DI: Reverse direction of subprogram -> function edge.
Previously, subprograms contained a metadata reference to the function they
described. Because most clients need to get or set a subprogram for a given
function rather than the other way around, this created unneeded inefficiency.
For example, many passes needed to call the function llvm::makeSubprogramMap()
to build a mapping from functions to subprograms, and the IR linker needed to
fix up function references in a way that caused quadratic complexity in the IR
linking phase of LTO.
This change reverses the direction of the edge by storing the subprogram as
function-level metadata and removing DISubprogram's function field.
Since this is an IR change, a bitcode upgrade has been provided.
Fixes PR23367. An upgrade script for textual IR for out-of-tree clients is
attached to the PR.
Differential Revision: http://reviews.llvm.org/D14265
llvm-svn: 252219
diff --git a/llvm/test/Transforms/SampleProfile/gcc-simple.ll b/llvm/test/Transforms/SampleProfile/gcc-simple.ll
index 75d54bf..1ae9271 100644
--- a/llvm/test/Transforms/SampleProfile/gcc-simple.ll
+++ b/llvm/test/Transforms/SampleProfile/gcc-simple.ll
@@ -24,7 +24,7 @@
; $ perf record -b ./gcc-simple
; $ create_gcov --binary=gcc-simple --gcov=gcc-simple.afdo
-define i64 @_Z3fool(i64 %i) #0 {
+define i64 @_Z3fool(i64 %i) #0 !dbg !4 {
; CHECK: !prof ![[EC1:[0-9]+]]
entry:
%retval = alloca i64, align 8
@@ -66,7 +66,7 @@
declare i32 @rand() #2
; Function Attrs: nounwind uwtable
-define i32 @main() #0 {
+define i32 @main() #0 !dbg !9 {
; CHECK: !prof ![[EC2:[0-9]+]]
entry:
%retval = alloca i32, align 4
@@ -148,12 +148,12 @@
!1 = !DIFile(filename: "discriminator.cc", directory: "/usr/local/google/home/dnovillo/llvm/test/autofdo")
!2 = !{}
!3 = !{!4, !9}
-!4 = distinct !DISubprogram(name: "foo", linkageName: "_Z3fool", scope: !1, file: !1, line: 3, type: !5, isLocal: false, isDefinition: true, scopeLine: 3, flags: DIFlagPrototyped, isOptimized: false, function: i64 (i64)* @_Z3fool, variables: !2)
+!4 = distinct !DISubprogram(name: "foo", linkageName: "_Z3fool", scope: !1, file: !1, line: 3, type: !5, isLocal: false, isDefinition: true, scopeLine: 3, flags: DIFlagPrototyped, isOptimized: false, variables: !2)
!5 = !DISubroutineType(types: !6)
!6 = !{!7, !8}
!7 = !DIBasicType(name: "long long int", size: 64, align: 64, encoding: DW_ATE_signed)
!8 = !DIBasicType(name: "long int", size: 64, align: 64, encoding: DW_ATE_signed)
-!9 = distinct !DISubprogram(name: "main", scope: !1, file: !1, line: 7, type: !10, isLocal: false, isDefinition: true, scopeLine: 7, flags: DIFlagPrototyped, isOptimized: false, function: i32 ()* @main, variables: !2)
+!9 = distinct !DISubprogram(name: "main", scope: !1, file: !1, line: 7, type: !10, isLocal: false, isDefinition: true, scopeLine: 7, flags: DIFlagPrototyped, isOptimized: false, variables: !2)
!10 = !DISubroutineType(types: !11)
!11 = !{!12}
!12 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)