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* This reapplies r207235 with an additional bugfixes caught by the msanAdrian Prantl2014-04-251-20/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | buildbot - do not insert debug intrinsics before phi nodes. Debug info for optimized code: Support variables that are on the stack and described by DBG_VALUEs during their lifetime. Previously, when a variable was at a FrameIndex for any part of its lifetime, this would shadow all other DBG_VALUEs and only a single fbreg location would be emitted, which in fact is only valid for a small range and not the entire lexical scope of the variable. The included dbg-value-const-byref testcase demonstrates this. This patch fixes this by Local - emitting dbg.value intrinsics for allocas that are passed by reference - dropping all dbg.declares (they are now fully lowered to dbg.values) SelectionDAG - renamed constructors for SDDbgValue for better readability. - fix UserValue::match() to handle indirect values correctly - not inserting an MMI table entries for dbg.values that describe allocas. - lowering dbg.values that describe allocas into *indirect* DBG_VALUEs. CodeGenPrepare - leaving dbg.values for an alloca were they are (see comment) Other - regenerated/updated instcombine.ll testcase and included source rdar://problem/16679879 http://reviews.llvm.org/D3374 llvm-svn: 207269
* Revert "This reapplies r207130 with an additional testcase+and a missing ↵Adrian Prantl2014-04-251-19/+20
| | | | | | | | check for" This reverts commit 207235 to investigate msan buildbot breakage. llvm-svn: 207250
* This reapplies r207130 with an additional testcase+and a missing check forAdrian Prantl2014-04-251-20/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | AllocaInst that was missing in one location. Debug info for optimized code: Support variables that are on the stack and described by DBG_VALUEs during their lifetime. Previously, when a variable was at a FrameIndex for any part of its lifetime, this would shadow all other DBG_VALUEs and only a single fbreg location would be emitted, which in fact is only valid for a small range and not the entire lexical scope of the variable. The included dbg-value-const-byref testcase demonstrates this. This patch fixes this by Local - emitting dbg.value intrinsics for allocas that are passed by reference - dropping all dbg.declares (they are now fully lowered to dbg.values) SelectionDAG - renamed constructors for SDDbgValue for better readability. - fix UserValue::match() to handle indirect values correctly - not inserting an MMI table entries for dbg.values that describe allocas. - lowering dbg.values that describe allocas into *indirect* DBG_VALUEs. CodeGenPrepare - leaving dbg.values for an alloca were they are (see comment) Other - regenerated/updated instcombine.ll testcase and included source rdar://problem/16679879 http://reviews.llvm.org/D3374 llvm-svn: 207235
* Revert "This reapplies r207130 with an additional testcase+and a missing ↵Adrian Prantl2014-04-251-19/+20
| | | | | | | | check for" Typo in testcase. llvm-svn: 207166
* This reapplies r207130 with an additional testcase+and a missing check forAdrian Prantl2014-04-251-20/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | AllocaInst that was missing in one location. Debug info for optimized code: Support variables that are on the stack and described by DBG_VALUEs during their lifetime. Previously, when a variable was at a FrameIndex for any part of its lifetime, this would shadow all other DBG_VALUEs and only a single fbreg location would be emitted, which in fact is only valid for a small range and not the entire lexical scope of the variable. The included dbg-value-const-byref testcase demonstrates this. This patch fixes this by Local - emitting dbg.value intrinsics for allocas that are passed by reference - dropping all dbg.declares (they are now fully lowered to dbg.values) SelectionDAG - renamed constructors for SDDbgValue for better readability. - fix UserValue::match() to handle indirect values correctly - not inserting an MMI table entries for dbg.values that describe allocas. - lowering dbg.values that describe allocas into *indirect* DBG_VALUEs. CodeGenPrepare - leaving dbg.values for an alloca were they are (see comment) Other - regenerated/updated instcombine.ll testcase and included source rdar://problem/16679879 http://reviews.llvm.org/D3374 llvm-svn: 207165
* Revert "Debug info for optimized code: Support variables that are on the ↵Adrian Prantl2014-04-251-14/+13
| | | | | | | | stack and" This reverts commit 207130 for buildbot breakage. llvm-svn: 207162
* Debug info for optimized code: Support variables that are on the stack andAdrian Prantl2014-04-241-13/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | described by DBG_VALUEs during their lifetime. Previously, when a variable was at a FrameIndex for any part of its lifetime, this would shadow all other DBG_VALUEs and only a single fbreg location would be emitted, which in fact is only valid for a small range and not the entire lexical scope of the variable. The included dbg-value-const-byref testcase demonstrates this. This patch fixes this by Local - emitting dbg.value intrinsics for allocas that are passed by reference - dropping all dbg.declares (they are now fully lowered to dbg.values) SelectionDAG - renamed constructors for SDDbgValue for better readability. - fix UserValue::match() to handle indirect values correctly - not inserting an MMI table entries for dbg.values that describe allocas. - lowering dbg.values that describe allocas into *indirect* DBG_VALUEs. CodeGenPrepare - leaving dbg.values for an alloca were they are (see comment) Other - regenerated/updated instcombine-intrinsics testcase and included source rdar://problem/16679879 http://reviews.llvm.org/D3374 llvm-svn: 207130
* [Modules] Remove potential ODR violations by sinking the DEBUG_TYPEChandler Carruth2014-04-221-1/+2
| | | | | | | | | | | | define below all header includes in the lib/CodeGen/... tree. While the current modules implementation doesn't check for this kind of ODR violation yet, it is likely to grow support for it in the future. It also removes one layer of macro pollution across all the included headers. Other sub-trees will follow. llvm-svn: 206837
* Fix unnecessary line breakMatt Arsenault2014-04-211-4/+2
| | | | llvm-svn: 206772
* Patch by Vadim ChugunovYaron Keren2014-04-191-0/+5
| | | | | | | | | | | Win64 stack unwinder gets confused when execution flow "falls through" after a call to 'noreturn' function. This fixes the "missing epilogue" problem by emitting a trap instruction for IR 'unreachable' on x86_x64-pc-windows. A secondary use for it would be for anyone wanting to make double-sure that 'noreturn' functions, indeed, do not return. llvm-svn: 206684
* Convert SelectionDAG::getVTList to use ArrayRefCraig Topper2014-04-161-10/+10
| | | | llvm-svn: 206357
* Break PseudoSourceValue out of the Value hierarchy. It is now the root of ↵Nick Lewycky2014-04-151-5/+13
| | | | | | its own tree containing FixedStackPseudoSourceValue (which you can use isa/dyn_cast on) and MipsCallEntry (which you can't). Anything that needs to use either a PseudoSourceValue* and Value* is strongly encouraged to use a MachinePointerInfo instead. llvm-svn: 206255
* [C++11] More 'nullptr' conversion. In some cases just using a boolean check ↵Craig Topper2014-04-141-117/+117
| | | | | | instead of comparing to nullptr. llvm-svn: 206142
* Fix for PR 19261:Eric Christopher2014-04-031-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | llc doesn't generate nodes for unconditional fall-through branches for targets without FastISel implementation (X86 has it, but can be disabled by "-fast-isel=false") in SelectionDAGBuilder::visitBr(). So for line 4 in the following testcase 1: void foo(int i){ 2: switch(i){ 3: default: 4: break; 5: } 6: return; 7: } there is no corresponding line in .debug_line section, and a debugger cannot set a breakpoint at line 4. Fix this by always emitting a branch when we're not optimizing and add a testcase to ensure that there's code on every line we'd want to break. Patch by Daniil Fukalov. llvm-svn: 205529
* Avoid storing Twines.Benjamin Kramer2014-03-291-22/+19
| | | | | | While there nested ifs into a helper function. No functionality change. llvm-svn: 205108
* Add @llvm.clear_cache builtinRenato Golin2014-03-261-0/+2
| | | | | | | | | | | | | | | | | Implementing the LLVM part of the call to __builtin___clear_cache which translates into an intrinsic @llvm.clear_cache and is lowered by each target, either to a call to __clear_cache or nothing at all incase the caches are unified. Updating LangRef and adding some tests for the implemented architectures. Other archs will have to implement the method in case this builtin has to be compiled for it, since the default behaviour is to bail unimplemented. A Clang patch is required for the builtin to be lowered into the llvm intrinsic. This will be done next. llvm-svn: 204802
* remove a bunch of unused private methodsNuno Lopes2014-03-231-10/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | found with a smarter version of -Wunused-member-function that I'm playwing with. Appologies in advance if I removed someone's WIP code. include/llvm/CodeGen/MachineSSAUpdater.h | 1 include/llvm/IR/DebugInfo.h | 3 lib/CodeGen/MachineSSAUpdater.cpp | 10 -- lib/CodeGen/PostRASchedulerList.cpp | 1 lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | 10 -- lib/IR/DebugInfo.cpp | 12 -- lib/MC/MCAsmStreamer.cpp | 2 lib/Support/YAMLParser.cpp | 39 --------- lib/TableGen/TGParser.cpp | 16 --- lib/TableGen/TGParser.h | 1 lib/Target/AArch64/AArch64TargetTransformInfo.cpp | 9 -- lib/Target/ARM/ARMCodeEmitter.cpp | 12 -- lib/Target/ARM/ARMFastISel.cpp | 84 -------------------- lib/Target/Mips/MipsCodeEmitter.cpp | 11 -- lib/Target/Mips/MipsConstantIslandPass.cpp | 12 -- lib/Target/NVPTX/NVPTXISelDAGToDAG.cpp | 21 ----- lib/Target/NVPTX/NVPTXISelDAGToDAG.h | 2 lib/Target/PowerPC/PPCFastISel.cpp | 1 lib/Transforms/Instrumentation/AddressSanitizer.cpp | 2 lib/Transforms/Instrumentation/BoundsChecking.cpp | 2 lib/Transforms/Instrumentation/MemorySanitizer.cpp | 1 lib/Transforms/Scalar/LoopIdiomRecognize.cpp | 8 - lib/Transforms/Scalar/SCCP.cpp | 1 utils/TableGen/CodeEmitterGen.cpp | 2 24 files changed, 2 insertions(+), 261 deletions(-) llvm-svn: 204560
* Fix an assertion caused by using inline asm with indirect register inputs.Kevin Qin2014-03-211-1/+1
| | | | llvm-svn: 204425
* IR: add a second ordering operand to cmpxhg for failureTim Northover2014-03-111-4/+6
| | | | | | | | | | | | | | | The syntax for "cmpxchg" should now look something like: cmpxchg i32* %addr, i32 42, i32 3 acquire monotonic where the second ordering argument gives the required semantics in the case that no exchange takes place. It should be no stronger than the first ordering constraint and cannot be either "release" or "acq_rel" (since no store will have taken place). rdar://problem/15996804 llvm-svn: 203559
* [C++11] Add range based accessors for the Use-Def chain of a Value.Chandler Carruth2014-03-091-7/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This requires a number of steps. 1) Move value_use_iterator into the Value class as an implementation detail 2) Change it to actually be a *Use* iterator rather than a *User* iterator. 3) Add an adaptor which is a User iterator that always looks through the Use to the User. 4) Wrap these in Value::use_iterator and Value::user_iterator typedefs. 5) Add the range adaptors as Value::uses() and Value::users(). 6) Update *all* of the callers to correctly distinguish between whether they wanted a use_iterator (and to explicitly dig out the User when needed), or a user_iterator which makes the Use itself totally opaque. Because #6 requires churning essentially everything that walked the Use-Def chains, I went ahead and added all of the range adaptors and switched them to range-based loops where appropriate. Also because the renaming requires at least churning every line of code, it didn't make any sense to split these up into multiple commits -- all of which would touch all of the same lies of code. The result is still not quite optimal. The Value::use_iterator is a nice regular iterator, but Value::user_iterator is an iterator over User*s rather than over the User objects themselves. As a consequence, it fits a bit awkwardly into the range-based world and it has the weird extra-dereferencing 'operator->' that so many of our iterators have. I think this could be fixed by providing something which transforms a range of T&s into a range of T*s, but that *can* be separated into another patch, and it isn't yet 100% clear whether this is the right move. However, this change gets us most of the benefit and cleans up a substantial amount of code around Use and User. =] llvm-svn: 203364
* [Layering] Move DebugInfo.h into the IR library where its implementationChandler Carruth2014-03-061-1/+1
| | | | | | already lives. llvm-svn: 203046
* Check for dynamic allocas and inline asm that clobbers sp before buildingHans Wennborg2014-03-051-6/+4
| | | | | | | | | | | | | | | | | | | selection dag (PR19012) In X86SelectionDagInfo::EmitTargetCodeForMemcpy we check with MachineFrameInfo to make sure that ESI isn't used as a base pointer register before we choose to emit rep movs (which clobbers esi). The problem is that MachineFrameInfo wouldn't know about dynamic allocas or inline asm that clobbers the stack pointer until SelectionDAGBuilder has encountered them. This patch fixes the problem by checking for such things when building the FunctionLoweringInfo. Differential Revision: http://llvm-reviews.chandlerc.com/D2954 llvm-svn: 202930
* [C++11] Replace llvm::next and llvm::prior with std::next and std::prev.Benjamin Kramer2014-03-021-1/+1
| | | | | | Remove the old functions. llvm-svn: 202636
* Rename a few more DataLayout variables from TD to DL.Rafael Espindola2014-02-211-14/+14
| | | | llvm-svn: 201870
* [DAG] Fix the recognition of opaque constants in the SelectionDAGBuilder.Juergen Ributzka2014-02-131-3/+7
| | | | | | | | | | | This fix checks the original LLVM IR node to identify opaque constants by looking for the bitcast-constant pattern. Originally we looked at the generated SDNode, but this might lead to incorrect results. The SDNode could have been generated by an constant expression that was folded to a constant. This fixes <rdar://problem/16050719> llvm-svn: 201291
* [Stackmaps] Improve the stackmap lowering code in the SelectionDAGBuilder.Juergen Ributzka2014-02-121-33/+33
| | | | | | | | | | We are now no longer relying on the target-specific call lowering implementation to lower a stackmap intrinsic call. Instead we perform the call lowering in a target-independent way directly in the stackmap lowering code. This simplifies the code and removes the need to fixup the code after the target-specific call lowering. llvm-svn: 201263
* [Stackmaps] Fix the ID type to be i64 also for stackmaps (as we claim in the ↵Juergen Ributzka2014-02-121-6/+7
| | | | | | | | | | | documenation) The ID type for the stackmap and patchpoint intrinsics are in both cases i64. This fixes an zero extend in the SelectionDAGBuilder that still used i32. This also updates the target independent instructions STACKMAP and PATCHPOINT to use the correct type. llvm-svn: 201262
* Pass address space to allowsUnalignedMemoryAccessesMatt Arsenault2014-02-051-1/+5
| | | | llvm-svn: 200888
* Implement inalloca codegen for x86 with the new inalloca designReid Kleckner2014-01-311-2/+24
| | | | | | | | | | | | | | | | Calls with inalloca are lowered by skipping all stores for arguments passed in memory and the initial stack adjustment to allocate argument memory. Now the frontend is responsible for the memory layout, and the backend doesn't have to do any work. As a result these changes are pretty minimal. Reviewers: echristo Differential Revision: http://llvm-reviews.chandlerc.com/D2637 llvm-svn: 200596
* PGO branch weight: update edge weights in SelectionDAGBuilder.Manman Ren2014-01-311-10/+61
| | | | | | | | | | | | | | | | When converting from "or + br" to two branches, or converting from "and + br" to two branches, we correctly update the edge weights of the two branches. The previous attempt at r200431 was reverted at r200434 because of two testing case failures. I modified my patch a little, but forgot to re-run "make check-all". Testing case CodeGen/ARM/lsr-unfolded-offset.ll is updated because of the patch's impact on branch probability which causes changes in spill placement. llvm-svn: 200502
* Revert r200431 due to bot failures.Manman Ren2014-01-301-61/+10
| | | | llvm-svn: 200434
* PGO branch weight: update edge weights in SelectionDAGBuilder.Manman Ren2014-01-301-10/+61
| | | | | | | | When converting from "or + br" to two branches, or converting from "and + br" to two branches, we correctly update the edge weights of the two branches. llvm-svn: 200431
* Revert "Revert "Add Constant Hoisting Pass" (r200034)"Juergen Ributzka2014-01-251-0/+3
| | | | | | | This reverts commit r200058 and adds the using directive for ARMTargetTransformInfo to silence two g++ overload warnings. llvm-svn: 200062
* Revert "Add Constant Hoisting Pass" (r200034)Hans Wennborg2014-01-251-3/+0
| | | | | | | | | | | | | | | This commit caused -Woverloaded-virtual warnings. The two new TargetTransformInfo::getIntImmCost functions were only added to the superclass, and to the X86 subclass. The other targets were not updated, and the warning highlighted this by pointing out that e.g. ARMTTI::getIntImmCost was hiding the two new getIntImmCost variants. We could pacify the warning by adding "using TargetTransformInfo::getIntImmCost" to the various subclasses, or turning it off, but I suspect that it's wrong to leave the functions unimplemnted in those targets. The default implementations return TCC_Free, which I don't think is right e.g. for ARM. llvm-svn: 200058
* Add Constant Hoisting PassJuergen Ributzka2014-01-241-0/+3
| | | | | | | | Retry commit r200022 with a fix for the build bot errors. Constant expressions have (unlike instructions) module scope use lists and therefore may have users in different functions. The fix is to simply ignore these out-of-function uses. llvm-svn: 200034
* Revert "Add Constant Hoisting Pass"Juergen Ributzka2014-01-241-3/+0
| | | | | | This reverts commit r200022 to unbreak the build bots. llvm-svn: 200024
* Add Constant Hoisting PassJuergen Ributzka2014-01-241-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This pass identifies expensive constants to hoist and coalesces them to better prepare it for SelectionDAG-based code generation. This works around the limitations of the basic-block-at-a-time approach. First it scans all instructions for integer constants and calculates its cost. If the constant can be folded into the instruction (the cost is TCC_Free) or the cost is just a simple operation (TCC_BASIC), then we don't consider it expensive and leave it alone. This is the default behavior and the default implementation of getIntImmCost will always return TCC_Free. If the cost is more than TCC_BASIC, then the integer constant can't be folded into the instruction and it might be beneficial to hoist the constant. Similar constants are coalesced to reduce register pressure and materialization code. When a constant is hoisted, it is also hidden behind a bitcast to force it to be live-out of the basic block. Otherwise the constant would be just duplicated and each basic block would have its own copy in the SelectionDAG. The SelectionDAG recognizes such constants as opaque and doesn't perform certain transformations on them, which would create a new expensive constant. This optimization is only applied to integer constants in instructions and simple (this means not nested) constant cast experessions. For example: %0 = load i64* inttoptr (i64 big_constant to i64*) Reviewed by Eric llvm-svn: 200022
* Fix non-deterministic SDNodeOrder-dependent codegenNico Rieck2014-01-121-0/+1
| | | | | | | Reset SelectionDAGBuilder's SDNodeOrder to ensure deterministic code generation. llvm-svn: 199050
* [stackprotector] Use analysis from the StackProtector pass for stack layout ↵Josh Magee2013-12-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | in PEI a nd LocalStackSlot passes. This changes the MachineFrameInfo API to use the new SSPLayoutKind information produced by the StackProtector pass (instead of a boolean flag) and updates a few pass dependencies (to preserve the SSP analysis). The stack layout follows the same approach used prior to this change - i.e., only LargeArray stack objects will be placed near the canary and everything else will be laid out normally. After this change, structures containing large arrays will also be placed near the canary - a case previously missed by the old implementation. Out of tree targets will need to update their usage of MachineFrameInfo::CreateStackObject to remove the MayNeedSP argument. The next patch will implement the rules for sspstrong and sspreq. The end goal is to support ssp-strong stack layout rules. WIP. Differential Revision: http://llvm-reviews.chandlerc.com/D2158 llvm-svn: 197653
* [Stackmap] Liveness Analysis PassJuergen Ributzka2013-12-141-0/+6
| | | | | | | | | | | | | | | | | | | | This optional register liveness analysis pass can be enabled with either -enable-stackmap-liveness, -enable-patchpoint-liveness, or both. The pass traverses each basic block in a machine function. For each basic block the instructions are processed in reversed order and if a patchpoint or stackmap instruction is encountered the current live-out register set is encoded as a register mask and attached to the instruction. Later on during stackmap generation the live-out register mask is processed and also emitted as part of the stackmap. This information is optional and intended for optimization purposes only. This will enable a client of the stackmap to reason about the registers it can use and which registers need to be preserved. Reviewed by Andy llvm-svn: 197317
* Revert "Liveness Analysis Pass"Andrew Trick2013-12-131-6/+0
| | | | | | | | | | | | | | This reverts commit r197254. This was an accidental merge of Juergen's patch. It will be checked in shortly, but wasn't meant to go in quite yet. Conflicts: include/llvm/CodeGen/StackMaps.h lib/CodeGen/StackMaps.cpp test/CodeGen/X86/stackmap-liveness.ll llvm-svn: 197260
* Grow the stackmap/patchpoint format to hold 64-bit IDs.Andrew Trick2013-12-131-2/+2
| | | | llvm-svn: 197255
* Liveness Analysis PassAndrew Trick2013-12-131-0/+6
| | | | llvm-svn: 197254
* SelectionDAG: Fix a typo.Benjamin Kramer2013-12-111-1/+1
| | | | | | Found by "cppcheck". PR18208. llvm-svn: 197047
* Reland "Fix miscompile of MS inline assembly with stack realignment"Reid Kleckner2013-12-101-1/+9
| | | | | | | | | | | This re-lands commit r196876, which was reverted in r196879. The tests have been fixed to pass on platforms with a stack alignment larger than 4. Update to clang side tests will land shortly. llvm-svn: 196939
* Add TargetLowering::prepareVolatileOrAtomicLoadRichard Sandiford2013-12-101-1/+6
| | | | | | | | | | | | | | | | | One unusual feature of the z architecture is that the result of a previous load can be reused indefinitely for subsequent loads, even if a cache-coherent store to that location is performed by another CPU. A special serializing instruction must be used if you want to force a load to be reattempted. Since volatile loads are not supposed to be omitted in this way, we should insert a serializing instruction before each such load. The same goes for atomic loads. The patch implements this at the IR->DAG boundary, in a similar way to atomic fences. It is a no-op for targets other than SystemZ. llvm-svn: 196905
* Revert "Fix miscompile of MS inline assembly with stack realignment"Reid Kleckner2013-12-101-9/+1
| | | | | | | This reverts commit r196876. Its tests failed on the bots, so I'll figure it out tomorrow. llvm-svn: 196879
* Fix miscompile of MS inline assembly with stack realignmentReid Kleckner2013-12-101-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | For stack frames requiring realignment, three pointers may be needed: - ebp to address incoming arguments - esi (could be any callee-saved register) to address locals - esp to address outgoing arguments We would use esi unconditionally without verifying that it did not conflict with inline assembly. This change doesn't do the verification, it simply emits a fatal error on functions that use stack realignment, dynamic SP adjustments, and inline assembly. Because stack realignment is common on Windows, we also no longer assume that MS inline assembly clobbers esp. Instead, we analyze the inline instructions for implicit definitions and check if esp is there. If so, we require the use of a base pointer and consider it in the condition above. Mostly fixes PR16830, but we could try harder to find a non-conflicting base pointer. Reviewers: sunfish Differential Revision: http://llvm-reviews.chandlerc.com/D1317 llvm-svn: 196876
* Try harder to get a consistent floating point results.Rafael Espindola2013-12-051-1/+1
| | | | | | | | | This just extends the existing hack. It should be enough to get a reproducible bootstrap on 32 bits. I will open a bug to track getting a real fix for this. llvm-svn: 196462
* StackMap: Implement support for DirectMemRefOp.Andrew Trick2013-11-261-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | A Direct stack map location records the address of frame index. This address is itself the value that the runtime requested. This differs from IndirectMemRefOp locations, which refer to a stack locations from which the requested values must be loaded. Direct locations can directly communicate the address if an alloca, while IndirectMemRefOp handle register spills. For example: entry: %a = alloca i64... llvm.experimental.stackmap(i32 <ID>, i32 <shadowBytes>, i64* %a) Since both the alloca and stackmap intrinsic are in the entry block, and the intrinsic takes the address of the alloca, the runtime can assume that LLVM will not substitute alloca with any intervening value. This must be verified by the runtime by checking that the stack map's location is a Direct location type. The runtime can then determine the alloca's relative location on the stack immediately after compilation, or at any time thereafter. This differs from Register and Indirect locations, because the runtime can only read the values in those locations when execution reaches the instruction address of the stack map. llvm-svn: 195712
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