Make the default triple optional by allowing an empty string

When building LLVM as a (potentially dynamic) library that can be linked against
by multiple compilers, the default triple is not really meaningful.
We allow to explicitely set it to an empty string when configuring LLVM.
In this case, said "target independent" tests in the test suite that are using
the default triple are disabled by matching the newly available feature
"default_triple".

Reviewers: probinson, echristo
Differential Revision: http://reviews.llvm.org/D12660

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 247775

1 files changed, 114 insertions, 0 deletions

diff --git a/llvm/test/DebugInfo/Generic/gvn.ll b/llvm/test/DebugInfo/Generic/gvn.ll
new file mode 100644
index 00000000000..1b32918dd34
--- /dev/null
+++ b/llvm/test/DebugInfo/Generic/gvn.ll
@@ -0,0 +1,114 @@
+; RUN: opt < %s -gvn -S | FileCheck %s
+;
+; Produced at -O2 from:
+; int a, b;
+; void f1(int *p1) {
+;   if (b)
+;     a = 1;
+;   if (a && *p1)
+;     f4();
+; }
+; int f2(int);
+; void f3(void) {
+;   a = f2(1);
+;   f1(&a);
+; }
+target datalayout = "e-m:o-i64:64-i128:128-n32:64-S128"
+target triple = "arm64-apple-ios"
+
+@a = common global i32 0, align 4
+@b = common global i32 0, align 4
+
+; Function Attrs: nounwind
+define void @f3() #0 {
+entry:
+  ; Verify that the call still has a debug location after GVN.
+  ; CHECK: %call = tail call i32 @f2(i32 1) #{{[0-9]}}, !dbg
+  %call = tail call i32 @f2(i32 1) #3, !dbg !36
+  store i32 %call, i32* @a, align 4, !dbg !36, !tbaa !25
+  tail call void @llvm.dbg.value(metadata i32* @a, i64 0, metadata !11, metadata !21) #3, !dbg !39
+  %0 = load i32, i32* @b, align 4, !dbg !39, !tbaa !25
+  %tobool.i = icmp eq i32 %0, 0, !dbg !39
+  br i1 %tobool.i, label %if.end.i, label %land.lhs.true.i.thread, !dbg !40
+
+land.lhs.true.i.thread:                           ; preds = %entry
+  store i32 1, i32* @a, align 4, !dbg !41, !tbaa !25
+  br label %if.then.3.i, !dbg !42
+
+if.end.i:                                         ; preds = %entry
+  ; This instruction has no debug location -- in this
+  ; particular case it was removed by a bug in SimplifyCFG.
+  %.pr = load i32, i32* @a, align 4
+
+  ; GVN is supposed to replace the load of %.pr with a direct reference to %call.
+  ; CHECK: %tobool2.i = icmp eq i32 %call, 0, !dbg
+  %tobool2.i = icmp eq i32 %.pr, 0, !dbg !43
+  br i1 %tobool2.i, label %f1.exit, label %if.then.3.i, !dbg !43
+
+if.then.3.i:                                      ; preds = %if.end.i, %land.lhs.true.i.thread
+  %call.i = tail call i32 bitcast (i32 (...)* @f4 to i32 ()*)() #3, !dbg !44
+  br label %f1.exit, !dbg !44
+
+f1.exit:                                          ; preds = %if.end.i, %if.then.3.i
+  ret void, !dbg !45
+}
+
+declare i32 @f2(i32)
+declare i32 @f4(...)
+
+; Function Attrs: nounwind readnone
+declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #2
+
+attributes #0 = { nounwind }
+attributes #2 = { nounwind readnone }
+attributes #3 = { nounwind }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!18, !19}
+!llvm.ident = !{!20}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 3.8.0 (trunk 245562) (llvm/trunk 245569)", isOptimized: true, runtimeVersion: 0, emissionKind: 1, enums: !2, subprograms: !3, globals: !15)
+!1 = !DIFile(filename: "test.c", directory: "/")
+!2 = !{}
+!3 = !{!4, !12}
+!4 = distinct !DISubprogram(name: "f1", scope: !1, file: !1, line: 2, type: !6, isLocal: false, isDefinition: true, scopeLine: 2, flags: DIFlagPrototyped, isOptimized: true, variables: !10)
+!6 = !DISubroutineType(types: !7)
+!7 = !{null, !8}
+!8 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !9, size: 64, align: 64)
+!9 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
+!10 = !{!11}
+!11 = !DILocalVariable(name: "p1", arg: 1, scope: !4, file: !1, line: 2, type: !8)
+!12 = distinct !DISubprogram(name: "f3", scope: !1, file: !1, line: 9, type: !13, isLocal: false, isDefinition: true, scopeLine: 9, flags: DIFlagPrototyped, isOptimized: true, function: void ()* @f3, variables: !2)
+!13 = !DISubroutineType(types: !14)
+!14 = !{null}
+!15 = !{!16, !17}
+!16 = !DIGlobalVariable(name: "a", scope: !0, file: !1, line: 1, type: !9, isLocal: false, isDefinition: true, variable: i32* @a)
+!17 = !DIGlobalVariable(name: "b", scope: !0, file: !1, line: 1, type: !9, isLocal: false, isDefinition: true, variable: i32* @b)
+!18 = !{i32 2, !"Dwarf Version", i32 2}
+!19 = !{i32 2, !"Debug Info Version", i32 3}
+!20 = !{!"clang version 3.8.0 (trunk 245562) (llvm/trunk 245569)"}
+!21 = !DIExpression()
+!22 = !DILocation(line: 2, scope: !4)
+!23 = !DILocation(line: 3, scope: !24)
+!24 = distinct !DILexicalBlock(scope: !4, file: !1, line: 3)
+!25 = !{!26, !26, i64 0}
+!26 = !{!"int", !27, i64 0}
+!27 = !{!"omnipotent char", !28, i64 0}
+!28 = !{!"Simple C/C++ TBAA"}
+!29 = !DILocation(line: 3, scope: !4)
+!30 = !DILocation(line: 4, scope: !24)
+!31 = !DILocation(line: 5, scope: !32)
+!32 = distinct !DILexicalBlock(scope: !4, file: !1, line: 5)
+!33 = !DILocation(line: 5, scope: !4)
+!34 = !DILocation(line: 6, scope: !32)
+!35 = !DILocation(line: 7, scope: !4)
+!36 = !DILocation(line: 5, scope: !32, inlinedAt: !37)
+!37 = distinct !DILocation(line: 11, scope: !12)
+!38 = !DILocation(line: 10, scope: !12)
+!39 = !DILocation(line: 2, scope: !4, inlinedAt: !37)
+!40 = !DILocation(line: 3, scope: !24, inlinedAt: !37)
+!41 = !DILocation(line: 3, scope: !4, inlinedAt: !37)
+!42 = !DILocation(line: 4, scope: !24, inlinedAt: !37)
+!43 = !DILocation(line: 5, scope: !4, inlinedAt: !37)
+!44 = !DILocation(line: 6, scope: !32, inlinedAt: !37)
+!45 = !DILocation(line: 12, scope: !12)