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Merge pull request #3086 from kinke/stdarg_aarch64
[stable] core.{stdc.stdarg,vararg}: Add support for non-Apple AArch64
2 parents 3961b6e + 3da2ace commit 15955a1

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6 files changed

+217
-18
lines changed

6 files changed

+217
-18
lines changed

‎mak/COPY

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@@ -55,6 +55,7 @@ COPY=\
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\
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$(IMPDIR)\core\internal\util\array.d \
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\
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$(IMPDIR)\core\internal\vararg\aarch64.d \
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$(IMPDIR)\core\internal\vararg\sysv_x64.d \
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\
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$(IMPDIR)\core\stdc\assert_.d \

‎mak/SRCS

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\
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src\core\internal\util\array.d \
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\
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src\core\internal\vararg\aarch64.d \
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src\core\internal\vararg\sysv_x64.d \
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\
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src\core\stdc\assert_.d \

‎src/core/internal/vararg/aarch64.d

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/**
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* Varargs implementation for the AArch64 Procedure Call Standard (not followed by Apple).
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* Used by core.stdc.stdarg and core.vararg.
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*
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* Reference: https://github.com/ARM-software/abi-aa/blob/master/aapcs64/aapcs64.rst#appendix-variable-argument-lists
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*
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* Copyright: Copyright Digital Mars 2020 - 2020.
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* License: $(HTTP www.boost.org/LICENSE_1_0.txt, Boost License 1.0).
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* Authors: Martin Kinkelin
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* Source: $(DRUNTIMESRC core/internal/vararg/aarch64.d)
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*/
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module core.internal.vararg.aarch64;
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version (AArch64):
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// Darwin uses a simpler varargs implementation
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version (OSX) {}
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else version (iOS) {}
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else version (TVOS) {}
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else version (WatchOS) {}
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else:
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import core.stdc.stdarg : alignUp;
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@system:
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//@nogc: // Not yet, need to make TypeInfo's member functions @nogc first
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nothrow:
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extern (C++, std) struct __va_list
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{
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void* __stack;
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void* __gr_top;
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void* __vr_top;
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int __gr_offs;
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int __vr_offs;
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}
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///
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alias va_list = __va_list;
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///
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T va_arg(T)(ref va_list ap)
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{
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static if (is(T ArgTypes == __argTypes))
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{
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T onStack()
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{
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void* arg = ap.__stack;
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static if (T.alignof > 8)
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arg = arg.alignUp!16;
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ap.__stack = alignUp(arg + T.sizeof);
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version (BigEndian)
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static if (T.sizeof < 8)
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arg += 8 - T.sizeof;
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return *cast(T*) arg;
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}
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static if (ArgTypes.length == 0)
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{
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// indirectly by value; get pointer and copy
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T* ptr = va_arg!(T*)(ap);
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return *ptr;
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}
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static assert(ArgTypes.length == 1);
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static if (is(ArgTypes[0] E : E[N], int N))
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alias FundamentalType = E; // static array element type
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else
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alias FundamentalType = ArgTypes[0];
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static if (__traits(isFloating, FundamentalType) || isVectorType!FundamentalType)
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{
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import core.stdc.string : memcpy;
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// SIMD register(s)
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int offs = ap.__vr_offs;
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if (offs >= 0)
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return onStack(); // reg save area empty
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enum int usedRegSize = FundamentalType.sizeof;
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static assert(T.sizeof % usedRegSize == 0);
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enum int nreg = T.sizeof / usedRegSize;
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ap.__vr_offs = offs + (nreg * 16);
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if (ap.__vr_offs > 0)
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return onStack(); // overflowed reg save area
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version (BigEndian)
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static if (usedRegSize < 16)
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offs += 16 - usedRegSize;
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T result = void;
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static foreach (i; 0 .. nreg)
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memcpy((cast(void*) &result) + i * usedRegSize, ap.__vr_top + (offs + i * 16), usedRegSize);
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return result;
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}
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else
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{
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// GP register(s)
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int offs = ap.__gr_offs;
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if (offs >= 0)
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return onStack(); // reg save area empty
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static if (T.alignof > 8)
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offs = offs.alignUp!16;
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enum int nreg = (T.sizeof + 7) / 8;
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ap.__gr_offs = offs + (nreg * 8);
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if (ap.__gr_offs > 0)
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return onStack(); // overflowed reg save area
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version (BigEndian)
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static if (T.sizeof < 8)
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offs += 8 - T.sizeof;
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return *cast(T*) (ap.__gr_top + offs);
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}
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}
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else
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{
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static assert(false, "not a valid argument type for va_arg");
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}
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}
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///
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void va_arg()(ref va_list ap, TypeInfo ti, void* parmn)
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{
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import core.stdc.string : memcpy;
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const size = ti.tsize;
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const alignment = ti.talign;
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if (auto ti_struct = cast(TypeInfo_Struct) ti)
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{
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TypeInfo arg1, arg2;
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ti.argTypes(arg1, arg2);
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if (!arg1)
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{
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// indirectly by value; get pointer and move
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void* ptr = va_arg!(void*)(ap);
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memcpy(parmn, ptr, size);
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return;
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}
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assert(!arg2);
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ti = arg1;
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}
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void onStack()
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{
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void* arg = ap.__stack;
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if (alignment > 8)
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arg = arg.alignUp!16;
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ap.__stack = alignUp(arg + size);
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version (BigEndian)
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if (size < 8)
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arg += 8 - size;
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memcpy(parmn, arg, size);
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}
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// HFVA structs have already been lowered to static arrays;
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// lower `ti` further to the fundamental type, including HFVA
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// static arrays.
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// TODO: complex numbers
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if (auto ti_sarray = cast(TypeInfo_StaticArray) ti)
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ti = ti_sarray.value;
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if (ti.flags() & 2)
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{
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// SIMD register(s)
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int offs = ap.__vr_offs;
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if (offs >= 0)
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return onStack(); // reg save area empty
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const usedRegSize = cast(int) ti.tsize;
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assert(size % usedRegSize == 0);
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const nreg = cast(int) (size / usedRegSize);
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ap.__vr_offs = offs + (nreg * 16);
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if (ap.__vr_offs > 0)
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return onStack(); // overflowed reg save area
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version (BigEndian)
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if (usedRegSize < 16)
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offs += 16 - usedRegSize;
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foreach (i; 0 .. nreg)
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memcpy(parmn + i * usedRegSize, ap.__vr_top + (offs + i * 16), usedRegSize);
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return;
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}
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// GP register(s)
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int offs = ap.__gr_offs;
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if (offs >= 0)
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return onStack(); // reg save area empty
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if (alignment > 8)
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offs = offs.alignUp!16;
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const nreg = cast(int) ((size + 7) / 8);
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ap.__gr_offs = offs + (nreg * 8);
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if (ap.__gr_offs > 0)
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return onStack(); // overflowed reg save area
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version (BigEndian)
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if (size < 8)
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offs += 8 - size;
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memcpy(parmn, ap.__gr_top + offs, size);
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}

‎src/core/internal/vararg/sysv_x64.d

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/**
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* Varargs implementation for the x86_64 System V ABI (not used for Win64).
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* Used by core.stdc.stdarg.
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* Used by core.stdc.stdarg and core.vararg.
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*
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* Reference: https://www.uclibc.org/docs/psABI-x86_64.pdf
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*
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2020

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version (SysV_x64):
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import core.stdc.stdarg: alignUp;
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import core.stdc.stdarg : alignUp;
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@system:
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//@nogc: // Not yet, need to make TypeInfo's member functions @nogc first
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}
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alias __va_list = __va_list_tag;
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/*
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/**
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* Making it an array of 1 causes va_list to be passed as a pointer in
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* function argument lists
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*/

‎src/core/stdc/stdarg.d

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@@ -57,8 +57,15 @@ version (ARM_Any)
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else version (WatchOS) {}
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else:
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version (ARM) version = AAPCS32;
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version (AArch64) version = AAPCS64;
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version (ARM)
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{
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version = AAPCS32;
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}
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else version (AArch64)
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{
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version = AAPCS64;
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static import core.internal.vararg.aarch64;
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}
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}
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}
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else version (AAPCS64)
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{
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alias va_list = __va_list;
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// https://github.com/ARM-software/abi-aa/blob/master/aapcs64/aapcs64.rst#definition-of-va-list
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extern (C++, std) struct __va_list
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{
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void* __stack;
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void* __gr_top;
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void* __vr_top;
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int __gr_offs;
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int __vr_offs;
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}
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alias va_list = core.internal.vararg.aarch64.va_list;
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}
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else
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{
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}
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else version (AAPCS64)
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{
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static assert(0, "Unsupported platform");
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return core.internal.vararg.aarch64.va_arg!T(ap);
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}
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else version (ARM_Any)
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{

‎src/core/vararg.d

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@@ -104,7 +104,8 @@ void va_arg()(ref va_list ap, TypeInfo ti, void* parmn)
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}
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else version (AAPCS64)
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{
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static assert(0, "Unsupported platform");
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static import core.internal.vararg.aarch64;
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core.internal.vararg.aarch64.va_arg(ap, ti, parmn);
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}
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else version (ARM_Any)
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{

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