[InstCombine] Folding loads through a phi node should merge the debug locations
If all the operands to a phi node are a load, instcombine will try to pull
them through the phi node, combining them into a single load. When it does
this, the debug location of the new load should be the merged debug locations
of the phi node arguments.
Patch 5 of 8 for D26256. Folding of a load operation.
Differential Revision: https://reviews.llvm.org/D26256
llvm-svn: 289688
diff --git a/llvm/test/DebugInfo/Generic/instcombine-phi.ll b/llvm/test/DebugInfo/Generic/instcombine-phi.ll
index 49829cb..f72a333 100644
--- a/llvm/test/DebugInfo/Generic/instcombine-phi.ll
+++ b/llvm/test/DebugInfo/Generic/instcombine-phi.ll
@@ -132,10 +132,53 @@
ret i32* %r.0, !dbg !30
}
+; Test folding of load. Generated from source:
+
+; extern int *foo3(void);
+; extern int *bar3(void);
+;
+; int load(int a) {
+; int r;
+; if(a)
+; r = *foo3();
+; else
+; r = *bar3();
+; return r;
+; }
+
+; CHECK: define i32 @load
+; CHECK-LABEL: if.end:
+; CHECK: %[[PHI:.*]] = phi i32* [ %call, %if.then ], [ %call1, %if.else ]
+; CHECK: load i32, i32* %[[PHI]]
+; CHECK-NOT: !dbg
+; CHECK: ret i32
+
+define i32 @load(i32 %a) !dbg !31 {
+entry:
+ %tobool = icmp ne i32 %a, 0, !dbg !32
+ br i1 %tobool, label %if.then, label %if.else, !dbg !32
+
+if.then: ; preds = %entry
+ %call = call i32* @foo3(), !dbg !33
+ %0 = load i32, i32* %call, align 4, !dbg !34
+ br label %if.end, !dbg !35
+
+if.else: ; preds = %entry
+ %call1 = call i32* @bar3(), !dbg !36
+ %1 = load i32, i32* %call1, align 4, !dbg !37
+ br label %if.end
+
+if.end: ; preds = %if.else, %if.then
+ %r.0 = phi i32 [ %0, %if.then ], [ %1, %if.else ]
+ ret i32 %r.0, !dbg !38
+}
+
declare i32 @foo()
declare i32 @bar()
declare i64 @foo2()
declare i64 @bar2()
+declare i32* @foo3()
+declare i32* @bar3()
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!3, !4}
@@ -170,3 +213,11 @@
!28 = !DILocation(line: 30, column: 12, scope: !23)
!29 = !DILocation(line: 30, column: 10, scope: !23)
!30 = !DILocation(line: 31, column: 3, scope: !23)
+!31 = distinct !DISubprogram(name: "load", scope: !1, file: !1, line: 34, type: !7, isLocal: false, isDefinition: true, scopeLine: 34, flags: DIFlagPrototyped, isOptimized: false, unit: !0, variables: !2)
+!32 = !DILocation(line: 36, column: 6, scope: !31)
+!33 = !DILocation(line: 37, column: 10, scope: !31)
+!34 = !DILocation(line: 37, column: 9, scope: !31)
+!35 = !DILocation(line: 37, column: 5, scope: !31)
+!36 = !DILocation(line: 39, column: 10, scope: !31)
+!37 = !DILocation(line: 39, column: 9, scope: !31)
+!38 = !DILocation(line: 40, column: 3, scope: !31)