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* common/swap: Improve codegen of the default swap fallbacksLioncash2019-04-121-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Uses arithmetic that can be identified more trivially by compilers for optimizations. e.g. Rather than shifting the halves of the value and then swapping and combining them, we can swap them in place. e.g. for the original swap32 code on x86-64, clang 8.0 would generate: mov ecx, edi rol cx, 8 shl ecx, 16 shr edi, 16 rol di, 8 movzx eax, di or eax, ecx ret while GCC 8.3 would generate the ideal: mov eax, edi bswap eax ret now both generate the same optimal output. MSVC used to generate the following with the old code: mov eax, ecx rol cx, 8 shr eax, 16 rol ax, 8 movzx ecx, cx movzx eax, ax shl ecx, 16 or eax, ecx ret 0 Now MSVC also generates a similar, but equally optimal result as clang/GCC: bswap ecx mov eax, ecx ret 0 ==== In the swap64 case, for the original code, clang 8.0 would generate: mov eax, edi bswap eax shl rax, 32 shr rdi, 32 bswap edi or rax, rdi ret (almost there, but still missing the mark) while, again, GCC 8.3 would generate the more ideal: mov rax, rdi bswap rax ret now clang also generates the optimal sequence for this fallback as well. This is a case where MSVC unfortunately falls short, despite the new code, this one still generates a doozy of an output. mov r8, rcx mov r9, rcx mov rax, 71776119061217280 mov rdx, r8 and r9, rax and edx, 65280 mov rax, rcx shr rax, 16 or r9, rax mov rax, rcx shr r9, 16 mov rcx, 280375465082880 and rax, rcx mov rcx, 1095216660480 or r9, rax mov rax, r8 and rax, rcx shr r9, 16 or r9, rax mov rcx, r8 mov rax, r8 shr r9, 8 shl rax, 16 and ecx, 16711680 or rdx, rax mov eax, -16777216 and rax, r8 shl rdx, 16 or rdx, rcx shl rdx, 16 or rax, rdx shl rax, 8 or rax, r9 ret 0 which is pretty unfortunate.
* common/swap: Mark byte swapping free functions with [[nodiscard]] and noexceptLioncash2019-04-121-11/+11
| | | | | | | | Allows the compiler to inform when the result of a swap function is being ignored (which is 100% a bug in all usage scenarios). We also mark them noexcept to allow other functions using them to be able to be marked as noexcept and play nicely with things that potentially inspect "nothrowability".
* common/swap: Simplify swap function ifdefsLioncash2019-04-121-48/+15
| | | | | | | | | | | | | | | | | | | Including every OS' own built-in byte swapping functions is kind of undesirable, since it adds yet another build path to ensure compilation succeeds on. Given we only support clang, GCC, and MSVC for the time being, we can utilize their built-in functions directly instead of going through the OS's API functions. This shrinks the overall code down to just if (msvc) use msvc's functions else if (clang or gcc) use clang/gcc's builtins else use the slow path
* common/swap: Remove 32-bit ARM pathLioncash2019-04-121-13/+0
| | | | | We don't plan to support host 32-bit ARM execution environments, so this is essentially dead code.
* Merge pull request #2090 from FearlessTobi/port-4599bunnei2019-03-211-35/+139
|\ | | | | Port citra-emu/citra#4244 and citra-emu/citra#4599: Changes to BitField
| * common/swap: remove default value for swap type internal storageWeiyi Wang2019-02-061-1/+1
| | | | | | | | This is compromise for swap type being used in union. A union has deleted default constructor if it has at least one variant member with non-trivial default constructor, and no variant member of T has a default member initializer. In the use case of Bitfield, all variant members will be the swap type on endianness mismatch, which would all have non-trivial default constructor if default value is specified, and non of them can have member initializer
| * common/swap: use template and tag for LE/BE specificationWeiyi Wang2019-02-061-39/+91
| | | | | | | | The tag can be useful for other type-generic templates like BitFields to forward the endianness specification
| * common/swap: add swap template for enumWeiyi Wang2019-02-061-0/+52
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* | Remove GCC version checkstgsm2019-02-241-3/+3
|/ | | | Citra can't be compiled using GCC <7 because of required C++17 support, so these version checks don't need to exist anymore.
* Port #3732 from Citra: "common: Fix compilation on ARM"Cameron Cawley2018-07-291-1/+1
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* common/swap: Remove unnecessary const on return value of swap()Lioncash2018-07-191-1/+1
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* common/swap: Use static_cast where applicableLioncash2018-07-191-16/+16
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* common/swap: Use using aliases where applicableLioncash2018-07-191-33/+33
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* Port #3579 from CitrafearlessTobi2018-07-071-1/+1
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* common: fix swap functions on Bitrig and OpenBSDDaniel Lim Wee Soong2018-04-021-1/+13
| | | | | | | | | swap{16,32,64} are defined as macros on the two, but client code tries to invoke them as Common::swap{16,32,64}, which naturally doesn't work. This hack redefines the macros as inline functions in the Common namespace: the bodies of the functions are the same as the original macros, but relying on OS-specific implementation details like this is of course brittle.
* common: use system bswap* functions on more BSDsJan Beich2016-10-281-2/+5
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* Remove empty newlines in #include blocks.Emmanuel Gil Peyrot2016-09-211-2/+0
| | | | | | | This makes clang-format useful on those. Also add a bunch of forgotten transitive includes, which otherwise prevented compilation.
* Manually tweak source formatting and then re-run clang-formatYuri Kunde Schlesner2016-09-191-2/+1
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* Sources: Run clang-format on everything.Emmanuel Gil Peyrot2016-09-181-140/+191
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* swap: Get rid of pointer casting for swapping structsLioncash2016-05-091-5/+5
| | | | These shouldn't haphazardly convert types
* swap: Get rid of undefined behavior in swapf and swapdLioncash2016-05-091-14/+18
| | | | This isn't well-defined in C++.
* swap: Remove unused methodsLioncash2016-05-091-28/+0
| | | | | | | Also gets rid of pointer data variants as this prevents the use of the regular swapping routines as unary predicates in std lib functions. They also cast to stricter alignment types, which is undefined behavior.
* common: Get rid of a cast in swap.hLioncash2015-09-111-2/+2
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* Common: Cleanup memory and misc includes.Emmanuel Gil Peyrot2015-06-281-3/+7
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* Remove every trailing whitespace from the project (but externals).Emmanuel Gil Peyrot2015-05-291-1/+1
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* Removed swap code redundancy and moved common swap code to swap.harchshift2015-03-061-14/+97
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* Common: Remove dead platform #ifdefs to make the code more readable.Emmanuel Gil Peyrot2015-01-061-4/+0
| | | | | | Symbian, Xbox, Blackberry and iOS got removed. FreeBSD and Android kept due to them potentially being able to run Citra in the future. The iOS specific part also got removed from PPSSPP in order to fix a bug there.
* Fix compile errors in ClangYuri Kunde Schlesner2014-10-261-1/+0
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* fixes to build on linuxbunnei2014-04-231-13/+13
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* got rid of 'src' folders in each sub-projectbunnei2014-04-091-0/+535
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