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2013-04-23Add some constraints to use of 'returned':Stephen Lin
1) Disallow 'returned' on parameter that is also 'sret' (no sensible semantics, as far as I can tell). 2) Conservatively disallow tail calls through 'returned' parameters that also are 'zext' or 'sext' (for consistency with treatment of other zero-extending and sign-extending operations in tail call position detection...can be revised later to handle situations that can be determined to be safe). This is a new attribute that is not yet used, so there is no impact. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180118 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-22Remove unused DwarfSectionOffsetDirective stringMatt Arsenault
The value isn't actually used, and setting it emits a COFF specific directive. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180064 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-22Move C++ code out of the C headers and into either C++ headersEric Christopher
or the C++ files themselves. This enables people to use just a C compiler to interoperate with LLVM. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180063 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-22Optimize MachineBasicBlock::getSymbol by caching the symbol. Since the symbolEli Bendersky
name computation is expensive, this helps save about 25% of the time spent in this function. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180049 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-22Clarify that llvm.used can contain aliases.Rafael Espindola
Also add a check for llvm.used in the verifier and simplify clients now that they can assume they have a ConstantArray. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180019 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-22Tidy.Eric Christopher
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180000 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-22Update comment. Whitespace.Eric Christopher
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179999 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-22Revert "Revert "PR14606: debug info imported_module support""David Blaikie
This reverts commit r179840 with a fix to test/DebugInfo/two-cus-from-same-file.ll I'm not sure why that test only failed on ARM & MIPS and not X86 Linux, even though the debug info was clearly invalid on all of them, but this ought to fix it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179996 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-21Legalize vector truncates by parts rather than just splitting.Jim Grosbach
Rather than just splitting the input type and hoping for the best, apply a bit more cleverness. Just splitting the types until the source is legal often leads to an illegal result time, which is then widened and a scalarization step is introduced which leads to truly horrible code generation. With the loop vectorizer, these sorts of operations are much more common, and so it's worth extra effort to do them well. Add a legalization hook for the operands of a TRUNCATE node, which will be encountered after the result type has been legalized, but if the operand type is still illegal. If simple splitting of both types ends up with the result type of each half still being legal, just do that (v16i16 -> v16i8 on ARM, for example). If, however, that would result in an illegal result type (v8i32 -> v8i8 on ARM, for example), we can get more clever with power-two vectors. Specifically, split the input type, but also widen the result element size, then concatenate the halves and truncate again. For example on ARM, To perform a "%res = v8i8 trunc v8i32 %in" we transform to: %inlo = v4i32 extract_subvector %in, 0 %inhi = v4i32 extract_subvector %in, 4 %lo16 = v4i16 trunc v4i32 %inlo %hi16 = v4i16 trunc v4i32 %inhi %in16 = v8i16 concat_vectors v4i16 %lo16, v4i16 %hi16 %res = v8i8 trunc v8i16 %in16 This allows instruction selection to generate three VMOVN instructions instead of a sequences of moves, stores and loads. Update the ARMTargetTransformInfo to take this improved legalization into account. Consider the simplified IR: define <16 x i8> @test1(<16 x i32>* %ap) { %a = load <16 x i32>* %ap %tmp = trunc <16 x i32> %a to <16 x i8> ret <16 x i8> %tmp } define <8 x i8> @test2(<8 x i32>* %ap) { %a = load <8 x i32>* %ap %tmp = trunc <8 x i32> %a to <8 x i8> ret <8 x i8> %tmp } Previously, we would generate the truly hideous: .syntax unified .section __TEXT,__text,regular,pure_instructions .globl _test1 .align 2 _test1: @ @test1 @ BB#0: push {r7} mov r7, sp sub sp, sp, #20 bic sp, sp, #7 add r1, r0, #48 add r2, r0, #32 vld1.64 {d24, d25}, [r0:128] vld1.64 {d16, d17}, [r1:128] vld1.64 {d18, d19}, [r2:128] add r1, r0, #16 vmovn.i32 d22, q8 vld1.64 {d16, d17}, [r1:128] vmovn.i32 d20, q9 vmovn.i32 d18, q12 vmov.u16 r0, d22[3] strb r0, [sp, #15] vmov.u16 r0, d22[2] strb r0, [sp, #14] vmov.u16 r0, d22[1] strb r0, [sp, #13] vmov.u16 r0, d22[0] vmovn.i32 d16, q8 strb r0, [sp, #12] vmov.u16 r0, d20[3] strb r0, [sp, #11] vmov.u16 r0, d20[2] strb r0, [sp, #10] vmov.u16 r0, d20[1] strb r0, [sp, #9] vmov.u16 r0, d20[0] strb r0, [sp, #8] vmov.u16 r0, d18[3] strb r0, [sp, #3] vmov.u16 r0, d18[2] strb r0, [sp, #2] vmov.u16 r0, d18[1] strb r0, [sp, #1] vmov.u16 r0, d18[0] strb r0, [sp] vmov.u16 r0, d16[3] strb r0, [sp, #7] vmov.u16 r0, d16[2] strb r0, [sp, #6] vmov.u16 r0, d16[1] strb r0, [sp, #5] vmov.u16 r0, d16[0] strb r0, [sp, #4] vldmia sp, {d16, d17} vmov r0, r1, d16 vmov r2, r3, d17 mov sp, r7 pop {r7} bx lr .globl _test2 .align 2 _test2: @ @test2 @ BB#0: push {r7} mov r7, sp sub sp, sp, #12 bic sp, sp, #7 vld1.64 {d16, d17}, [r0:128] add r0, r0, #16 vld1.64 {d20, d21}, [r0:128] vmovn.i32 d18, q8 vmov.u16 r0, d18[3] vmovn.i32 d16, q10 strb r0, [sp, #3] vmov.u16 r0, d18[2] strb r0, [sp, #2] vmov.u16 r0, d18[1] strb r0, [sp, #1] vmov.u16 r0, d18[0] strb r0, [sp] vmov.u16 r0, d16[3] strb r0, [sp, #7] vmov.u16 r0, d16[2] strb r0, [sp, #6] vmov.u16 r0, d16[1] strb r0, [sp, #5] vmov.u16 r0, d16[0] strb r0, [sp, #4] ldm sp, {r0, r1} mov sp, r7 pop {r7} bx lr Now, however, we generate the much more straightforward: .syntax unified .section __TEXT,__text,regular,pure_instructions .globl _test1 .align 2 _test1: @ @test1 @ BB#0: add r1, r0, #48 add r2, r0, #32 vld1.64 {d20, d21}, [r0:128] vld1.64 {d16, d17}, [r1:128] add r1, r0, #16 vld1.64 {d18, d19}, [r2:128] vld1.64 {d22, d23}, [r1:128] vmovn.i32 d17, q8 vmovn.i32 d16, q9 vmovn.i32 d18, q10 vmovn.i32 d19, q11 vmovn.i16 d17, q8 vmovn.i16 d16, q9 vmov r0, r1, d16 vmov r2, r3, d17 bx lr .globl _test2 .align 2 _test2: @ @test2 @ BB#0: vld1.64 {d16, d17}, [r0:128] add r0, r0, #16 vld1.64 {d18, d19}, [r0:128] vmovn.i32 d16, q8 vmovn.i32 d17, q9 vmovn.i16 d16, q8 vmov r0, r1, d16 bx lr git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179989 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-21Tidy up comment grammar.Jim Grosbach
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179986 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20Remove unused ShouldFoldAtomicFences flag.Tim Northover
I think it's almost impossible to fold atomic fences profitably under LLVM/C++11 semantics. As a result, this is now unused and just cluttering up the target interface. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179940 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20Remove unused MEMBARRIER DAG node; it's been replaced by ATOMIC_FENCE.Tim Northover
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179939 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20Add CodeGen support for functions that always return arguments via a new ↵Stephen Lin
parameter attribute 'returned', which is taken advantage of in target-independent tail call opportunity detection and in ARM call lowering (when placed on an integral first parameter). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179925 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20Allow tail call opportunity detection through nested and/or multiple ↵Stephen Lin
iterations of extractelement/insertelement indirection git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179924 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-19Simplify the code in FastISel::tryToFoldLoad, add an assertion and fix a ↵Eli Bendersky
comment. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179908 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-19Move TryToFoldFastISelLoad to FastISel, where it belongs. In general, I'mEli Bendersky
trying to move as much FastISel logic as possible out of the main path in SelectionDAGISel - intermixing them just adds confusion. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179902 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-19ArrayRefize getMachineNode(). No functionality change.Michael Liao
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179901 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-19Add an MRI::verifyUseLists() function.Jakob Stoklund Olesen
This checks the sanity of the register use lists in the MI intermediate representation. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179895 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-19Use dbgs() consistently for -debug printoutsEli Bendersky
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179894 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-19Revert "PR14606: debug info imported_module support"Eric Christopher
This reverts commit r179836 as it seems to have caused test failures. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179840 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-19PR14606: debug info imported_module supportDavid Blaikie
Adding another CU-wide list, in this case of imported_modules (since they should be relatively rare, it seemed better to add a list where each element had a "context" value, rather than add a (usually empty) list to every scope). This takes care of DW_TAG_imported_module, but to fully address PR14606 we'll need to expand this to cover DW_TAG_imported_declaration too. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179836 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-19Add some more stats for fast isel vs. SelectionDAG, w.r.t lowering functionEli Bendersky
arguments in entry BBs. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179824 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-17Add support for subsections to the ELF assembler. Fixes PR8717.Peter Collingbourne
Differential Revision: http://llvm-reviews.chandlerc.com/D598 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179725 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-15Replace uses of the deprecated std::auto_ptr with OwningPtr.Andy Gibbs
This is a rework of the broken parts in r179373 which were subsequently reverted in r179374 due to incompatibility with C++98 compilers. This version should be ok under C++98. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179520 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-14Document the decision to assume that the cost of floats is twice as much as ↵Nadav Rotem
integers. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179478 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-13MI-Sched: DEBUG formatting.Andrew Trick
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179452 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-13MI-Sched cleanup. If an instruction has no valid sched class, do not attempt ↵Andrew Trick
to check for a variant. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179451 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-13MI-Sched: schedule physreg copies.Andrew Trick
The register allocator expects minimal physreg live ranges. Schedule physreg copies accordingly. This is slightly tricky when they occur in the middle of the scheduling region. For now, this is handled by rescheduling the copy when its associated instruction is scheduled. Eventually we may instead bundle them, but only if we can preserve the bundles as parallel copies during regalloc. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179449 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-12CostModel: increase the default cost of supported floating point operations ↵Nadav Rotem
from 1 to two. Fixed a few tests that changes because now the cost of one insert + a vector operation on two doubles is lower than two scalar operations on doubles. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179413 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-12Revert broken pieces of r179373.Benjamin Kramer
You can't copy an OwningPtr, and move semantics aren't available in C++98. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179374 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-12Replace uses of the deprecated std::auto_ptr with OwningPtr.Andy Gibbs
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179373 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-12Don't disable block layout when forcing block alignment.Nadav Rotem
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179355 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-12Add a flag to align all basic blocks in the function.Nadav Rotem
When debugging performance regressions we often ask ourselves if the regression that we see is due to poor isel/sched/ra or due to some micro-architetural problem. When comparing two code sequences one good way to rule out front-end bottlenecks (and other the issues) is to force code alignment. This pass adds a flag that forces the alignment of all of the basic blocks in the program. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179353 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-11Add braces around || in && to pacify GCC.Benjamin Kramer
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179275 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-10Manually remove successors in if conversion when CopyAndPredicateBlock is usedHal Finkel
In the simple and triangle if-conversion cases, when CopyAndPredicateBlock is used because the to-be-predicated block has other predecessors, we need to explicitly remove the old copied block from the successors list. Normally if conversion relies on TII->AnalyzeBranch combined with BB->CorrectExtraCFGEdges to cleanup the successors list, but if the predicated block contained an un-analyzable branch (such as a now-predicated return), then this will fail. These extra successors were causing a problem on PPC because it was causing later passes (such as PPCEarlyReturm) to leave dead return-only basic blocks in the code. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179227 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-10Generalize the PassConfig API and remove addFinalizeRegAlloc().Andrew Trick
The target hooks are getting out of hand. What does it mean to run before or after regalloc anyway? Allowing either Pass* or AnalysisID pass identification should make it much easier for targets to use the substitutePass and insertPass APIs, and create less need for badly named target hooks. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179140 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-09The .dwo section shouldn't contain the unrelocated values (andEric Christopher
therefore not at all) of the pc or statement list. We also don't need to emit the compilation dir so save so space and time and don't bother. Fix up the testcase accordingly and verify that we don't emit the attributes or the items that they use. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179114 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-09DAGCombiner: Fold a shuffle on CONCAT_VECTORS into a new CONCAT_VECTORS if ↵Benjamin Kramer
possible. This pattern occurs in SROA output due to the way vector arguments are lowered on ARM. The testcase from PR15525 now compiles into this, which is better than the code we got with the old scalarrepl: _Store: ldr.w r9, [sp] vmov d17, r3, r9 vmov d16, r1, r2 vst1.8 {d16, d17}, [r0] bx lr Differential Revision: http://llvm-reviews.chandlerc.com/D647 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179106 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-07DW_FORM_sec_offset should be a relocation on platforms that useEric Christopher
a relocation across sections. Do this for DW_AT_stmt list in the skeleton CU and check the relocations in the debug_info section. Add a FIXME for multiple CUs. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178969 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-06typoNadav Rotem
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178949 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-06Dwarf: use utostr on CUID to append to SmallString.Manman Ren
We used to do "SmallString += CUID", which is incorrect, since CUID will be truncated to a char. rdar://problem/13573833 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178941 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-05Reapply r178845 with fix - Fix bug in PEI's virtual-register scavengingHal Finkel
This fixes PEI as previously described, but correctly handles the case where the instruction defining the virtual register to be scavenged is the first in the block. Arnold provided me with a bugpoint-reduced test case, but even that seems too large to use as a regression test. If I'm successful in cleaning it up then I'll commit that as well. Original commit message: This change fixes a bug that I introduced in r178058. After a register is scavenged using one of the available spills slots the instruction defining the virtual register needs to be moved to after the spill code. The scavenger has already processed the defining instruction so that registers killed by that instruction are available for definition in that same instruction. Unfortunately, after this, the scavenger needs to iterate through the spill code and then visit, again, the instruction that defines the now-scavenged register. In order to avoid confusion, the register scavenger needs the ability to 'back up' through the spill code so that it can again process the instructions in the appropriate order. Prior to this fix, once the scavenger reached the just-moved instruction, it would assert if it killed any registers because, having already processed the instruction, it believed they were undefined. Unfortunately, I don't yet have a small test case. Thanks to Pranav Bhandarkar for diagnosing the problem and testing this fix. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178919 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-05Use the target options specified on a function to reset the back-end.Bill Wendling
During LTO, the target options on functions within the same Module may change. This would necessitate resetting some of the back-end. Do this for X86, because it's a Friday afternoon. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178917 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-05Revert r178845 - Fix bug in PEI's virtual-register scavengingHal Finkel
Reverting because this breaks one of the LTO builders. Original commit message: This change fixes a bug that I introduced in r178058. After a register is scavenged using one of the available spills slots the instruction defining the virtual register needs to be moved to after the spill code. The scavenger has already processed the defining instruction so that registers killed by that instruction are available for definition in that same instruction. Unfortunately, after this, the scavenger needs to iterate through the spill code and then visit, again, the instruction that defines the now-scavenged register. In order to avoid confusion, the register scavenger needs the ability to 'back up' through the spill code so that it can again process the instructions in the appropriate order. Prior to this fix, once the scavenger reached the just-moved instruction, it would assert if it killed any registers because, having already processed the instruction, it believed they were undefined. Unfortunately, I don't yet have a small test case. Thanks to Pranav Bhandarkar for diagnosing the problem and testing this fix. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178916 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-05Fix bug in PEI's virtual-register scavengingHal Finkel
This change fixes a bug that I introduced in r178058. After a register is scavenged using one of the available spills slots the instruction defining the virtual register needs to be moved to after the spill code. The scavenger has already processed the defining instruction so that registers killed by that instruction are available for definition in that same instruction. Unfortunately, after this, the scavenger needs to iterate through the spill code and then visit, again, the instruction that defines the now-scavenged register. In order to avoid confusion, the register scavenger needs the ability to 'back up' through the spill code so that it can again process the instructions in the appropriate order. Prior to this fix, once the scavenger reached the just-moved instruction, it would assert if it killed any registers because, having already processed the instruction, it believed they were undefined. Unfortunately, I don't yet have a small test case. Thanks to Pranav Bhandarkar for diagnosing the problem and testing this fix. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178845 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-05RegisterPressure heuristics currently require signed comparisons.Andrew Trick
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178823 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-05Disable DFSResult for ConvergingScheduler.Andrew Trick
For now, just save the compile time since the ConvergingScheduler heuristics don't use this analysis. We'll probably enable it later after compile-time investigation. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178822 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-05MachineScheduler: format DEBUG output.Andrew Trick
I'm getting more serious about tuning and enabling on x86/ARM. Start by making the trace readable. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178821 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-04CostModel: Add parameter to instruction cost to further classify operand valuesArnold Schwaighofer
On certain architectures we can support efficient vectorized version of instructions if the operand value is uniform (splat) or a constant scalar. An example of this is a vector shift on x86. We can efficiently support for (i = 0 ; i < ; i += 4) w[0:3] = v[0:3] << <2, 2, 2, 2> but not for (i = 0; i < ; i += 4) w[0:3] = v[0:3] << x[0:3] This patch adds a parameter to getArithmeticInstrCost to further qualify operand values as uniform or uniform constant. Targets can then choose to return a different cost for instructions with such operand values. A follow-up commit will test this feature on x86. radar://13576547 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178807 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-04Debug Info: revert 178722 for now.Manman Ren
There is a difference for FORM_ref_addr between DWARF 2 and DWARF 3+. Since Eric is against guarding DWARF 2 ref_addr with DarwinGDBCompat, we are still in discussion on how to handle this. The correct solution is to update our header to say version 4 instead of version 2 and update tool chains as well. rdar://problem/13559431 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178806 91177308-0d34-0410-b5e6-96231b3b80d8