Preserve debug info attached with call instruction while eliminating dead argument.

Radar 7927803

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102760 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/IPO/DeadArgumentElimination.cpp b/lib/Transforms/IPO/DeadArgumentElimination.cpp
index 191c62a3f666e6cd591ebc1070ba2d399d9776fa..6443dd4f47a65be7800d60c5179568ca0afeb995 100644 (file)
--- a/lib/Transforms/IPO/DeadArgumentElimination.cpp
+++ b/lib/Transforms/IPO/DeadArgumentElimination.cpp
@@ -243,6 +243,9 @@ bool DAE::DeleteDeadVarargs(Function &Fn) {
       if (cast<CallInst>(Call)->isTailCall())
         cast<CallInst>(New)->setTailCall();
     }
+    if (MDNode *N = Call->getDbgMetadata())
+      New->setDbgMetadata(N);
+
     Args.clear();
 
     if (!Call->use_empty())
@@ -770,6 +773,9 @@ bool DAE::RemoveDeadStuffFromFunction(Function *F) {
       if (cast<CallInst>(Call)->isTailCall())
         cast<CallInst>(New)->setTailCall();
     }
+    if (MDNode *N = Call->getDbgMetadata())
+      New->setDbgMetadata(N);
+
     Args.clear();
 
     if (!Call->use_empty()) {

diff --git a/test/Transforms/DeadArgElim/2010-04-30-DbgInfo.ll b/test/Transforms/DeadArgElim/2010-04-30-DbgInfo.ll
new file mode 100644 (file)
index 0000000..2f820ba
--- /dev/null
+++ b/test/Transforms/DeadArgElim/2010-04-30-DbgInfo.ll
@@ -0,0 +1,68 @@
+; RUN: opt -S -deadargelim < %s | FileCheck %s
+
+@.str = private constant [1 x i8] zeroinitializer, align 1 ; <[1 x i8]*> [#uses=1]
+
+define i8* @vfs_addname(i8* %name, i32 %len, i32 %hash, i32 %flags) nounwind ssp {
+entry:
+  call void @llvm.dbg.value(metadata !{i8* %name}, i64 0, metadata !0)
+  call void @llvm.dbg.value(metadata !{i32 %len}, i64 0, metadata !10)
+  call void @llvm.dbg.value(metadata !{i32 %hash}, i64 0, metadata !11)
+  call void @llvm.dbg.value(metadata !{i32 %flags}, i64 0, metadata !12)
+; CHECK:  call fastcc i8* @add_name_internal(i8* %name, i32 %hash) nounwind, !dbg !13
+  %0 = call fastcc i8* @add_name_internal(i8* %name, i32 %len, i32 %hash, i8 zeroext 0, i32 %flags) nounwind, !dbg !13 ; <i8*> [#uses=1]
+  ret i8* %0, !dbg !13
+}
+
+declare void @llvm.dbg.declare(metadata, metadata) nounwind readnone
+
+define internal fastcc i8* @add_name_internal(i8* %name, i32 %len, i32 %hash, i8 zeroext %extra, i32 %flags) nounwind noinline ssp {
+entry:
+  call void @llvm.dbg.value(metadata !{i8* %name}, i64 0, metadata !15)
+  call void @llvm.dbg.value(metadata !{i32 %len}, i64 0, metadata !20)
+  call void @llvm.dbg.value(metadata !{i32 %hash}, i64 0, metadata !21)
+  call void @llvm.dbg.value(metadata !{i8 %extra}, i64 0, metadata !22)
+  call void @llvm.dbg.value(metadata !{i32 %flags}, i64 0, metadata !23)
+  %0 = icmp eq i32 %hash, 0, !dbg !24             ; <i1> [#uses=1]
+  br i1 %0, label %bb, label %bb1, !dbg !24
+
+bb:                                               ; preds = %entry
+  br label %bb2, !dbg !26
+
+bb1:                                              ; preds = %entry
+  br label %bb2, !dbg !27
+
+bb2:                                              ; preds = %bb1, %bb
+  %.0 = phi i8* [ getelementptr inbounds ([1 x i8]* @.str, i64 0, i64 0), %bb ], [ %name, %bb1 ] ; <i8*> [#uses=1]
+  ret i8* %.0, !dbg !27
+}
+
+declare void @llvm.dbg.value(metadata, i64, metadata) nounwind readnone
+
+!0 = metadata !{i32 524545, metadata !1, metadata !"name", metadata !2, i32 8, metadata !6} ; [ DW_TAG_arg_variable ]
+!1 = metadata !{i32 524334, i32 0, metadata !2, metadata !"vfs_addname", metadata !"vfs_addname", metadata !"vfs_addname", metadata !2, i32 12, metadata !4, i1 false, i1 true, i32 0, i32 0, null, i1 false} ; [ DW_TAG_subprogram ]
+!2 = metadata !{i32 524329, metadata !"tail.c", metadata !"/Users/echeng/LLVM/radars/r7927803/", metadata !3} ; [ DW_TAG_file_type ]
+!3 = metadata !{i32 524305, i32 0, i32 1, metadata !"tail.c", metadata !"/Users/echeng/LLVM/radars/r7927803/", metadata !"4.2.1 (Based on Apple Inc. build 5658) (LLVM build 9999)", i1 true, i1 false, metadata !"", i32 0} ; [ DW_TAG_compile_unit ]
+!4 = metadata !{i32 524309, metadata !2, metadata !"", metadata !2, i32 0, i64 0, i64 0, i64 0, i32 0, null, metadata !5, i32 0, null} ; [ DW_TAG_subroutine_type ]
+!5 = metadata !{metadata !6, metadata !6, metadata !9, metadata !9, metadata !9}
+!6 = metadata !{i32 524303, metadata !2, metadata !"", metadata !2, i32 0, i64 64, i64 64, i64 0, i32 0, metadata !7} ; [ DW_TAG_pointer_type ]
+!7 = metadata !{i32 524326, metadata !2, metadata !"", metadata !2, i32 0, i64 8, i64 8, i64 0, i32 0, metadata !8} ; [ DW_TAG_const_type ]
+!8 = metadata !{i32 524324, metadata !2, metadata !"char", metadata !2, i32 0, i64 8, i64 8, i64 0, i32 0, i32 6} ; [ DW_TAG_base_type ]
+!9 = metadata !{i32 524324, metadata !2, metadata !"unsigned int", metadata !2, i32 0, i64 32, i64 32, i64 0, i32 0, i32 7} ; [ DW_TAG_base_type ]
+!10 = metadata !{i32 524545, metadata !1, metadata !"len", metadata !2, i32 9, metadata !9} ; [ DW_TAG_arg_variable ]
+!11 = metadata !{i32 524545, metadata !1, metadata !"hash", metadata !2, i32 10, metadata !9} ; [ DW_TAG_arg_variable ]
+!12 = metadata !{i32 524545, metadata !1, metadata !"flags", metadata !2, i32 11, metadata !9} ; [ DW_TAG_arg_variable ]
+!13 = metadata !{i32 13, i32 0, metadata !14, null}
+!14 = metadata !{i32 524299, metadata !1, i32 12, i32 0} ; [ DW_TAG_lexical_block ]
+!15 = metadata !{i32 524545, metadata !16, metadata !"name", metadata !2, i32 17, metadata !6} ; [ DW_TAG_arg_variable ]
+!16 = metadata !{i32 524334, i32 0, metadata !2, metadata !"add_name_internal", metadata !"add_name_internal", metadata !"add_name_internal", metadata !2, i32 22, metadata !17, i1 true, i1 true, i32 0, i32 0, null, i1 false} ; [ DW_TAG_subprogram ]
+!17 = metadata !{i32 524309, metadata !2, metadata !"", metadata !2, i32 0, i64 0, i64 0, i64 0, i32 0, null, metadata !18, i32 0, null} ; [ DW_TAG_subroutine_type ]
+!18 = metadata !{metadata !6, metadata !6, metadata !9, metadata !9, metadata !19, metadata !9}
+!19 = metadata !{i32 524324, metadata !2, metadata !"unsigned char", metadata !2, i32 0, i64 8, i64 8, i64 0, i32 0, i32 8} ; [ DW_TAG_base_type ]
+!20 = metadata !{i32 524545, metadata !16, metadata !"len", metadata !2, i32 18, metadata !9} ; [ DW_TAG_arg_variable ]
+!21 = metadata !{i32 524545, metadata !16, metadata !"hash", metadata !2, i32 19, metadata !9} ; [ DW_TAG_arg_variable ]
+!22 = metadata !{i32 524545, metadata !16, metadata !"extra", metadata !2, i32 20, metadata !19} ; [ DW_TAG_arg_variable ]
+!23 = metadata !{i32 524545, metadata !16, metadata !"flags", metadata !2, i32 21, metadata !9} ; [ DW_TAG_arg_variable ]
+!24 = metadata !{i32 23, i32 0, metadata !25, null}
+!25 = metadata !{i32 524299, metadata !16, i32 22, i32 0} ; [ DW_TAG_lexical_block ]
+!26 = metadata !{i32 24, i32 0, metadata !25, null}
+!27 = metadata !{i32 26, i32 0, metadata !25, null}