[IR] Remove the DIExpression field from DIGlobalVariable.

This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

llvm-svn: 289902

11 files changed, 22 insertions, 20 deletions

diff --git a/llvm/test/Transforms/GCOVProfiling/return-block.ll b/llvm/test/Transforms/GCOVProfiling/return-block.ll
index 51dde5724fe..0170569b2ec 100644
--- a/llvm/test/Transforms/GCOVProfiling/return-block.ll
+++ b/llvm/test/Transforms/GCOVProfiling/return-block.ll
@@ -61,7 +61,7 @@ attributes #2 = { nounwind }
 !6 = !DISubroutineType(types: !7)
 !7 = !{null}
 !8 = !{!9}
-!9 = !DIGlobalVariable(name: "A", line: 3, isLocal: false, isDefinition: true, scope: null, file: !5, type: !10)
+!9 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "A", line: 3, isLocal: false, isDefinition: true, scope: null, file: !5, type: !10))
 !10 = !DIBasicType(tag: DW_TAG_base_type, name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
 !11 = !{i32 2, !"Dwarf Version", i32 4}
 !12 = !{i32 2, !"Debug Info Version", i32 3}
diff --git a/llvm/test/Transforms/GlobalMerge/debug-info.ll b/llvm/test/Transforms/GlobalMerge/debug-info.ll
index 04f81b54877..2ec7b117313 100644
--- a/llvm/test/Transforms/GlobalMerge/debug-info.ll
+++ b/llvm/test/Transforms/GlobalMerge/debug-info.ll
@@ -14,12 +14,14 @@ define void @use1() {
   ret void
 }
 
-; CHECK: [[A]] = distinct !DIGlobalVariable(name: "a", scope: null, isLocal: false, isDefinition: true)
-; CHECK: [[B]] = distinct !DIGlobalVariable(name: "b", scope: null, isLocal: false, isDefinition: true, expr: [[EXPR:![0-9]+]])
+; CHECK: [[A]] = !DIGlobalVariableExpression(var: [[AVAR:![0-9]+]])
+; CHECK: [[AVAR]] = !DIGlobalVariable(name: "a", scope: null, isLocal: false, isDefinition: true)
+; CHECK: [[B]] = !DIGlobalVariableExpression(var: [[BVAR:![0-9]+]], expr: [[EXPR:![0-9]+]])
+; CHECK: [[BVAR]] = !DIGlobalVariable(name: "b", scope: null, isLocal: false, isDefinition: true)
 ; CHECK: [[EXPR]] = !DIExpression(DW_OP_plus, 4)
 
 !llvm.module.flags = !{!2, !3}
-!0 = distinct !DIGlobalVariable(name: "a")
-!1 = distinct !DIGlobalVariable(name: "b")
+!0 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "a"))
+!1 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "b"))
 !2 = !{i32 2, !"Debug Info Version", i32 3}
 !3 = !{i32 2, !"Dwarf Version", i32 4}
diff --git a/llvm/test/Transforms/GlobalOpt/2009-03-05-dbg.ll b/llvm/test/Transforms/GlobalOpt/2009-03-05-dbg.ll
index 587ec9bf7f3..ed77e31e3a1 100644
--- a/llvm/test/Transforms/GlobalOpt/2009-03-05-dbg.ll
+++ b/llvm/test/Transforms/GlobalOpt/2009-03-05-dbg.ll
@@ -55,7 +55,7 @@ return:                                           ; preds = %bb2
 declare void @llvm.dbg.value(metadata, i64, metadata, metadata) nounwind readnone
 
 !llvm.dbg.cu = !{!1}
-!0 = !DIGlobalVariable(name: "Stop", line: 2, isLocal: true, isDefinition: true, scope: !1, file: !1, type: !2)
+!0 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "Stop", line: 2, isLocal: true, isDefinition: true, scope: !1, file: !1, type: !2))
 !1 = distinct !DICompileUnit(language: DW_LANG_C89, producer: "4.2.1 (Based on Apple Inc. build 5658) (LLVM build)", isOptimized: true, emissionKind: FullDebug, file: !20, enums: !21, retainedTypes: !21, globals: !{!0})
 !2 = !DIBasicType(tag: DW_TAG_base_type, name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
 !3 = !DILocalVariable(name: "i", line: 4, arg: 1, scope: !4, file: !1, type: !2)
diff --git a/llvm/test/Transforms/Inline/alloca-dbgdeclare.ll b/llvm/test/Transforms/Inline/alloca-dbgdeclare.ll
index 78b888fd652..aeb7e055e99 100644
--- a/llvm/test/Transforms/Inline/alloca-dbgdeclare.ll
+++ b/llvm/test/Transforms/Inline/alloca-dbgdeclare.ll
@@ -107,8 +107,8 @@ attributes #3 = { noreturn nounwind }
 !23 = !{null}
 !24 = distinct !DISubprogram(name: "fn5", linkageName: "_Z3fn5v", line: 13, isLocal: false, isDefinition: true, flags: DIFlagPrototyped, isOptimized: true, unit: !0, scopeLine: 13, file: !5, scope: !16, type: !22, variables: !2)
 !25 = !{!26, !27}
-!26 = !DIGlobalVariable(name: "a", line: 4, isLocal: false, isDefinition: true, scope: null, file: !16, type: !4)
-!27 = !DIGlobalVariable(name: "b", line: 4, isLocal: false, isDefinition: true, scope: null, file: !16, type: !4)
+!26 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "a", line: 4, isLocal: false, isDefinition: true, scope: null, file: !16, type: !4))
+!27 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "b", line: 4, isLocal: false, isDefinition: true, scope: null, file: !16, type: !4))
 !28 = !{i32 2, !"Dwarf Version", i32 4}
 !29 = !{i32 2, !"Debug Info Version", i32 3}
 !30 = !{!"clang version 3.7.0 (trunk 227480) (llvm/trunk 227517)"}
diff --git a/llvm/test/Transforms/LoopVectorize/dbg.value.ll b/llvm/test/Transforms/LoopVectorize/dbg.value.ll
index c5ad195d5ca..b780f366ee4 100644
--- a/llvm/test/Transforms/LoopVectorize/dbg.value.ll
+++ b/llvm/test/Transforms/LoopVectorize/dbg.value.ll
@@ -54,12 +54,12 @@ attributes #1 = { nounwind readnone }
 !9 = !DILocalVariable(name: "i", line: 6, scope: !10, file: !4, type: !7)
 !10 = distinct !DILexicalBlock(line: 6, column: 0, file: !25, scope: !3)
 !11 = !{!12, !16, !17}
-!12 = !DIGlobalVariable(name: "A", line: 1, isLocal: false, isDefinition: true, scope: null, file: !4, type: !13)
+!12 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "A", line: 1, isLocal: false, isDefinition: true, scope: null, file: !4, type: !13))
 !13 = !DICompositeType(tag: DW_TAG_array_type, size: 32768, align: 32, baseType: !7, elements: !14)
 !14 = !{!15}
 !15 = !{i32 786465, i64 0, i64 1024}
-!16 = !DIGlobalVariable(name: "B", line: 2, isLocal: false, isDefinition: true, scope: null, file: !4, type: !13)
-!17 = !DIGlobalVariable(name: "C", line: 3, isLocal: false, isDefinition: true, scope: null, file: !4, type: !13)
+!16 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "B", line: 2, isLocal: false, isDefinition: true, scope: null, file: !4, type: !13))
+!17 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "C", line: 3, isLocal: false, isDefinition: true, scope: null, file: !4, type: !13))
 !18 = !DILocation(line: 6, scope: !10)
 !19 = !DILocation(line: 7, scope: !20)
 !20 = distinct !DILexicalBlock(line: 6, column: 0, file: !25, scope: !10)
diff --git a/llvm/test/Transforms/SampleProfile/cov-zero-samples.ll b/llvm/test/Transforms/SampleProfile/cov-zero-samples.ll
index 9ffa8ca36ee..9ec87ef1eb7 100644
--- a/llvm/test/Transforms/SampleProfile/cov-zero-samples.ll
+++ b/llvm/test/Transforms/SampleProfile/cov-zero-samples.ll
@@ -98,7 +98,7 @@ declare i32 @printf(i8*, ...)
 !9 = !DISubroutineType(types: !10)
 !10 = !{!7}
 !11 = !{!12}
-!12 = !DIGlobalVariable(name: "N", scope: !0, file: !1, line: 3, type: !13, isLocal: false, isDefinition: true)
+!12 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "N", scope: !0, file: !1, line: 3, type: !13, isLocal: false, isDefinition: true))
 !13 = !DIDerivedType(tag: DW_TAG_volatile_type, baseType: !14)
 !14 = !DIBasicType(name: "long long int", size: 64, align: 64, encoding: DW_ATE_signed)
 !15 = !{i32 2, !"Dwarf Version", i32 4}
diff --git a/llvm/test/Transforms/SimplifyCFG/PR27615-simplify-cond-br.ll b/llvm/test/Transforms/SimplifyCFG/PR27615-simplify-cond-br.ll
index 94e32dedb61..d2da83963b3 100644
--- a/llvm/test/Transforms/SimplifyCFG/PR27615-simplify-cond-br.ll
+++ b/llvm/test/Transforms/SimplifyCFG/PR27615-simplify-cond-br.ll
@@ -46,13 +46,13 @@ declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #4
 !1 = !DIFile(filename: "csmith107.i.c", directory: "/tmp")
 !2 = !{}
 !3 = !{!4, !6, !10}
-!4 = !DIGlobalVariable(name: "a", scope: null, file: !1, line: 2, type: !5, isLocal: false, isDefinition: true)
+!4 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "a", scope: null, file: !1, line: 2, type: !5, isLocal: false, isDefinition: true))
 !5 = !DIBasicType(name: "int", size: 16, align: 16, encoding: DW_ATE_signed)
-!6 = !DIGlobalVariable(name: "b", scope: null, file: !1, line: 3, type: !7, isLocal: false, isDefinition: true)
+!6 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "b", scope: null, file: !1, line: 3, type: !7, isLocal: false, isDefinition: true))
 !7 = !DIDerivedType(tag: DW_TAG_typedef, name: "uint32_t", file: !1, line: 1, baseType: !8)
 !8 = !DIDerivedType(tag: DW_TAG_typedef, name: "__u32_t", file: !1, baseType: !9)
 !9 = !DIBasicType(name: "unsigned long", size: 32, align: 16, encoding: DW_ATE_unsigned)
-!10 = !DIGlobalVariable(name: "c", scope: null, file: !1, line: 4, type: !11, isLocal: false, isDefinition: true)
+!10 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "c", scope: null, file: !1, line: 4, type: !11, isLocal: false, isDefinition: true))
 !11 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !5, size: 16, align: 16)
 !12 = !{i32 2, !"Dwarf Version", i32 4}
 !13 = !{i32 2, !"Debug Info Version", i32 3}
diff --git a/llvm/test/Transforms/StripSymbols/2010-06-30-StripDebug.ll b/llvm/test/Transforms/StripSymbols/2010-06-30-StripDebug.ll
index 0d08627907d..463064a6cdd 100644
--- a/llvm/test/Transforms/StripSymbols/2010-06-30-StripDebug.ll
+++ b/llvm/test/Transforms/StripSymbols/2010-06-30-StripDebug.ll
@@ -23,7 +23,7 @@ declare void @llvm.dbg.value(metadata, i64, metadata, metadata) nounwind readnon
 !5 = !DILocalVariable(name: "y", line: 3, scope: !6, file: !1, type: !7)
 !6 = distinct !DILexicalBlock(line: 2, column: 0, file: !12, scope: !0)
 !7 = !DIBasicType(tag: DW_TAG_base_type, name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
-!8 = !DIGlobalVariable(name: "x", line: 1, isLocal: false, isDefinition: true, scope: !1, file: !1, type: !7)
+!8 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "x", line: 1, isLocal: false, isDefinition: true, scope: !1, file: !1, type: !7))
 !9 = !{i32 0}
 !10 = !DILocation(line: 3, scope: !6)
 !11 = !DILocation(line: 4, scope: !6)
diff --git a/llvm/test/Transforms/StripSymbols/2010-08-25-crash.ll b/llvm/test/Transforms/StripSymbols/2010-08-25-crash.ll
index 4e454ba2c8b..69e4f261633 100644
--- a/llvm/test/Transforms/StripSymbols/2010-08-25-crash.ll
+++ b/llvm/test/Transforms/StripSymbols/2010-08-25-crash.ll
@@ -13,7 +13,7 @@ entry:
 !3 = !DISubroutineType(types: !4)
 !4 = !{!5}
 !5 = !DIBasicType(tag: DW_TAG_base_type, name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
-!6 = !DIGlobalVariable(name: "i", linkageName: "i", line: 2, isLocal: true, isDefinition: true, scope: !1, file: !1, type: !7)
+!6 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "i", linkageName: "i", line: 2, isLocal: true, isDefinition: true, scope: !1, file: !1, type: !7))
 !7 = !DIDerivedType(tag: DW_TAG_const_type, file: !10, scope: !1, baseType: !5)
 !8 = !DILocation(line: 3, column: 13, scope: !9)
 !9 = distinct !DILexicalBlock(line: 3, column: 11, file: !10, scope: !0)
diff --git a/llvm/test/Transforms/StripSymbols/strip-dead-debug-info.ll b/llvm/test/Transforms/StripSymbols/strip-dead-debug-info.ll
index 2116db49d00..a29427ecf86 100644
--- a/llvm/test/Transforms/StripSymbols/strip-dead-debug-info.ll
+++ b/llvm/test/Transforms/StripSymbols/strip-dead-debug-info.ll
@@ -46,8 +46,8 @@ attributes #2 = { nounwind readonly ssp }
 !13 = !DILocalVariable(name: "bb", line: 5, scope: !14, file: !5, type: !9)
 !14 = distinct !DILexicalBlock(line: 5, column: 0, file: !1, scope: !3)
 !15 = !DILocalVariable(name: "i", line: 7, arg: 1, scope: !10, file: !5, type: !9)
-!16 = !DIGlobalVariable(name: "abcd", line: 2, isLocal: true, isDefinition: true, scope: !5, file: !5, type: !9)
-!17 = !DIGlobalVariable(name: "xyz", line: 3, isLocal: false, isDefinition: true, scope: !5, file: !5, type: !9)
+!16 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "abcd", line: 2, isLocal: true, isDefinition: true, scope: !5, file: !5, type: !9))
+!17 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "xyz", line: 3, isLocal: false, isDefinition: true, scope: !5, file: !5, type: !9))
 !18 = !DILocation(line: 6, scope: !19)
 !19 = distinct !DILexicalBlock(line: 6, column: 0, file: !1, scope: !6)
 !20 = !DILocation(line: 7, scope: !10)
diff --git a/llvm/test/Transforms/Util/strip-nonlinetable-debuginfo-containingtypes.ll b/llvm/test/Transforms/Util/strip-nonlinetable-debuginfo-containingtypes.ll
index 6c6b4996bfe..f21710a1b12 100644
--- a/llvm/test/Transforms/Util/strip-nonlinetable-debuginfo-containingtypes.ll
+++ b/llvm/test/Transforms/Util/strip-nonlinetable-debuginfo-containingtypes.ll
@@ -51,7 +51,7 @@ attributes #2 = { nounwind }
 
 ; CHECK-NEG-NOT: !DI{{Basic|Composite|Derived}}Type
 
-!0 = distinct !DIGlobalVariable(name: "b", scope: !1, file: !2, line: 5, type: !5, isLocal: false, isDefinition: true)
+!0 = distinct !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "b", scope: !1, file: !2, line: 5, type: !5, isLocal: false, isDefinition: true))
 !1 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !2, producer: "clang version 4.0.0 (trunk 282583) (llvm/trunk 282611)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !3, globals: !4)
 !2 = !DIFile(filename: "t.cpp", directory: "/")
 !3 = !{}