e20b904721
It's useful if the probe-based build can consume a dwarf based profile(e.g. the profile transition), before there is a conflict for the discriminator, this change tries to mitigate the issue by encoding the dwarf base discriminator into the probe discriminator. As the num of probe id(num of basic block and calls) starts from 1, there are some unused space. We try to reuse some bit of the probe id. The new encode rule is: - Use a bit to [28:28] to indicate whether dwarf base discriminator is encoded.(fortunately we can borrow this bit from the `PseudoProbeType`) - If the bit is set, use [15:3] for probe id, [18:16] for dwarf base discriminator. Otherwise, still use [18:3] for probe id. Note that these doesn't affect the original probe id capacity, we still prioritize probe id encoding, i.e. the base discriminator is not encoded when probe id is bigger than [15:3]. Then adjust `getBaseDiscriminatorFromDiscriminator` to use the base discriminator from the probe discriminator.
78 lines
3.4 KiB
LLVM
78 lines
3.4 KiB
LLVM
; REQUIRES: x86_64-linux
|
|
; RUN: opt < %s -passes='pseudo-probe,loop-unroll-full' -verify-pseudo-probe -S -o %t 2>&1 | FileCheck %s --check-prefix=VERIFY
|
|
; RUN: FileCheck %s < %t
|
|
|
|
; VERIFY: *** Pseudo Probe Verification After LoopFullUnrollPass ***
|
|
; VERIFY: Function foo:
|
|
; VERIFY-DAG: Probe 5 previous factor 1.00 current factor 5.00
|
|
; VERIFY-DAG: Probe 4 previous factor 1.00 current factor 5.00
|
|
|
|
declare void @foo2() nounwind
|
|
|
|
define void @foo(i32 %x) {
|
|
bb:
|
|
; CHECK: call void @llvm.pseudoprobe(i64 [[#GUID:]], i64 1, i32 0, i64 -1)
|
|
%tmp = alloca [5 x ptr], align 16
|
|
br label %bb7.preheader
|
|
|
|
bb3.loopexit:
|
|
%spec.select.lcssa = phi i32 [ %spec.select, %bb10 ]
|
|
%tmp5.not = icmp eq i32 %spec.select.lcssa, 0
|
|
br i1 %tmp5.not, label %bb24, label %bb7.preheader
|
|
|
|
bb7.preheader:
|
|
; CHECK: call void @llvm.pseudoprobe(i64 [[#GUID:]], i64 3, i32 0, i64 -1)
|
|
%tmp1.06 = phi i32 [ 5, %bb ], [ %spec.select.lcssa, %bb3.loopexit ]
|
|
br label %bb10
|
|
|
|
bb10:
|
|
; CHECK: call void @llvm.pseudoprobe(i64 [[#GUID:]], i64 4, i32 0, i64 -1)
|
|
; CHECK: call void @foo2(), !dbg ![[#PROBE6:]]
|
|
; CHECK: call void @llvm.pseudoprobe(i64 [[#GUID:]], i64 4, i32 0, i64 -1)
|
|
; CHECK: call void @foo2(), !dbg ![[#PROBE6:]]
|
|
; CHECK: call void @llvm.pseudoprobe(i64 [[#GUID:]], i64 4, i32 0, i64 -1)
|
|
; CHECK: call void @foo2(), !dbg ![[#PROBE6:]]
|
|
; CHECK: call void @llvm.pseudoprobe(i64 [[#GUID:]], i64 4, i32 0, i64 -1)
|
|
; CHECK: call void @foo2(), !dbg ![[#PROBE6:]]
|
|
; CHECK: call void @llvm.pseudoprobe(i64 [[#GUID:]], i64 4, i32 0, i64 -1)
|
|
; CHECK: call void @foo2(), !dbg ![[#PROBE6:]]
|
|
; CHECK: call void @llvm.pseudoprobe(i64 [[#GUID:]], i64 2, i32 0, i64 -1)
|
|
%indvars.iv = phi i64 [ 0, %bb7.preheader ], [ %indvars.iv.next, %bb10 ]
|
|
%tmp1.14 = phi i32 [ %tmp1.06, %bb7.preheader ], [ %spec.select, %bb10 ]
|
|
%tmp13 = getelementptr inbounds [5 x ptr], ptr %tmp, i64 0, i64 %indvars.iv
|
|
%tmp14 = load ptr, ptr %tmp13, align 8
|
|
%tmp15.not = icmp ne ptr %tmp14, null
|
|
%tmp18 = sext i1 %tmp15.not to i32
|
|
%spec.select = add nsw i32 %tmp1.14, %tmp18
|
|
call void @foo2(), !dbg !12
|
|
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
|
|
%exitcond.not = icmp eq i64 %indvars.iv.next, 5
|
|
br i1 %exitcond.not, label %bb3.loopexit, label %bb10, !llvm.loop !13
|
|
|
|
bb24:
|
|
; CHECK: call void @llvm.pseudoprobe(i64 [[#GUID:]], i64 6, i32 0, i64 -1)
|
|
ret void
|
|
}
|
|
|
|
;; A discriminator of 455082031 which is 0x1b200037 in hexdecimal, stands for a direct call probe
|
|
;; with an index of 6 and a scale of -1%.
|
|
; CHECK: ![[#PROBE6]] = !DILocation(line: 2, column: 20, scope: ![[#SCOPE:]])
|
|
; CHECK: ![[#SCOPE]] = !DILexicalBlockFile(scope: ![[#]], file: ![[#]], discriminator: 455082031)
|
|
|
|
!llvm.dbg.cu = !{!0}
|
|
!llvm.module.flags = !{!9, !10}
|
|
|
|
!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 3.9.0", isOptimized: false, runtimeVersion: 0, emissionKind: 1, enums: !2)
|
|
!1 = !DIFile(filename: "test.c", directory: "")
|
|
!2 = !{}
|
|
!4 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 2, type: !5, isLocal: false, isDefinition: true, scopeLine: 2, isOptimized: false, unit: !0, retainedNodes: !2)
|
|
!5 = !DISubroutineType(types: !6)
|
|
!6 = !{!7}
|
|
!7 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
|
|
!9 = !{i32 2, !"Dwarf Version", i32 4}
|
|
!10 = !{i32 2, !"Debug Info Version", i32 3}
|
|
!11 = !{!"clang version 3.9.0"}
|
|
!12 = !DILocation(line: 2, column: 20, scope: !4)
|
|
!13 = distinct !{!13, !14}
|
|
!14 = !{!"llvm.loop.unroll.full"}
|