Reapply: Teach SROA how to update debug info for fragmented variables.

This reapplies r225379.

ChangeLog:
- The assertion that this commit previously ran into about the inability
  to handle indirect variables has since been removed and the backend
  can handle this now.
- Testcases were upgrade to the new MDLocation format.
- Instead of keeping a DebugDeclares map, we now use
  llvm::FindAllocaDbgDeclare().

Original commit message follows.

Debug info: Teach SROA how to update debug info for fragmented variables.
This allows us to generate debug info for extremely advanced code such as

 typedef struct { long int a; int b;} S;

 int foo(S s) {
   return s.b;
 }

which at -O1 on x86_64 is codegen'd into

 define i32 @foo(i64 %s.coerce0, i32 %s.coerce1) #0 {
   ret i32 %s.coerce1, !dbg !24
 }

with this patch we emit the following debug info for this

 TAG_formal_parameter [3]
   AT_location( 0x00000000
                0x0000000000000000 - 0x0000000000000006: rdi, piece 0x00000008, rsi, piece 0x00000004
                0x0000000000000006 - 0x0000000000000008: rdi, piece 0x00000008, rax, piece 0x00000004 )
                AT_name( "s" )
                AT_decl_file( "/Volumes/Data/llvm/_build.ninja.release/test.c" )

Thanks to chandlerc, dblaikie, and echristo for their feedback on all
previous iterations of this patch!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226598 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Adrian Prantl 2015-01-20 19:42:22 +00:00
parent 46846844ee
commit a65da70a54
5 changed files with 316 additions and 12 deletions

View File

@ -1257,8 +1257,8 @@ private:
friend class AllocaSliceRewriter;
bool presplitLoadsAndStores(AllocaInst &AI, AllocaSlices &AS);
bool rewritePartition(AllocaInst &AI, AllocaSlices &AS,
AllocaSlices::Partition &P);
AllocaInst *rewritePartition(AllocaInst &AI, AllocaSlices &AS,
AllocaSlices::Partition &P);
bool splitAlloca(AllocaInst &AI, AllocaSlices &AS);
bool runOnAlloca(AllocaInst &AI);
void clobberUse(Use &U);
@ -3964,8 +3964,8 @@ bool SROA::presplitLoadsAndStores(AllocaInst &AI, AllocaSlices &AS) {
/// appropriate new offsets. It also evaluates how successful the rewrite was
/// at enabling promotion and if it was successful queues the alloca to be
/// promoted.
bool SROA::rewritePartition(AllocaInst &AI, AllocaSlices &AS,
AllocaSlices::Partition &P) {
AllocaInst *SROA::rewritePartition(AllocaInst &AI, AllocaSlices &AS,
AllocaSlices::Partition &P) {
// Try to compute a friendly type for this partition of the alloca. This
// won't always succeed, in which case we fall back to a legal integer type
// or an i8 array of an appropriate size.
@ -4003,6 +4003,7 @@ bool SROA::rewritePartition(AllocaInst &AI, AllocaSlices &AS,
NewAI = &AI;
// FIXME: We should be able to bail at this point with "nothing changed".
// FIXME: We might want to defer PHI speculation until after here.
// FIXME: return nullptr;
} else {
unsigned Alignment = AI.getAlignment();
if (!Alignment) {
@ -4098,7 +4099,7 @@ bool SROA::rewritePartition(AllocaInst &AI, AllocaSlices &AS,
PostPromotionWorklist.pop_back();
}
return true;
return NewAI;
}
/// \brief Walks the slices of an alloca and form partitions based on them,
@ -4137,9 +4138,24 @@ bool SROA::splitAlloca(AllocaInst &AI, AllocaSlices &AS) {
if (!IsSorted)
std::sort(AS.begin(), AS.end());
/// \brief Describes the allocas introduced by rewritePartition
/// in order to migrate the debug info.
struct Piece {
AllocaInst *Alloca;
uint64_t Offset;
uint64_t Size;
Piece(AllocaInst *AI, uint64_t O, uint64_t S)
: Alloca(AI), Offset(O), Size(S) {}
};
SmallVector<Piece, 4> Pieces;
// Rewrite each partition.
for (auto &P : AS.partitions()) {
Changed |= rewritePartition(AI, AS, P);
if (AllocaInst *NewAI = rewritePartition(AI, AS, P)) {
Changed = true;
if (NewAI != &AI)
Pieces.push_back(Piece(NewAI, P.beginOffset(), P.size()));
}
++NumPartitions;
}
@ -4147,6 +4163,28 @@ bool SROA::splitAlloca(AllocaInst &AI, AllocaSlices &AS) {
MaxPartitionsPerAlloca =
std::max<unsigned>(NumPartitions, MaxPartitionsPerAlloca);
// Migrate debug information from the old alloca to the new alloca(s)
// and the individial partitions.
if (DbgDeclareInst *DbgDecl = FindAllocaDbgDeclare(&AI)) {
DIVariable Var(DbgDecl->getVariable());
DIExpression Expr(DbgDecl->getExpression());
DIBuilder DIB(*AI.getParent()->getParent()->getParent(),
/*AllowUnresolved*/ false);
bool IsSplit = Pieces.size() > 1;
for (auto Piece : Pieces) {
// Create a piece expression describing the new partition or reuse AI's
// expression if there is only one partition.
if (IsSplit)
Expr = DIB.createPieceExpression(Piece.Offset, Piece.Size);
// Remove any existing dbg.declare intrinsic describing the same alloca.
if (DbgDeclareInst *OldDDI = FindAllocaDbgDeclare(Piece.Alloca))
OldDDI->eraseFromParent();
Instruction *NewDDI = DIB.insertDeclare(Piece.Alloca, Var, Expr, &AI);
NewDDI->setDebugLoc(DbgDecl->getDebugLoc());
}
}
return Changed;
}
@ -4258,8 +4296,11 @@ void SROA::deleteDeadInstructions(
DeadInsts.insert(U);
}
if (AllocaInst *AI = dyn_cast<AllocaInst>(I))
if (AllocaInst *AI = dyn_cast<AllocaInst>(I)) {
DeletedAllocas.insert(AI);
if (DbgDeclareInst *DbgDecl = FindAllocaDbgDeclare(AI))
DbgDecl->eraseFromParent();
}
++NumDeleted;
I->eraseFromParent();
@ -4376,9 +4417,10 @@ bool SROA::runOnFunction(Function &F) {
BasicBlock &EntryBB = F.getEntryBlock();
for (BasicBlock::iterator I = EntryBB.begin(), E = std::prev(EntryBB.end());
I != E; ++I)
I != E; ++I) {
if (AllocaInst *AI = dyn_cast<AllocaInst>(I))
Worklist.insert(AI);
}
bool Changed = false;
// A set of deleted alloca instruction pointers which should be removed from

View File

@ -13,12 +13,12 @@
; }
;
; RUN: opt %s -O2 -S -o - | FileCheck %s
; Test that we do not lower dbg.declares for arrays.
; Test that we correctly lower dbg.declares for arrays.
;
; CHECK: define i32 @main
; CHECK: call void @llvm.dbg.value
; CHECK: call void @llvm.dbg.value
; CHECK: call void @llvm.dbg.declare
; CHECK: call void @llvm.dbg.value(metadata i32 42, i64 0, metadata ![[ARRAY:[0-9]+]], metadata ![[EXPR:[0-9]+]])
; CHECK: ![[ARRAY]] = {{.*}}; [ DW_TAG_auto_variable ] [array] [line 6]
; CHECK: ![[EXPR]] = {{.*}}; [ DW_TAG_expression ] [DW_OP_piece offset=0, size=4]
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.9.0"

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@ -0,0 +1,97 @@
; RUN: opt %s -sroa -verify -S -o - | FileCheck %s
;
; Test that we can partial emit debug info for aggregates repeatedly
; split up by SROA.
;
; // Compile with -O1
; typedef struct {
; int a;
; long int b;
; } Inner;
;
; typedef struct {
; Inner inner[2];
; } Outer;
;
; int foo(Outer outer) {
; Inner i1 = outer.inner[1];
; return i1.a;
; }
;
; Verify that SROA creates a variable piece when splitting i1.
; CHECK: %[[I1:.*]] = alloca [12 x i8], align 4
; CHECK: call void @llvm.dbg.declare(metadata [12 x i8]* %[[I1]], metadata ![[VAR:[0-9]+]], metadata ![[PIECE1:[0-9]+]])
; CHECK: call void @llvm.dbg.value(metadata i32 %[[A:.*]], i64 0, metadata ![[VAR]], metadata ![[PIECE2:[0-9]+]])
; CHECK: ret i32 %[[A]]
; Read Var and Piece:
; CHECK: ![[VAR]] = {{.*}} ; [ DW_TAG_auto_variable ] [i1] [line 11]
; CHECK: ![[PIECE1]] = {{.*}} ; [ DW_TAG_expression ] [DW_OP_piece offset=4, size=12]
; CHECK: ![[PIECE2]] = {{.*}} ; [ DW_TAG_expression ] [DW_OP_piece offset=0, size=4]
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.9.0"
%struct.Outer = type { [2 x %struct.Inner] }
%struct.Inner = type { i32, i64 }
; Function Attrs: nounwind ssp uwtable
define i32 @foo(%struct.Outer* byval align 8 %outer) #0 {
entry:
%i1 = alloca %struct.Inner, align 8
call void @llvm.dbg.declare(metadata %struct.Outer* %outer, metadata !25, metadata !2), !dbg !26
call void @llvm.dbg.declare(metadata %struct.Inner* %i1, metadata !27, metadata !2), !dbg !28
%inner = getelementptr inbounds %struct.Outer* %outer, i32 0, i32 0, !dbg !28
%arrayidx = getelementptr inbounds [2 x %struct.Inner]* %inner, i32 0, i64 1, !dbg !28
%0 = bitcast %struct.Inner* %i1 to i8*, !dbg !28
%1 = bitcast %struct.Inner* %arrayidx to i8*, !dbg !28
call void @llvm.memcpy.p0i8.p0i8.i64(i8* %0, i8* %1, i64 16, i32 8, i1 false), !dbg !28
%a = getelementptr inbounds %struct.Inner* %i1, i32 0, i32 0, !dbg !29
%2 = load i32* %a, align 4, !dbg !29
ret i32 %2, !dbg !29
}
; Function Attrs: nounwind readnone
declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
; Function Attrs: nounwind
declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture readonly, i64, i32, i1) #2
attributes #0 = { nounwind ssp uwtable }
attributes #1 = { nounwind readnone }
attributes #2 = { nounwind }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!22, !23}
!llvm.ident = !{!24}
!0 = !{!"0x11\0012\00clang version 3.5.0 \000\00\000\00\001", !1, !2, !2, !3, !2, !2} ; [ DW_TAG_compile_unit ] [ DW_TAG_compile_unit ] [sroasplit-1.c] [DW_LANG_C99]
!1 = !{!"sroasplit-1.c", !""}
!2 = !{}
!3 = !{!4}
!4 = !{!"0x2e\00foo\00foo\00\0010\000\001\000\006\00256\000\0010", !1, !5, !6, null, i32 (%struct.Outer*)* @foo, null, null, !2} ; [ DW_TAG_subprogram ] [ DW_TAG_subprogram ] [line 10] [def] [foo]
!5 = !{!"0x29", !1} ; [ DW_TAG_file_type ] [ DW_TAG_file_type ] [sroasplit-1.c]
!6 = !{!"0x15\00\000\000\000\000\000\000", i32 0, null, null, !7, null, null, null} ; [ DW_TAG_subroutine_type ] [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!7 = !{!8, !9}
!8 = !{!"0x24\00int\000\0032\0032\000\000\005", null, null} ; [ DW_TAG_base_type ] [ DW_TAG_base_type ] [int] [line 0, size 32, align 32, offset 0, enc DW_ATE_signed]
!9 = !{!"0x16\00Outer\008\000\000\000\000", !1, null, !10} ; [ DW_TAG_typedef ] [ DW_TAG_typedef ] [Outer] [line 8, size 0, align 0, offset 0] [from ]
!10 = !{!"0x13\00\006\00256\0064\000\000\000", !1, null, null, !11, null, null, null} ; [ DW_TAG_structure_type ] [line 6, size 256, align 64, offset 0] [def] [from ]
!11 = !{!12}
!12 = !{!"0xd\00inner\007\00256\0064\000\000", !1, !10, !13} ; [ DW_TAG_member ] [inner] [line 7, size 256, align 64, offset 0] [from ]
!13 = !{!"0x1\00\000\00256\0064\000\000", null, null, !14, !20, i32 0, null, null, null} ; [ DW_TAG_array_type ] [line 0, size 256, align 64, offset 0] [from Inner]
!14 = !{!"0x16\00Inner\004\000\000\000\000", !1, null, !15} ; [ DW_TAG_typedef ] [ DW_TAG_typedef ] [Inner] [line 4, size 0, align 0, offset 0] [from ]
!15 = !{!"0x13\00\001\00128\0064\000\000\000", !1, null, null, !16, null, null, null} ; [ DW_TAG_structure_type ] [line 1, size 128, align 64, offset 0] [def] [from ]
!16 = !{!17, !18}
!17 = !{!"0xd\00a\002\0032\0032\000\000", !1, !15, !8} ; [ DW_TAG_member ] [a] [line 2, size 32, align 32, offset 0] [from int]
!18 = !{!"0xd\00b\003\0064\0064\0064\000", !1, !15, !19} ; [ DW_TAG_member ] [b] [line 3, size 64, align 64, offset 64] [from long int]
!19 = !{!"0x24\00long int\000\0064\0064\000\000\005", null, null} ; [ DW_TAG_base_type ] [ DW_TAG_base_type ] [long int] [line 0, size 64, align 64, offset 0, enc DW_ATE_signed]
!20 = !{!21}
!21 = !{!"0x21\000\002"} ; [ DW_TAG_subrange_type ] [0, 1]
!22 = !{i32 2, !"Dwarf Version", i32 2}
!23 = !{i32 1, !"Debug Info Version", i32 2}
!24 = !{!"clang version 3.5.0 "}
!25 = !{!"0x101\00outer\0016777226\000", !4, !5, !9} ; [ DW_TAG_arg_variable ] [ DW_TAG_arg_variable ] [outer] [line 10]
!26 = !MDLocation(line: 10, scope: !4)
!27 = !{!"0x100\00i1\0011\000", !4, !5, !14} ; [ DW_TAG_auto_variable ] [ DW_TAG_auto_variable ] [i1] [line 11]
!28 = !MDLocation(line: 11, scope: !4)
!29 = !MDLocation(line: 12, scope: !4)

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@ -0,0 +1,102 @@
; RUN: opt %s -sroa -verify -S -o - | FileCheck %s
;
; Test that we can partial emit debug info for aggregates repeatedly
; split up by SROA.
;
; // Compile with -O1
; typedef struct {
; int a;
; int b;
; } Inner;
;
; typedef struct {
; Inner inner[2];
; } Outer;
;
; int foo(Outer outer) {
; Inner i1 = outer.inner[1];
; return i1.a;
; }
;
; Verify that SROA creates a variable piece when splitting i1.
; CHECK: call void @llvm.dbg.value(metadata i64 %outer.coerce0, i64 0, metadata ![[O:[0-9]+]], metadata ![[PIECE1:[0-9]+]]),
; CHECK: call void @llvm.dbg.value(metadata i64 %outer.coerce1, i64 0, metadata ![[O]], metadata ![[PIECE2:[0-9]+]]),
; CHECK: call void @llvm.dbg.value({{.*}}, i64 0, metadata ![[I1:[0-9]+]], metadata ![[PIECE3:[0-9]+]]),
; CHECK-DAG: ![[O]] = {{.*}} [ DW_TAG_arg_variable ] [outer] [line 10]
; CHECK-DAG: ![[PIECE1]] = {{.*}} [ DW_TAG_expression ] [DW_OP_piece offset=0, size=8]
; CHECK-DAG: ![[PIECE2]] = {{.*}} [ DW_TAG_expression ] [DW_OP_piece offset=8, size=8]
; CHECK-DAG: ![[I1]] = {{.*}} [ DW_TAG_auto_variable ] [i1] [line 11]
; CHECK-DAG: ![[PIECE3]] = {{.*}} [ DW_TAG_expression ] [DW_OP_piece offset=0, size=4]
; ModuleID = 'sroasplit-2.c'
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.9.0"
%struct.Outer = type { [2 x %struct.Inner] }
%struct.Inner = type { i32, i32 }
; Function Attrs: nounwind ssp uwtable
define i32 @foo(i64 %outer.coerce0, i64 %outer.coerce1) #0 {
%outer = alloca %struct.Outer, align 8
%i1 = alloca %struct.Inner, align 4
%1 = bitcast %struct.Outer* %outer to { i64, i64 }*
%2 = getelementptr { i64, i64 }* %1, i32 0, i32 0
store i64 %outer.coerce0, i64* %2
%3 = getelementptr { i64, i64 }* %1, i32 0, i32 1
store i64 %outer.coerce1, i64* %3
call void @llvm.dbg.declare(metadata %struct.Outer* %outer, metadata !24, metadata !2), !dbg !25
call void @llvm.dbg.declare(metadata %struct.Inner* %i1, metadata !26, metadata !2), !dbg !27
%4 = getelementptr inbounds %struct.Outer* %outer, i32 0, i32 0, !dbg !27
%5 = getelementptr inbounds [2 x %struct.Inner]* %4, i32 0, i64 1, !dbg !27
%6 = bitcast %struct.Inner* %i1 to i8*, !dbg !27
%7 = bitcast %struct.Inner* %5 to i8*, !dbg !27
call void @llvm.memcpy.p0i8.p0i8.i64(i8* %6, i8* %7, i64 8, i32 4, i1 false), !dbg !27
%8 = getelementptr inbounds %struct.Inner* %i1, i32 0, i32 0, !dbg !28
%9 = load i32* %8, align 4, !dbg !28
ret i32 %9, !dbg !28
}
; Function Attrs: nounwind readnone
declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
; Function Attrs: nounwind
declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture readonly, i64, i32, i1) #2
attributes #0 = { nounwind ssp uwtable "no-frame-pointer-elim"="true" }
attributes #1 = { nounwind readnone }
attributes #2 = { nounwind }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!21, !22}
!llvm.ident = !{!23}
!0 = !{!"0x11\0012\00clang version 3.5.0 \000\00\000\00\001", !1, !2, !2, !3, !2, !2} ; [ DW_TAG_compile_unit ] [ DW_TAG_compile_unit ] [sroasplit-2.c] [DW_LANG_C99]
!1 = !{!"sroasplit-2.c", !""}
!2 = !{}
!3 = !{!4}
!4 = !{!"0x2e\00foo\00foo\00\0010\000\001\000\006\00256\000\0010", !1, !5, !6, null, i32 (i64, i64)* @foo, null, null, !2} ; [ DW_TAG_subprogram ] [ DW_TAG_subprogram ] [line 10] [def] [foo]
!5 = !{!"0x29", !1} ; [ DW_TAG_file_type ] [ DW_TAG_file_type ] [sroasplit-2.c]
!6 = !{!"0x15\00\000\000\000\000\000\000", i32 0, null, null, !7, null, null, null} ; [ DW_TAG_subroutine_type ] [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!7 = !{!8, !9}
!8 = !{!"0x24\00int\000\0032\0032\000\000\005", null, null} ; [ DW_TAG_base_type ] [ DW_TAG_base_type ] [int] [line 0, size 32, align 32, offset 0, enc DW_ATE_signed]
!9 = !{!"0x16\00Outer\008\000\000\000\000", !1, null, !10} ; [ DW_TAG_typedef ] [ DW_TAG_typedef ] [Outer] [line 8, size 0, align 0, offset 0] [from ]
!10 = !{!"0x13\00\006\00128\0032\000\000\000", !1, null, null, !11, null, null, null} ; [ DW_TAG_structure_type ] [line 6, size 128, align 32, offset 0] [def] [from ]
!11 = !{!12}
!12 = !{!"0xd\00inner\007\00128\0032\000\000", !1, !10, !13} ; [ DW_TAG_member ] [inner] [line 7, size 128, align 32, offset 0] [from ]
!13 = !{!"0x1\00\000\00128\0032\000\000", null, null, !14, !19, i32 0, null, null, null} ; [ DW_TAG_array_type ] [line 0, size 128, align 32, offset 0] [from Inner]
!14 = !{!"0x16\00Inner\004\000\000\000\000", !1, null, !15} ; [ DW_TAG_typedef ] [ DW_TAG_typedef ] [Inner] [line 4, size 0, align 0, offset 0] [from ]
!15 = !{!"0x13\00\001\0064\0032\000\000\000", !1, null, null, !16, null, null, null} ; [ DW_TAG_structure_type ] [line 1, size 64, align 32, offset 0] [def] [from ]
!16 = !{!17, !18}
!17 = !{!"0xd\00a\002\0032\0032\000\000", !1, !15, !8} ; [ DW_TAG_member ] [a] [line 2, size 32, align 32, offset 0] [from int]
!18 = !{!"0xd\00b\003\0032\0032\0032\000", !1, !15, !8} ; [ DW_TAG_member ] [b] [line 3, size 32, align 32, offset 32] [from int]
!19 = !{!20}
!20 = !{!"0x21\000\002"} ; [ DW_TAG_subrange_type ] [0, 1]
!21 = !{i32 2, !"Dwarf Version", i32 2}
!22 = !{i32 1, !"Debug Info Version", i32 2}
!23 = !{!"clang version 3.5.0 "}
!24 = !{!"0x101\00outer\0016777226\000", !4, !5, !9} ; [ DW_TAG_arg_variable ] [ DW_TAG_arg_variable ] [outer] [line 10]
!25 = !MDLocation(line: 10, scope: !4)
!26 = !{!"0x100\00i1\0011\000", !4, !5, !14} ; [ DW_TAG_auto_variable ] [ DW_TAG_auto_variable ] [i1] [line 11]
!27 = !MDLocation(line: 11, scope: !4)
!28 = !MDLocation(line: 12, scope: !4)

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@ -0,0 +1,63 @@
; RUN: opt %s -sroa -verify -S -o - | FileCheck %s
; ModuleID = 'test.c'
; Test that SROA updates the debug info correctly if an alloca was rewritten but
; not partitioned into multiple allocas.
;
; CHECK: call void @llvm.dbg.value(metadata float %s.coerce, i64 0, metadata ![[VAR:[0-9]+]], metadata ![[EXPR:[0-9]+]])
; CHECK: ![[VAR]] = {{.*}} [ DW_TAG_arg_variable ] [s] [line 3]
; CHECK: ![[EXPR]] = {{.*}} [ DW_TAG_expression ]
; CHECK-NOT: DW_OP_piece
;
; struct S { float f; };
;
; float foo(struct S s) {
; return s.f;
; }
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.10.0"
%struct.S = type { float }
; Function Attrs: nounwind ssp uwtable
define float @foo(float %s.coerce) #0 {
entry:
%s = alloca %struct.S, align 4
%coerce.dive = getelementptr %struct.S* %s, i32 0, i32 0
store float %s.coerce, float* %coerce.dive, align 1
call void @llvm.dbg.declare(metadata %struct.S* %s, metadata !16, metadata !17), !dbg !18
%f = getelementptr inbounds %struct.S* %s, i32 0, i32 0, !dbg !19
%0 = load float* %f, align 4, !dbg !19
ret float %0, !dbg !19
}
; Function Attrs: nounwind readnone
declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
attributes #0 = { nounwind ssp uwtable }
attributes #1 = { nounwind readnone }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!12, !13, !14}
!llvm.ident = !{!15}
!0 = !{!"0x11\0012\00clang version 3.6.0 \000\00\000\00\001", !1, !2, !2, !3, !2, !2} ; [ DW_TAG_compile_unit ] [/Volumes/Data/llvm/_build.ninja.debug/test.c] [DW_LANG_C99]
!1 = !{!"test.c", !"/Volumes/Data/llvm/_build.ninja.debug"}
!2 = !{}
!3 = !{!4}
!4 = !{!"0x2e\00foo\00foo\00\003\000\001\000\000\00256\000\003", !1, !5, !6, null, float (float)* @foo, null, null, !2} ; [ DW_TAG_subprogram ] [line 3] [def] [foo]
!5 = !{!"0x29", !1} ; [ DW_TAG_file_type ] [/Volumes/Data/llvm/_build.ninja.debug/test.c]
!6 = !{!"0x15\00\000\000\000\000\000\000", null, null, null, !7, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!7 = !{!8, !9}
!8 = !{!"0x24\00float\000\0032\0032\000\000\004", null, null} ; [ DW_TAG_base_type ] [float] [line 0, size 32, align 32, offset 0, enc DW_ATE_float]
!9 = !{!"0x13\00S\001\0032\0032\000\000\000", !1, null, null, !10, null, null, null} ; [ DW_TAG_structure_type ] [S] [line 1, size 32, align 32, offset 0] [def] [from ]
!10 = !{!11}
!11 = !{!"0xd\00f\001\0032\0032\000\000", !1, !9, !8} ; [ DW_TAG_member ] [f] [line 1, size 32, align 32, offset 0] [from float]
!12 = !{i32 2, !"Dwarf Version", i32 2}
!13 = !{i32 2, !"Debug Info Version", i32 2}
!14 = !{i32 1, !"PIC Level", i32 2}
!15 = !{!"clang version 3.6.0 "}
!16 = !{!"0x101\00s\0016777219\000", !4, !5, !9} ; [ DW_TAG_arg_variable ] [s] [line 3]
!17 = !{!"0x102"} ; [ DW_TAG_expression ]
!18 = !MDLocation(line: 3, column: 20, scope: !4)
!19 = !MDLocation(line: 4, column: 2, scope: !4)