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* Use iteration instead of recursion in CFIInserterSanjoy Das2018-05-111-15/+26
| | | | | | | | | | | | Summary: This recursive step can overflow the stack. Reviewers: djokov, petarj Subscribers: mcrosier, jlebar, bixia, llvm-commits Differential Revision: https://reviews.llvm.org/D46671 llvm-svn: 332101
* Add option -verify-cfiinstrs to run verifier in CFIInstrInserterPetar Jovanovic2018-05-071-5/+11
| | | | | | | | | Instead of enabling it for non NDEBUG builds, use -verify-cfiinstrs to run verifier in CFIInstrInserter. It defaults to false. Differential Revision: https://reviews.llvm.org/D46444 llvm-svn: 331635
* Skip unreachable blocks for CFIInstrInserter verifyPetar Jovanovic2018-05-071-3/+4
| | | | | | | Iterate only through reachable blocks. This finetunes r330706 and it resolves build issue reported by Craig Topper. llvm-svn: 331628
* Correct dwarf unwind information in function epiloguePetar Jovanovic2018-04-241-0/+308
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Revert "Correct dwarf unwind information in function epilogue for X86"Reid Kleckner2017-11-081-319/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Target/TargetInstrInfo.h -> CodeGen/TargetInstrInfo.h to match layeringDavid Blaikie2017-11-081-1/+1
| | | | | | | | This header includes CodeGen headers, and is not, itself, included by any Target headers, so move it into CodeGen to match the layering of its implementation. llvm-svn: 317647
* Reland "Correct dwarf unwind information in function epilogue for X86"Petar Jovanovic2017-11-071-0/+319
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Reland r317100 with minor fix regarding ComputeCommonTailLength function in BranchFolding.cpp. Skipping top CFI instructions block needs to executed on several more return points in ComputeCommonTailLength(). Original r317100 message: "Correct dwarf unwind information in function epilogue for X86" 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 - 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. Changed CFI instructions so that they: - are duplicable - are not counted as instructions when tail duplicating or tail merging - can be compared as equal Added CFIInstrInserter pass: - analyzes each basic block to determine cfa offset and register 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. llvm-svn: 317579
* Revert "Correct dwarf unwind information in function epilogue for X86"Petar Jovanovic2017-11-011-319/+0
| | | | | | | This reverts r317100 as it introduced sanitizer-x86_64-linux-autoconf buildbot failure (build #15606). llvm-svn: 317136
* Correct dwarf unwind information in function epilogue for X86Petar Jovanovic2017-11-011-0/+319
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 - 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. Changed CFI instructions so that they: - are duplicable - are not counted as instructions when tail duplicating or tail merging - can be compared as equal Added CFIInstrInserter pass: - analyzes each basic block to determine cfa offset and register 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/D35844 llvm-svn: 317100
* Revert "r306529 - [X86] Correct dwarf unwind information in function epilogue"Daniel Jasper2017-06-291-124/+0
| | | | | | | | | | I am 99% sure that this breaks the PPC ASAN build bot: http://lab.llvm.org:8011/builders/sanitizer-ppc64be-linux/builds/3112/steps/64-bit%20check-asan/logs/stdio If it doesn't go back to green, we can recommit (and fix the original commit message at the same time :) ). llvm-svn: 306676
* [X86] Correct dwarf unwind information in function epiloguePetar Jovanovic2017-06-281-0/+124
CFI instructions that set appropriate cfa offset and cfa register are now inserted in emitEpilogue() in X86FrameLowering. Majority of the changes in this patch: 1. Ensure that CFI instructions do not affect code generation. 2. Enable maintaining correct information about cfa offset and cfa register in a function when basic blocks are reordered, merged, split, duplicated. These changes are target independent and described below. Changed CFI instructions so that they: 1. are duplicable 2. are not counted as instructions when tail duplicating or tail merging 3. can be compared as equal Add information to each MachineBasicBlock about cfa offset and cfa register that are valid at its entry and exit (incoming and outgoing CFI info). Add support for updating this information when basic blocks are merged, split, duplicated, created. Add a verification pass (CFIInfoVerifier) that checks that outgoing cfa offset and register of predecessor blocks match incoming values of their successors. Incoming and outgoing CFI information is used by a late pass (CFIInstrInserter) that corrects CFA calculation rule for a basic block if needed. That means that additional CFI instructions get inserted 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. Patch by Violeta Vukobrat. Differential Revision: https://reviews.llvm.org/D18046 llvm-svn: 306529
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