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llvm-project/llvm/test/DebugInfo/dead-argument-order.ll

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PR19388: DebugInfo: Emit dead arguments in their originally declared order. Unused arguments were not being added to the argument list, but instead treated as arbitrary scope variables. This meant they weren't carefully added in the original argument order. In this particular example, though, it turns out the argument is only /mostly/ unused (well, actually it's entirely used, but in a specific way). It's a struct that, due to ABI reasons, is decomposed into chunks (exactly one chunk, since it has one member) and then passed. Since only one of those chunks is used (SROA, etc, kill the original reconstitution code) we don't have a location to describe the whole variable. In this particular case, since the struct consists of just the one int, once we have partial location information, this should have a location that describes the entire variable (since the piece is the entirety of the object). And at some point we'll need to describe the location of even /entirely/ unused arguments so that they can at least be printed on function entry. llvm-svn: 210231
2014-06-05 08:51:35 +08:00
; REQUIRES: object-emission
; RUN: %llc_dwarf -O0 -filetype=obj < %s | llvm-dwarfdump -debug-dump=info - | FileCheck %s
; Built from the following source with clang -O1
; struct S { int i; };
; int function(struct S s, int i) { return s.i + i; }
; Due to the X86_64 ABI, 's' is passed in registers and once optimized, the
; entirety of 's' is never reconstituted, since only the int is required, and
; thus the variable's location is unknown/dead to debug info.
; Future/current work should enable us to describe partial variables, which, in
; this case, happens to be the entire variable.
; CHECK: DW_TAG_subprogram
; CHECK-NOT: DW_TAG
; CHECK: DW_AT_name {{.*}} "function"
; CHECK-NOT: {{DW_TAG|NULL}}
; CHECK: DW_TAG_formal_parameter
; CHECK-NOT: DW_TAG
; CHECK: DW_AT_name {{.*}} "s"
; CHECK-NOT: DW_TAG
; FIXME: Even though 's' is never reconstituted into a struct, the one member
; variable is still live and used, and so we should be able to describe 's's
; location as the location of that int.
; CHECK-NOT: DW_AT_location
; CHECK-NOT: {{DW_TAG|NULL}}
; CHECK: DW_TAG_formal_parameter
; CHECK-NOT: DW_TAG
; CHECK: DW_AT_location
DebugInfo: Following up to r209677, refactor local variable emission to delay the choice between emitting the definition attributes or using DW_AT_abstract_definition This doesn't fix the abstract variable handling yet, but it introduces a similar delay mechanism as was added for subprograms, causing DW_AT_location to be reordered to the beginning of the attribute list for local variables, and fixes all the test fallout for that. A subsequent commit will remove the abstract variable handling in DbgVariable and just do the abstract variable lookup at module end to ensure that abstract variables introduced after their concrete counterparts are appropriately referenced by the concrete variable. llvm-svn: 210943
2014-06-14 06:18:23 +08:00
; CHECK-NOT: DW_TAG
; CHECK: DW_AT_name {{.*}} "i"
PR19388: DebugInfo: Emit dead arguments in their originally declared order. Unused arguments were not being added to the argument list, but instead treated as arbitrary scope variables. This meant they weren't carefully added in the original argument order. In this particular example, though, it turns out the argument is only /mostly/ unused (well, actually it's entirely used, but in a specific way). It's a struct that, due to ABI reasons, is decomposed into chunks (exactly one chunk, since it has one member) and then passed. Since only one of those chunks is used (SROA, etc, kill the original reconstitution code) we don't have a location to describe the whole variable. In this particular case, since the struct consists of just the one int, once we have partial location information, this should have a location that describes the entire variable (since the piece is the entirety of the object). And at some point we'll need to describe the location of even /entirely/ unused arguments so that they can at least be printed on function entry. llvm-svn: 210231
2014-06-05 08:51:35 +08:00
%struct.S = type { i32 }
; Function Attrs: nounwind readnone uwtable
define i32 @_Z8function1Si(i32 %s.coerce, i32 %i) #0 {
entry:
IR: Make metadata typeless in assembly Now that `Metadata` is typeless, reflect that in the assembly. These are the matching assembly changes for the metadata/value split in r223802. - Only use the `metadata` type when referencing metadata from a call intrinsic -- i.e., only when it's used as a `Value`. - Stop pretending that `ValueAsMetadata` is wrapped in an `MDNode` when referencing it from call intrinsics. So, assembly like this: define @foo(i32 %v) { call void @llvm.foo(metadata !{i32 %v}, metadata !0) call void @llvm.foo(metadata !{i32 7}, metadata !0) call void @llvm.foo(metadata !1, metadata !0) call void @llvm.foo(metadata !3, metadata !0) call void @llvm.foo(metadata !{metadata !3}, metadata !0) ret void, !bar !2 } !0 = metadata !{metadata !2} !1 = metadata !{i32* @global} !2 = metadata !{metadata !3} !3 = metadata !{} turns into this: define @foo(i32 %v) { call void @llvm.foo(metadata i32 %v, metadata !0) call void @llvm.foo(metadata i32 7, metadata !0) call void @llvm.foo(metadata i32* @global, metadata !0) call void @llvm.foo(metadata !3, metadata !0) call void @llvm.foo(metadata !{!3}, metadata !0) ret void, !bar !2 } !0 = !{!2} !1 = !{i32* @global} !2 = !{!3} !3 = !{} I wrote an upgrade script that handled almost all of the tests in llvm and many of the tests in cfe (even handling many `CHECK` lines). I've attached it (or will attach it in a moment if you're speedy) to PR21532 to help everyone update their out-of-tree testcases. This is part of PR21532. llvm-svn: 224257
2014-12-16 03:07:53 +08:00
tail call void @llvm.dbg.declare(metadata %struct.S* undef, metadata !14, metadata !{!"0x102"}), !dbg !20
tail call void @llvm.dbg.value(metadata i32 %i, i64 0, metadata !15, metadata !{!"0x102"}), !dbg !20
PR19388: DebugInfo: Emit dead arguments in their originally declared order. Unused arguments were not being added to the argument list, but instead treated as arbitrary scope variables. This meant they weren't carefully added in the original argument order. In this particular example, though, it turns out the argument is only /mostly/ unused (well, actually it's entirely used, but in a specific way). It's a struct that, due to ABI reasons, is decomposed into chunks (exactly one chunk, since it has one member) and then passed. Since only one of those chunks is used (SROA, etc, kill the original reconstitution code) we don't have a location to describe the whole variable. In this particular case, since the struct consists of just the one int, once we have partial location information, this should have a location that describes the entire variable (since the piece is the entirety of the object). And at some point we'll need to describe the location of even /entirely/ unused arguments so that they can at least be printed on function entry. llvm-svn: 210231
2014-06-05 08:51:35 +08:00
%add = add nsw i32 %i, %s.coerce, !dbg !20
ret i32 %add, !dbg !20
}
; Function Attrs: nounwind readnone
Move the complex address expression out of DIVariable and into an extra argument of the llvm.dbg.declare/llvm.dbg.value intrinsics. Previously, DIVariable was a variable-length field that has an optional reference to a Metadata array consisting of a variable number of complex address expressions. In the case of OpPiece expressions this is wasting a lot of storage in IR, because when an aggregate type is, e.g., SROA'd into all of its n individual members, the IR will contain n copies of the DIVariable, all alike, only differing in the complex address reference at the end. By making the complex address into an extra argument of the dbg.value/dbg.declare intrinsics, all of the pieces can reference the same variable and the complex address expressions can be uniqued across the CU, too. Down the road, this will allow us to move other flags, such as "indirection" out of the DIVariable, too. The new intrinsics look like this: declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr) declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr) This patch adds a new LLVM-local tag to DIExpressions, so we can detect and pretty-print DIExpression metadata nodes. What this patch doesn't do: This patch does not touch the "Indirect" field in DIVariable; but moving that into the expression would be a natural next step. http://reviews.llvm.org/D4919 rdar://problem/17994491 Thanks to dblaikie and dexonsmith for reviewing this patch! Note: I accidentally committed a bogus older version of this patch previously. llvm-svn: 218787
2014-10-02 02:55:02 +08:00
declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
PR19388: DebugInfo: Emit dead arguments in their originally declared order. Unused arguments were not being added to the argument list, but instead treated as arbitrary scope variables. This meant they weren't carefully added in the original argument order. In this particular example, though, it turns out the argument is only /mostly/ unused (well, actually it's entirely used, but in a specific way). It's a struct that, due to ABI reasons, is decomposed into chunks (exactly one chunk, since it has one member) and then passed. Since only one of those chunks is used (SROA, etc, kill the original reconstitution code) we don't have a location to describe the whole variable. In this particular case, since the struct consists of just the one int, once we have partial location information, this should have a location that describes the entire variable (since the piece is the entirety of the object). And at some point we'll need to describe the location of even /entirely/ unused arguments so that they can at least be printed on function entry. llvm-svn: 210231
2014-06-05 08:51:35 +08:00
; Function Attrs: nounwind readnone
Move the complex address expression out of DIVariable and into an extra argument of the llvm.dbg.declare/llvm.dbg.value intrinsics. Previously, DIVariable was a variable-length field that has an optional reference to a Metadata array consisting of a variable number of complex address expressions. In the case of OpPiece expressions this is wasting a lot of storage in IR, because when an aggregate type is, e.g., SROA'd into all of its n individual members, the IR will contain n copies of the DIVariable, all alike, only differing in the complex address reference at the end. By making the complex address into an extra argument of the dbg.value/dbg.declare intrinsics, all of the pieces can reference the same variable and the complex address expressions can be uniqued across the CU, too. Down the road, this will allow us to move other flags, such as "indirection" out of the DIVariable, too. The new intrinsics look like this: declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr) declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr) This patch adds a new LLVM-local tag to DIExpressions, so we can detect and pretty-print DIExpression metadata nodes. What this patch doesn't do: This patch does not touch the "Indirect" field in DIVariable; but moving that into the expression would be a natural next step. http://reviews.llvm.org/D4919 rdar://problem/17994491 Thanks to dblaikie and dexonsmith for reviewing this patch! Note: I accidentally committed a bogus older version of this patch previously. llvm-svn: 218787
2014-10-02 02:55:02 +08:00
declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #1
PR19388: DebugInfo: Emit dead arguments in their originally declared order. Unused arguments were not being added to the argument list, but instead treated as arbitrary scope variables. This meant they weren't carefully added in the original argument order. In this particular example, though, it turns out the argument is only /mostly/ unused (well, actually it's entirely used, but in a specific way). It's a struct that, due to ABI reasons, is decomposed into chunks (exactly one chunk, since it has one member) and then passed. Since only one of those chunks is used (SROA, etc, kill the original reconstitution code) we don't have a location to describe the whole variable. In this particular case, since the struct consists of just the one int, once we have partial location information, this should have a location that describes the entire variable (since the piece is the entirety of the object). And at some point we'll need to describe the location of even /entirely/ unused arguments so that they can at least be printed on function entry. llvm-svn: 210231
2014-06-05 08:51:35 +08:00
attributes #0 = { nounwind readnone uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #1 = { nounwind readnone }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!16, !17}
!llvm.ident = !{!18}
IR: Make metadata typeless in assembly Now that `Metadata` is typeless, reflect that in the assembly. These are the matching assembly changes for the metadata/value split in r223802. - Only use the `metadata` type when referencing metadata from a call intrinsic -- i.e., only when it's used as a `Value`. - Stop pretending that `ValueAsMetadata` is wrapped in an `MDNode` when referencing it from call intrinsics. So, assembly like this: define @foo(i32 %v) { call void @llvm.foo(metadata !{i32 %v}, metadata !0) call void @llvm.foo(metadata !{i32 7}, metadata !0) call void @llvm.foo(metadata !1, metadata !0) call void @llvm.foo(metadata !3, metadata !0) call void @llvm.foo(metadata !{metadata !3}, metadata !0) ret void, !bar !2 } !0 = metadata !{metadata !2} !1 = metadata !{i32* @global} !2 = metadata !{metadata !3} !3 = metadata !{} turns into this: define @foo(i32 %v) { call void @llvm.foo(metadata i32 %v, metadata !0) call void @llvm.foo(metadata i32 7, metadata !0) call void @llvm.foo(metadata i32* @global, metadata !0) call void @llvm.foo(metadata !3, metadata !0) call void @llvm.foo(metadata !{!3}, metadata !0) ret void, !bar !2 } !0 = !{!2} !1 = !{i32* @global} !2 = !{!3} !3 = !{} I wrote an upgrade script that handled almost all of the tests in llvm and many of the tests in cfe (even handling many `CHECK` lines). I've attached it (or will attach it in a moment if you're speedy) to PR21532 to help everyone update their out-of-tree testcases. This is part of PR21532. llvm-svn: 224257
2014-12-16 03:07:53 +08:00
!0 = !{!"0x11\004\00clang version 3.5.0 \001\00\000\00\001", !1, !2, !3, !8, !2, !2} ; [ DW_TAG_compile_unit ] [/tmp/dbginfo/dead-argument-order.cpp] [DW_LANG_C_plus_plus]
!1 = !{!"dead-argument-order.cpp", !"/tmp/dbginfo"}
!2 = !{}
!3 = !{!4}
!4 = !{!"0x13\00S\001\0032\0032\000\000\000", !1, null, null, !5, null, null, !"_ZTS1S"} ; [ DW_TAG_structure_type ] [S] [line 1, size 32, align 32, offset 0] [def] [from ]
!5 = !{!6}
!6 = !{!"0xd\00i\001\0032\0032\000\000", !1, !"_ZTS1S", !7} ; [ DW_TAG_member ] [i] [line 1, size 32, align 32, offset 0] [from int]
!7 = !{!"0x24\00int\000\0032\0032\000\000\005", null, null} ; [ DW_TAG_base_type ] [int] [line 0, size 32, align 32, offset 0, enc DW_ATE_signed]
!8 = !{!9}
!9 = !{!"0x2e\00function\00function\00_Z8function1Si\002\000\001\000\006\00256\001\002", !1, !10, !11, null, i32 (i32, i32)* @_Z8function1Si, null, null, !13} ; [ DW_TAG_subprogram ] [line 2] [def] [function]
!10 = !{!"0x29", !1} ; [ DW_TAG_file_type ] [/tmp/dbginfo/dead-argument-order.cpp]
!11 = !{!"0x15\00\000\000\000\000\000\000", i32 0, null, null, !12, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!12 = !{!7, !4, !7}
!13 = !{!14, !15}
!14 = !{!"0x101\00s\0016777218\000", !9, !10, !"_ZTS1S"} ; [ DW_TAG_arg_variable ] [s] [line 2]
!15 = !{!"0x101\00i\0033554434\000", !9, !10, !7} ; [ DW_TAG_arg_variable ] [i] [line 2]
!16 = !{i32 2, !"Dwarf Version", i32 4}
!17 = !{i32 2, !"Debug Info Version", i32 2}
!18 = !{!"clang version 3.5.0 "}
!19 = !{%struct.S* undef}
IR: Move MDLocation into place This commit moves `MDLocation`, finishing off PR21433. There's an accompanying clang commit for frontend testcases. I'll attach the testcase upgrade script I used to PR21433 to help out-of-tree frontends/backends. This changes the schema for `DebugLoc` and `DILocation` from: !{i32 3, i32 7, !7, !8} to: !MDLocation(line: 3, column: 7, scope: !7, inlinedAt: !8) Note that empty fields (line/column: 0 and inlinedAt: null) don't get printed by the assembly writer. llvm-svn: 226048
2015-01-15 06:27:36 +08:00
!20 = !MDLocation(line: 2, scope: !9)
PR19388: DebugInfo: Emit dead arguments in their originally declared order. Unused arguments were not being added to the argument list, but instead treated as arbitrary scope variables. This meant they weren't carefully added in the original argument order. In this particular example, though, it turns out the argument is only /mostly/ unused (well, actually it's entirely used, but in a specific way). It's a struct that, due to ABI reasons, is decomposed into chunks (exactly one chunk, since it has one member) and then passed. Since only one of those chunks is used (SROA, etc, kill the original reconstitution code) we don't have a location to describe the whole variable. In this particular case, since the struct consists of just the one int, once we have partial location information, this should have a location that describes the entire variable (since the piece is the entirety of the object). And at some point we'll need to describe the location of even /entirely/ unused arguments so that they can at least be printed on function entry. llvm-svn: 210231
2014-06-05 08:51:35 +08:00