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* [ARM,MVE] Intrinsics for partial-overwrite imm shifts.Simon Tatham2020-01-081-4/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This batch of intrinsics covers two sets of immediate shift instructions, which have in common that they only overwrite part of their output register and so they need an extra input giving its previous value. The VSLI and VSRI instructions shift each lane of the input vector left or right just as if they were normal immediate VSHL/VSHR, but then they only overwrite the output bits that correspond to actual shifted bits of the input. So VSLI will leave the low n bits of each output lane unchanged, and VSRI the same with the top n bits. The V[Q][R]SHR[U]N family are all narrowing shifts: they take an input vector of 2n-bit integers, shift each lane right by a constant, and then narrowing the shifted result to only n bits. So they only overwrite half of the n-bit lanes in the output register, and the B/T suffix indicates whether it's the bottom or top half of each 2n-bit lane. I've implemented the whole of the latter family using a single IR intrinsic `vshrn`, which takes a lot of i32 parameters indicating which instruction it expands to (by specifying signedness of the input and output types, whether it saturates and/or rounds, etc). Reviewers: dmgreen, MarkMurrayARM, miyuki, ostannard Reviewed By: dmgreen Subscribers: kristof.beyls, hiraditya, cfe-commits, llvm-commits Tags: #clang, #llvm Differential Revision: https://reviews.llvm.org/D72328
* [ARM,MVE] Support -ve offsets in gather-load intrinsics.Simon Tatham2020-01-061-2/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: The ACLE intrinsics with `gather_base` or `scatter_base` in the name are wrappers on the MVE load/store instructions that take a vector of base addresses and an immediate offset. The immediate offset can be up to 127 times the alignment unit, and it can be positive or negative. At the MC layer, we got that right. But in the Sema error checking for the wrapping intrinsics, the offset was erroneously constrained to be positive. To fix this I've adjusted the `imm_mem7bit` class in the Tablegen that defines the intrinsics. But that causes integer literals like `0xfffffffffffffe04` to appear in the autogenerated calls to `SemaBuiltinConstantArgRange`, which provokes a compiler warning because that's out of the non-overflowing range of an `int64_t`. So I've also tweaked `MveEmitter` to emit that as `-0x1fc` instead. Updated the tests of the Sema checks themselves, and also adjusted a random sample of the CodeGen tests to actually use negative offsets and prove they get all the way through code generation without causing a crash. Reviewers: dmgreen, miyuki, MarkMurrayARM Reviewed By: dmgreen Subscribers: kristof.beyls, cfe-commits, llvm-commits Tags: #clang, #llvm Differential Revision: https://reviews.llvm.org/D72268
* [ARM][MVE] Add intrinsics for immediate shifts. (reland)Simon Tatham2019-12-111-32/+51
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds the family of `vshlq_n` and `vshrq_n` ACLE intrinsics, which shift every lane of a vector left or right by a compile-time immediate. They mostly work by expanding to the IR `shl`, `lshr` and `ashr` operations, with their second operand being a vector splat of the immediate. There's a fiddly special case, though. ACLE specifies that the immediate in `vshrq_n` can take values up to //and including// the bit size of the vector lane. But LLVM IR thinks that shifting right by the full size of the lane is UB, and feels free to replace the `lshr` with an `undef` half way through the optimization pipeline. Hence, to keep this legal in source code, I have to detect it at codegen time. Logical (unsigned) right shifts by the element size are handled by simply emitting the zero vector; arithmetic ones are converted into a shift of one bit less, which will always give the same output. In order to do that check, I also had to enhance the tablegen MveEmitter so that it can cope with converting a builtin function's operand into a bare integer to pass to a code-generating subfunction. Previously the only bare integers it knew how to handle were flags generated from within `arm_mve.td`. Reviewers: dmgreen, miyuki, MarkMurrayARM, ostannard Reviewed By: dmgreen, MarkMurrayARM Subscribers: echristo, hokein, rdhindsa, kristof.beyls, hiraditya, cfe-commits, llvm-commits Tags: #clang, #llvm Differential Revision: https://reviews.llvm.org/D71065
* Revert "[ARM][MVE] Add intrinsics for immediate shifts."Eric Christopher2019-12-091-52/+31
| | | | | | | | | | | | | | and two follow-on commits: one warning fix and one functionality. As it's breaking at least the lto bot: http://lab.llvm.org:8011/builders/clang-with-lto-ubuntu/builds/15132/steps/test-stage1-compiler/logs/stdio This reverts commits: 8d70f3c933a5b81a87a5ab1af0e3e98ee2cd7c67 ff4dceef9201c5ae3924e92f6955977f243ac71d d97b3e3e65cd77a81b39732af84a1a4229e95091
* [ARM][MVE][Intrinsics] Add VMULL[BT]Q_(INT|POLY) intrinsics.Mark Murray2019-12-091-5/+17
| | | | | | | | | | | | Summary: Add VMULL[BT]Q_(INT|POLY) intrinsics and unit tests. Reviewers: simon_tatham, ostannard, dmgreen Subscribers: kristof.beyls, hiraditya, cfe-commits, llvm-commits Tags: #clang, #llvm Differential Revision: https://reviews.llvm.org/D71066
* Fix the compiler warnings: "-Winconsistent-missing-override", ↵Haojian Wu2019-12-091-1/+1
| | | | | | "-Wunused-variable" for d97b3e3e65cd77a81b39732af84a1a4229e95091
* [ARM][MVE] Add intrinsics for immediate shifts.Simon Tatham2019-12-091-31/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: This adds the family of `vshlq_n` and `vshrq_n` ACLE intrinsics, which shift every lane of a vector left or right by a compile-time immediate. They mostly work by expanding to the IR `shl`, `lshr` and `ashr` operations, with their second operand being a vector splat of the immediate. There's a fiddly special case, though. ACLE specifies that the immediate in `vshrq_n` can take values up to //and including// the bit size of the vector lane. But LLVM IR thinks that shifting right by the full size of the lane is UB, and feels free to replace the `lshr` with an `undef` half way through the optimization pipeline. Hence, to keep this legal in source code, I have to detect it at codegen time. Logical (unsigned) right shifts by the element size are handled by simply emitting the zero vector; arithmetic ones are converted into a shift of one bit less, which will always give the same output. In order to do that check, I also had to enhance the tablegen MveEmitter so that it can cope with converting a builtin function's operand into a bare integer to pass to a code-generating subfunction. Previously the only bare integers it knew how to handle were flags generated from within `arm_mve.td`. Reviewers: dmgreen, miyuki, MarkMurrayARM, ostannard Reviewed By: MarkMurrayARM Subscribers: kristof.beyls, hiraditya, cfe-commits, llvm-commits Tags: #clang, #llvm Differential Revision: https://reviews.llvm.org/D71065
* [ARM,MVE] Add intrinsics to deal with predicates.Simon Tatham2019-12-021-7/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: This commit adds the `vpselq` intrinsics which take an MVE predicate word and select lanes from two vectors; the `vctp` intrinsics which create a tail predicate word suitable for processing the first m elements of a vector (e.g. in the last iteration of a loop); and `vpnot`, which simply complements a predicate word and is just syntactic sugar for the `~` operator. The `vctp` ACLE intrinsics are lowered to the IR intrinsics we've already added (and which D70592 just reorganized). I've filled in the missing isel rule for VCTP64, and added another set of rules to generate the predicated forms. I needed one small tweak in MveEmitter to allow the `unpromoted` type modifier to apply to predicates as well as integers, so that `vpnot` doesn't pointlessly convert its input integer to an `<n x i1>` before complementing it. Reviewers: ostannard, MarkMurrayARM, dmgreen Reviewed By: dmgreen Subscribers: kristof.beyls, hiraditya, cfe-commits, llvm-commits Tags: #clang, #llvm Differential Revision: https://reviews.llvm.org/D70485
* [ARM,MVE] Add intrinsics for vector get/set lane.Simon Tatham2019-11-151-6/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds the `vgetq_lane` and `vsetq_lane` families, to copy between a scalar and a specified lane of a vector. One of the new `vgetq_lane` intrinsics returns a `float16_t`, which causes a compile error if `%clang_cc1` doesn't get the option `-fallow-half-arguments-and-returns`. The driver passes that option to cc1 already, but I've had to edit all the explicit cc1 command lines in the existing MVE intrinsics tests. A couple of fixes are included for the code I wrote up front in MveEmitter to support lane-index immediates (and which nothing has tested until now): the type was wrong (`uint32_t` instead of `int`) and the range was off by one. I've also added a method of bypassing the default promotion to `i32` that is done by the MveEmitter code generation: it's sensible to promote short scalars like `i16` to `i32` if they're going to be passed to custom IR intrinsics representing a machine instruction operating on GPRs, but not if they're going to be passed to standard IR operations like `insertelement` which expect the exact type. Reviewers: ostannard, MarkMurrayARM, dmgreen Reviewed By: dmgreen Subscribers: kristof.beyls, cfe-commits Tags: #clang Differential Revision: https://reviews.llvm.org/D70188
* [ARM,MVE] Add intrinsics for 'administrative' vector operations.Simon Tatham2019-11-151-11/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | This batch of intrinsics includes lots of things that move vector data around or change its type without really affecting its value very much. It includes the `vreinterpretq` family (cast one vector type to another); `vuninitializedq` (create a vector of a given type with don't-care contents); and `vcreateq` (make a 128-bit vector out of two `uint64_t` halves). These are all implemented using completely standard IR that's already tested in existing LLVM unit tests, so I've just written a clang test to check the IR is correct, and left it at that. I've also added some richer infrastructure to the MveEmitter Tablegen backend, to make it specify the exact integer type of integer arguments passed to IR construction functions, and wrap those arguments in a `static_cast` in the autogenerated C++. That was necessary to prevent an overloading ambiguity when passing the integer literal `0` to `IRBuilder::CreateInsertElement`, because otherwise, it could mean either a null pointer `llvm::Value *` or a zero `uint64_t`. Reviewers: ostannard, MarkMurrayARM, dmgreen Subscribers: kristof.beyls, cfe-commits Tags: #clang Differential Revision: https://reviews.llvm.org/D70133
* [ARM,MVE] Add intrinsics for contiguous load/stores.Simon Tatham2019-11-131-21/+101
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds the ACLE intrinsics for all the MVE load and store instructions not already handled by D69791. These ones don't need new IR intrinsics, because they can be implemented in terms of standard LLVM IR constructions. Some of the load and store instructions access less than 128 bits of memory, sign/zero extending each value to a wider vector lane on load or truncating it on store. These are represented in IR by a load of a shorter vector followed by a zext/sext, and conversely, a trunc followed by a short store. Existing ISel patterns already recognize those combinations and turn them into the right MVE instructions. The predicated forms of all these instructions are represented in the same way, except that the ordinary load/store operation is replaced with the existing intrinsics @llvm.masked.{load,store}. These are currently only code-generated as predicated MVE load/store instructions if you give LLVM the `-enable-arm-maskedldst` option; so I've done that in the LLVM codegen test. When we make that the default, that option can be removed. In the Tablegen backend, I've had to add a handful of extra support features: * We need to be able to make clang::Address objects out of a pointer and an alignment (previously we only needed these when the user passed us an existing one). * We can now specify vector types that aren't 128 bits wide (for use in those intermediate values in IR), the parametrized type system can make one starting from two existing vector types (using the lane count of one and the element type of the other). * I've added support for code generation of pointer casts, and for specifying LLVM types as operands to IRBuilder operations (for zext and sext, though I think they'll come in useful again). * Now not all IR construction operations need to be specified as Builder.CreateFoo; some don't involve a Builder at all, and one passes it as a parameter to a tiny static helper function in CGBuiltin.cpp. Reviewers: ostannard, MarkMurrayARM, dmgreen Subscribers: kristof.beyls, cfe-commits, llvm-commits Tags: #clang, #llvm Differential Revision: https://reviews.llvm.org/D70088
* [ARM,MVE] Add intrinsics for gather/scatter load/stores.Simon Tatham2019-11-061-8/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds two new families of intrinsics, both of which are memory accesses taking a vector of locations to load from / store to. The vldrq_gather_base / vstrq_scatter_base intrinsics take a vector of base addresses, and an immediate offset to be added consistently to each one. vldrq_gather_offset / vstrq_scatter_offset take a scalar base address, and a vector of offsets to add to it. The 'shifted_offset' variants also multiply each offset by the element size type, so that the vector is effectively of array indices. At the IR level, these operations are represented by a single set of four IR intrinsics: {gather,scatter} × {base,offset}. The other details (signed/unsigned, shift, and memory element size as opposed to vector element size) are all specified by IR intrinsic polymorphism and immediate operands, because that made the selection job easier than making a huge family of similarly named intrinsics. I considered using the standard IR representations such as llvm.masked.gather, but they're not a good fit. In order to use llvm.masked.gather to represent a gather_offset load with element size smaller than a pointer, you'd have to expand the <8 x i16> vector of offsets into an <8 x i16*> vector of pointers, which would be split up during legalization, so you'd spend most of your time undoing the mess it had made. Also, ISel support for llvm.masked.gather would be easy enough in a trivial way (you can expand it into a gather-base load with a zero immediate offset), but instruction-selecting lots of fiddly idioms back into all the _other_ MVE load instructions would be much more work. So I think dedicated IR intrinsics are the more sensible approach, at least for the moment. On the clang tablegen side, I've added two new features to the Tablegen source accepted by MveEmitter: a 'CopyKind' type node for defining a type that varies with the parameter type (it lets you ask for an unsigned integer type of the same width as the parameter), and an 'unsignedflag' value node for passing an immediate IR operand which is 0 for a signed integer type or 1 for an unsigned one. That lets me write each kind of intrinsic just once and get all its subtypes and immediate arguments generated automatically. Also I've tweaked the handling of pointer-typed values in the code generation part of MveEmitter: they're generated as Address rather than Value (i.e. including an alignment) so that they can be given to the ordinary IR load and store operations, but I'd omitted the code to convert them back to Value when they're going to be used as an argument to an IR intrinsic. On the MC side, I've enhanced MVEVectorVTInfo so that it can tell you not only the full assembly-language suffix for a given vector type (like 's32' or 'u16') but also the numeric-only one used by store instructions (just '32' or '16'). Reviewers: dmgreen Subscribers: kristof.beyls, hiraditya, cfe-commits, llvm-commits Tags: #clang, #llvm Differential Revision: https://reviews.llvm.org/D69791
* [ARM,MVE] Integer-type nitpicks in MVE intrinsics.Simon Tatham2019-11-061-0/+10
| | | | | | | | | | | | | | | | | | | | | A few integer types in the ACLE definitions of MVE intrinsics are given as 'int' or 'unsigned' instead of <stdint.h> fixed-size types like uint32_t. Usually these are the ones where the size isn't that important, such as immediate offsets in loads (which have a range limited by the instruction encoding) or the carry flag in vadcq which can only be 0 or 1 anyway. With this change, <arm_mve.h> follows that exact type naming, so that the function prototypes look identical to the ones in ACLE, instead of replacing int and unsigned with int32_t and uint32_t. Reviewers: dmgreen Subscribers: kristof.beyls, cfe-commits Tags: #clang Differential Revision: https://reviews.llvm.org/D69790
* [clang,MveEmitter] Fix sign/zero extension in range limits.Simon Tatham2019-11-061-7/+6
| | | | | | | | | | | | | | | | | | | | | | | | In the code that generates Sema range checks on constant arguments, I had a piece of code that checks the bounds specified in the Tablegen intrinsic description against the range of the integer type being tested. If the bounds are large enough to permit any value of the integer type, you can omit the compile-time range check. (This case is expected to come up in some of the bitwise operation intrinsics.) But somehow I got my signed/unsigned check backwards (asking for the signed min/max of an unsigned type and vice versa), and also made a sign extension error in which a signed negative value gets zero-extended. Now rewritten more sensibly, and it should get its first sensible test from the next batch of intrinsics I'm planning to add in D69791. Reviewers: dmgreen Subscribers: cfe-commits Tags: #clang Differential Revision: https://reviews.llvm.org/D69789
* Fix MSVC "not all control paths return a value" warnings. NFCI.Simon Pilgrim2019-10-241-0/+2
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* [ARM] Attempt to fixup MveEmitter warningsDavid Green2019-10-241-5/+1
| | | | Change-Id: I3fb06de2202c3b7a9ce511a40e758d0971ef9fdb
* [clang,ARM] Initial ACLE intrinsics for MVE.Simon Tatham2019-10-241-0/+1692
This commit sets up the infrastructure for auto-generating <arm_mve.h> and doing clang-side code generation for the builtins it relies on, and demonstrates that it works by implementing a representative sample of the ACLE intrinsics, more or less matching the ones introduced in LLVM IR by D67158,D68699,D68700. Like NEON, that header file will provide a set of vector types like uint16x8_t and C functions with names like vaddq_u32(). Unlike NEON, the ACLE spec for <arm_mve.h> includes a polymorphism system, so that you can write plain vaddq() and disambiguate by the vector types you pass to it. Unlike the corresponding NEON code, I've arranged to make every user- facing ACLE intrinsic into a clang builtin, and implement all the code generation inside clang. So <arm_mve.h> itself contains nothing but typedefs and function declarations, with the latter all using the new `__attribute__((__clang_builtin))` system to arrange that the user- facing function names correspond to the right internal BuiltinIDs. So the new MveEmitter tablegen system specifies the full sequence of IRBuilder operations that each user-facing ACLE intrinsic should translate into. Where possible, the ACLE intrinsics map to standard IR operations such as vector-typed `add` and `fadd`; where no standard representation exists, I call down to the sample IR intrinsics introduced in an earlier commit. Doing it like this means that you get the polymorphism for free just by using __attribute__((overloadable)): the clang overload resolution decides which function declaration is the relevant one, and _then_ its BuiltinID is looked up, so by the time we're doing code generation, that's all been resolved by the standard system. It also means that you get really nice error messages if the user passes the wrong combination of types: clang will show the declarations from the header file and explain why each one doesn't match. (The obvious alternative approach would be to have wrapper functions in <arm_mve.h> which pass their arguments to the underlying builtins. But that doesn't work in the case where one of the arguments has to be a constant integer: the wrapper function can't pass the constantness through. So you'd have to do that case using a macro instead, and then use C11 `_Generic` to handle the polymorphism. Then you have to add horrible workarounds because `_Generic` requires even the untaken branches to type-check successfully, and //then// if the user gets the types wrong, the error message is totally unreadable!) Reviewers: dmgreen, miyuki, ostannard Subscribers: mgorny, javed.absar, kristof.beyls, cfe-commits Tags: #clang Differential Revision: https://reviews.llvm.org/D67161
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