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llvm-project/llvm/test/CodeGen/X86/push-cfi-debug.ll

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[X86] Generate .cfi_adjust_cfa_offset correctly when pushing arguments When push instructions are being used to pass function arguments on the stack, and either EH or debugging are enabled, we need to generate .cfi_adjust_cfa_offset directives appropriately. For (synch) EH, it is enough for the CFA offset to be correct at every call site, while for debugging we want to be correct after every push. Darwin does not support this well, so don't use pushes whenever it would be required. Differential Revision: http://reviews.llvm.org/D13767 llvm-svn: 251904
2015-11-03 16:17:25 +08:00
; RUN: llc < %s -mtriple=i686-pc-linux | FileCheck %s
; Function Attrs: optsize
declare void @foo(i32, i32) #0
declare x86_stdcallcc void @stdfoo(i32, i32) #0
; CHECK-LABEL: test1:
Correct dwarf unwind information in function epilogue This patch aims to provide correct dwarf unwind information in function epilogue for X86. It consists of two parts. The first part inserts CFI instructions that set appropriate cfa offset and cfa register in emitEpilogue() in X86FrameLowering. This part is X86 specific. The second part is platform independent and ensures that: * CFI instructions do not affect code generation (they are not counted as instructions when tail duplicating or tail merging) * Unwind information remains correct when a function is modified by different passes. This is done in a late pass by analyzing information about cfa offset and cfa register in BBs and inserting additional CFI directives where necessary. Added CFIInstrInserter pass: * analyzes each basic block to determine cfa offset and register are valid at its entry and exit * verifies that outgoing cfa offset and register of predecessor blocks match incoming values of their successors * inserts additional CFI directives at basic block beginning to correct the rule for calculating CFA Having CFI instructions in function epilogue can cause incorrect CFA calculation rule for some basic blocks. This can happen if, due to basic block reordering, or the existence of multiple epilogue blocks, some of the blocks have wrong cfa offset and register values set by the epilogue block above them. CFIInstrInserter is currently run only on X86, but can be used by any target that implements support for adding CFI instructions in epilogue. Patch by Violeta Vukobrat. Differential Revision: https://reviews.llvm.org/D42848 llvm-svn: 330706
2018-04-24 18:32:08 +08:00
; CHECK: subl $20, %esp
; CHECK: .cfi_adjust_cfa_offset 20
[X86] Generate .cfi_adjust_cfa_offset correctly when pushing arguments When push instructions are being used to pass function arguments on the stack, and either EH or debugging are enabled, we need to generate .cfi_adjust_cfa_offset directives appropriately. For (synch) EH, it is enough for the CFA offset to be correct at every call site, while for debugging we want to be correct after every push. Darwin does not support this well, so don't use pushes whenever it would be required. Differential Revision: http://reviews.llvm.org/D13767 llvm-svn: 251904
2015-11-03 16:17:25 +08:00
; CHECK: pushl $2
; CHECK: .cfi_adjust_cfa_offset 4
; CHECK: pushl $1
; CHECK: .cfi_adjust_cfa_offset 4
; CHECK: calll foo
Correct dwarf unwind information in function epilogue This patch aims to provide correct dwarf unwind information in function epilogue for X86. It consists of two parts. The first part inserts CFI instructions that set appropriate cfa offset and cfa register in emitEpilogue() in X86FrameLowering. This part is X86 specific. The second part is platform independent and ensures that: * CFI instructions do not affect code generation (they are not counted as instructions when tail duplicating or tail merging) * Unwind information remains correct when a function is modified by different passes. This is done in a late pass by analyzing information about cfa offset and cfa register in BBs and inserting additional CFI directives where necessary. Added CFIInstrInserter pass: * analyzes each basic block to determine cfa offset and register are valid at its entry and exit * verifies that outgoing cfa offset and register of predecessor blocks match incoming values of their successors * inserts additional CFI directives at basic block beginning to correct the rule for calculating CFA Having CFI instructions in function epilogue can cause incorrect CFA calculation rule for some basic blocks. This can happen if, due to basic block reordering, or the existence of multiple epilogue blocks, some of the blocks have wrong cfa offset and register values set by the epilogue block above them. CFIInstrInserter is currently run only on X86, but can be used by any target that implements support for adding CFI instructions in epilogue. Patch by Violeta Vukobrat. Differential Revision: https://reviews.llvm.org/D42848 llvm-svn: 330706
2018-04-24 18:32:08 +08:00
; CHECK: addl $8, %esp
; CHECK: .cfi_adjust_cfa_offset -8
[X86] Generate .cfi_adjust_cfa_offset correctly when pushing arguments When push instructions are being used to pass function arguments on the stack, and either EH or debugging are enabled, we need to generate .cfi_adjust_cfa_offset directives appropriately. For (synch) EH, it is enough for the CFA offset to be correct at every call site, while for debugging we want to be correct after every push. Darwin does not support this well, so don't use pushes whenever it would be required. Differential Revision: http://reviews.llvm.org/D13767 llvm-svn: 251904
2015-11-03 16:17:25 +08:00
; CHECK: pushl $4
; CHECK: .cfi_adjust_cfa_offset 4
; CHECK: pushl $3
; CHECK: .cfi_adjust_cfa_offset 4
; CHECK: calll stdfoo
; CHECK: .cfi_adjust_cfa_offset -8
Revert "Correct dwarf unwind information in function epilogue for X86" This reverts r317579, originally committed as r317100. There is a design issue with marking CFI instructions duplicatable. Not all targets support the CFIInstrInserter pass, and targets like Darwin can't cope with duplicated prologue setup CFI instructions. The compact unwind info emission fails. When the following code is compiled for arm64 on Mac at -O3, the CFI instructions end up getting tail duplicated, which causes compact unwind info emission to fail: int a, c, d, e, f, g, h, i, j, k, l, m; void n(int o, int *b) { if (g) f = 0; for (; f < o; f++) { m = a; if (l > j * k > i) j = i = k = d; h = b[c] - e; } } We get assembly that looks like this: ; BB#1: ; %if.then Lloh3: adrp x9, _f@GOTPAGE Lloh4: ldr x9, [x9, _f@GOTPAGEOFF] mov w8, wzr Lloh5: str wzr, [x9] stp x20, x19, [sp, #-16]! ; 8-byte Folded Spill .cfi_def_cfa_offset 16 .cfi_offset w19, -8 .cfi_offset w20, -16 cmp w8, w0 b.lt LBB0_3 b LBB0_7 LBB0_2: ; %entry.if.end_crit_edge Lloh6: adrp x8, _f@GOTPAGE Lloh7: ldr x8, [x8, _f@GOTPAGEOFF] Lloh8: ldr w8, [x8] stp x20, x19, [sp, #-16]! ; 8-byte Folded Spill .cfi_def_cfa_offset 16 .cfi_offset w19, -8 .cfi_offset w20, -16 cmp w8, w0 b.ge LBB0_7 LBB0_3: ; %for.body.lr.ph Note the multiple .cfi_def* directives. Compact unwind info emission can't handle that. llvm-svn: 317726
2017-11-09 05:31:14 +08:00
; CHECK: addl $20, %esp
Correct dwarf unwind information in function epilogue This patch aims to provide correct dwarf unwind information in function epilogue for X86. It consists of two parts. The first part inserts CFI instructions that set appropriate cfa offset and cfa register in emitEpilogue() in X86FrameLowering. This part is X86 specific. The second part is platform independent and ensures that: * CFI instructions do not affect code generation (they are not counted as instructions when tail duplicating or tail merging) * Unwind information remains correct when a function is modified by different passes. This is done in a late pass by analyzing information about cfa offset and cfa register in BBs and inserting additional CFI directives where necessary. Added CFIInstrInserter pass: * analyzes each basic block to determine cfa offset and register are valid at its entry and exit * verifies that outgoing cfa offset and register of predecessor blocks match incoming values of their successors * inserts additional CFI directives at basic block beginning to correct the rule for calculating CFA Having CFI instructions in function epilogue can cause incorrect CFA calculation rule for some basic blocks. This can happen if, due to basic block reordering, or the existence of multiple epilogue blocks, some of the blocks have wrong cfa offset and register values set by the epilogue block above them. CFIInstrInserter is currently run only on X86, but can be used by any target that implements support for adding CFI instructions in epilogue. Patch by Violeta Vukobrat. Differential Revision: https://reviews.llvm.org/D42848 llvm-svn: 330706
2018-04-24 18:32:08 +08:00
; CHECK: .cfi_adjust_cfa_offset -20
DI: Reverse direction of subprogram -> function edge. Previously, subprograms contained a metadata reference to the function they described. Because most clients need to get or set a subprogram for a given function rather than the other way around, this created unneeded inefficiency. For example, many passes needed to call the function llvm::makeSubprogramMap() to build a mapping from functions to subprograms, and the IR linker needed to fix up function references in a way that caused quadratic complexity in the IR linking phase of LTO. This change reverses the direction of the edge by storing the subprogram as function-level metadata and removing DISubprogram's function field. Since this is an IR change, a bitcode upgrade has been provided. Fixes PR23367. An upgrade script for textual IR for out-of-tree clients is attached to the PR. Differential Revision: http://reviews.llvm.org/D14265 llvm-svn: 252219
2015-11-06 06:03:56 +08:00
define void @test1() #0 !dbg !4 {
[X86] Generate .cfi_adjust_cfa_offset correctly when pushing arguments When push instructions are being used to pass function arguments on the stack, and either EH or debugging are enabled, we need to generate .cfi_adjust_cfa_offset directives appropriately. For (synch) EH, it is enough for the CFA offset to be correct at every call site, while for debugging we want to be correct after every push. Darwin does not support this well, so don't use pushes whenever it would be required. Differential Revision: http://reviews.llvm.org/D13767 llvm-svn: 251904
2015-11-03 16:17:25 +08:00
entry:
tail call void @foo(i32 1, i32 2) #1, !dbg !10
tail call x86_stdcallcc void @stdfoo(i32 3, i32 4) #1, !dbg !11
ret void, !dbg !12
}
attributes #0 = { nounwind optsize }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!7, !8}
!llvm.ident = !{!9}
[PR27284] Reverse the ownership between DICompileUnit and DISubprogram. Currently each Function points to a DISubprogram and DISubprogram has a scope field. For member functions the scope is a DICompositeType. DIScopes point to the DICompileUnit to facilitate type uniquing. Distinct DISubprograms (with isDefinition: true) are not part of the type hierarchy and cannot be uniqued. This change removes the subprograms list from DICompileUnit and instead adds a pointer to the owning compile unit to distinct DISubprograms. This would make it easy for ThinLTO to strip unneeded DISubprograms and their transitively referenced debug info. Motivation ---------- Materializing DISubprograms is currently the most expensive operation when doing a ThinLTO build of clang. We want the DISubprogram to be stored in a separate Bitcode block (or the same block as the function body) so we can avoid having to expensively deserialize all DISubprograms together with the global metadata. If a function has been inlined into another subprogram we need to store a reference the block containing the inlined subprogram. Attached to https://llvm.org/bugs/show_bug.cgi?id=27284 is a python script that updates LLVM IR testcases to the new format. http://reviews.llvm.org/D19034 <rdar://problem/25256815> llvm-svn: 266446
2016-04-15 23:57:41 +08:00
!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 3.8.0 (trunk 250289)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
[X86] Generate .cfi_adjust_cfa_offset correctly when pushing arguments When push instructions are being used to pass function arguments on the stack, and either EH or debugging are enabled, we need to generate .cfi_adjust_cfa_offset directives appropriately. For (synch) EH, it is enough for the CFA offset to be correct at every call site, while for debugging we want to be correct after every push. Darwin does not support this well, so don't use pushes whenever it would be required. Differential Revision: http://reviews.llvm.org/D13767 llvm-svn: 251904
2015-11-03 16:17:25 +08:00
!1 = !DIFile(filename: "foo.c", directory: "foo")
!2 = !{}
[PR27284] Reverse the ownership between DICompileUnit and DISubprogram. Currently each Function points to a DISubprogram and DISubprogram has a scope field. For member functions the scope is a DICompositeType. DIScopes point to the DICompileUnit to facilitate type uniquing. Distinct DISubprograms (with isDefinition: true) are not part of the type hierarchy and cannot be uniqued. This change removes the subprograms list from DICompileUnit and instead adds a pointer to the owning compile unit to distinct DISubprograms. This would make it easy for ThinLTO to strip unneeded DISubprograms and their transitively referenced debug info. Motivation ---------- Materializing DISubprograms is currently the most expensive operation when doing a ThinLTO build of clang. We want the DISubprogram to be stored in a separate Bitcode block (or the same block as the function body) so we can avoid having to expensively deserialize all DISubprograms together with the global metadata. If a function has been inlined into another subprogram we need to store a reference the block containing the inlined subprogram. Attached to https://llvm.org/bugs/show_bug.cgi?id=27284 is a python script that updates LLVM IR testcases to the new format. http://reviews.llvm.org/D19034 <rdar://problem/25256815> llvm-svn: 266446
2016-04-15 23:57:41 +08:00
!4 = distinct !DISubprogram(name: "test1", scope: !1, file: !1, line: 3, type: !5, isLocal: false, isDefinition: true, scopeLine: 3, isOptimized: true, unit: !0, variables: !2)
[X86] Generate .cfi_adjust_cfa_offset correctly when pushing arguments When push instructions are being used to pass function arguments on the stack, and either EH or debugging are enabled, we need to generate .cfi_adjust_cfa_offset directives appropriately. For (synch) EH, it is enough for the CFA offset to be correct at every call site, while for debugging we want to be correct after every push. Darwin does not support this well, so don't use pushes whenever it would be required. Differential Revision: http://reviews.llvm.org/D13767 llvm-svn: 251904
2015-11-03 16:17:25 +08:00
!5 = !DISubroutineType(types: !6)
!6 = !{null}
!7 = !{i32 2, !"Dwarf Version", i32 4}
!8 = !{i32 2, !"Debug Info Version", i32 3}
!9 = !{!"clang version 3.8.0 (trunk 250289)"}
!10 = !DILocation(line: 4, column: 3, scope: !4)
!11 = !DILocation(line: 5, column: 3, scope: !4)
!12 = !DILocation(line: 6, column: 1, scope: !4)