)
 
 %struct.S = type { [100 x i32] }
 
@@ -78,7 +78,7 @@ attributes #2 = { argmemonly nounwind }
 !20 = !{i32 2, !"Debug Info Version", i32 3}
 !21 = !{!"clang version 3.8.0 (trunk 254107) (llvm/trunk 254109)"}
 !22 = !DILocation(line: 8, column: 9, scope: !12)
-!23 = !DIExpression(DW_OP_constu, 400, DW_OP_minus)
+!23 = !DIExpression(DW_OP_deref, DW_OP_constu, 400, DW_OP_minus)
 !24 = !DILocation(line: 8, column: 28, scope: !12)
 !25 = !DIExpression()
 !26 = !DILocation(line: 9, column: 10, scope: !12)
diff --git a/llvm/test/DebugInfo/X86/spill-indirect-nrvo.ll b/llvm/test/DebugInfo/X86/spill-indirect-nrvo.ll
index 1ac90ead110..82c852034ae 100644
--- a/llvm/test/DebugInfo/X86/spill-indirect-nrvo.ll
+++ b/llvm/test/DebugInfo/X86/spill-indirect-nrvo.ll
@@ -21,7 +21,7 @@
 ; }
 
 ; CHECK-LABEL: _Z10get_stringv:
-; CHECK: #DEBUG_VALUE: get_string:result <- [DW_OP_deref] $rdi
+; CHECK: #DEBUG_VALUE: get_string:result <- [$rdi+0]
 ; CHECK: movq   %rdi, [[OFFS:[0-9]+]](%rsp)          # 8-byte Spill
 ; CHECK: #DEBUG_VALUE: get_string:result <- [DW_OP_plus_uconst [[OFFS]], DW_OP_deref] [$rsp+0]
 ; CHECK: callq  _ZN6stringC1Ei
diff --git a/llvm/test/DebugInfo/X86/spill-nontrivial-param.ll b/llvm/test/DebugInfo/X86/spill-nontrivial-param.ll
index 9712f4f48f0..08793c13f56 100644
--- a/llvm/test/DebugInfo/X86/spill-nontrivial-param.ll
+++ b/llvm/test/DebugInfo/X86/spill-nontrivial-param.ll
@@ -20,7 +20,7 @@
 ; }
 
 ; CHECK-LABEL: _Z3foo10NonTrivial:
-; CHECK: #DEBUG_VALUE: foo:nt <- [DW_OP_deref] $rdi
+; CHECK: #DEBUG_VALUE: foo:nt <- [$rdi+0]
 ; CHECK: movq    %rdi, -8(%rsp)          # 8-byte Spill
 ; CHECK: #DEBUG_VALUE: foo:nt <- [DW_OP_constu 8, DW_OP_minus, DW_OP_deref] [$rsp+0]
 ; CHECK: #APP
diff --git a/llvm/test/DebugInfo/X86/vla.ll b/llvm/test/DebugInfo/X86/vla.ll
index 4e4f7fbb36b..7d4aff8470d 100644
--- a/llvm/test/DebugInfo/X86/vla.ll
+++ b/llvm/test/DebugInfo/X86/vla.ll
@@ -1,21 +1,7 @@
 ; RUN: llc -O0 -mtriple=x86_64-apple-darwin -filetype=asm %s -o - | FileCheck %s
-; RUN: llc -O0 -mtriple=x86_64-apple-darwin -filetype=obj %s -o - | llvm-dwarfdump - --name=a | FileCheck --check-prefix=OBJFILE %s
-; REQUIRES: object-emission
-;
 ; Ensure that we generate an indirect location for the variable length array a.
-;
-; CHECK: ##DEBUG_VALUE: vla:a <- [DW_OP_deref] {{\$r[a-z]+}}
+; CHECK: ##DEBUG_VALUE: vla:a <- [DW_OP_deref] [{{\$r[a-z]+}}+0]
 ; CHECK: DW_OP_breg{{[0-9]}}
-;
-; Ensure there's only one level of indirection in the vla location -- it should
-; be a memory location. Base register can be any allocatable one; variables are
-; filtered by --name arg to llvm-dwarfdump.
-;
-; OBJFILE: DW_TAG_variable
-; OBJFILE: DW_AT_location
-; OBJFILE-NEXT: ): DW_OP_breg{{[0-9]+}} R{{[0-9A-Z]+}}+0)
-; OBJFILE: DW_AT_name ("a")
-;
 ; rdar://problem/13658587
 ;
 ; generated from:
@@ -47,7 +33,7 @@ entry:
   %2 = call i8* @llvm.stacksave(), !dbg !17
   store i8* %2, i8** %saved_stack, !dbg !17
   %vla = alloca i32, i64 %1, align 16, !dbg !17
-  call void @llvm.dbg.declare(metadata i32* %vla, metadata !18, metadata !DIExpression()), !dbg !17
+  call void @llvm.dbg.declare(metadata i32* %vla, metadata !18, metadata !DIExpression(DW_OP_deref)), !dbg !17
   %arrayidx = getelementptr inbounds i32, i32* %vla, i64 0, !dbg !22
   store i32 42, i32* %arrayidx, align 4, !dbg !22
   %3 = load i32, i32* %n.addr, align 4, !dbg !23