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[Xen-devel] [PATCH v4 08/17] x86emul: test coverage for SSE/SSE2 insns

To: "xen-devel" <xen-devel@xxxxxxxxxxxxxxxxxxxx>

From: "Jan Beulich" <JBeulich@xxxxxxxx>

Date: Tue, 28 Feb 2017 05:53:57 -0700

Cc: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>

Delivery-date: Tue, 28 Feb 2017 12:54:13 +0000

List-id: Xen developer discussion <xen-devel.lists.xen.org>

... and their AVX equivalents. Note that a few instructions aren't covered (yet), but those all fall into common pattern groups, so I would hope that for now we can do with what is there. MMX insns aren't being covered at all, as they're not easy to deal with: The compiler refuses to emit such for other than uses of built-in functions. The current way of testing AVX insns is meant to be temporary only: Once we fully support that feature, the present tests should rather be replaced than full ones simply added. Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx> Acked-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx> --- v4: Put spaces around ##. Parenthesize uses of macro parameters. Fix indentation for a few preprocessor directives. v2: New. --- a/tools/tests/x86_emulator/Makefile +++ b/tools/tests/x86_emulator/Makefile @@ -11,11 +11,36 @@ all: $(TARGET) run: $(TARGET) ./$(TARGET) -TESTCASES := blowfish +TESTCASES := blowfish simd blowfish-cflags := "" blowfish-cflags-x86_32 := "-mno-accumulate-outgoing-args -Dstatic=" +sse-vecs := 16 +sse-ints := +sse-flts := 4 +sse2-vecs := $(sse-vecs) +sse2-ints := 1 2 4 8 +sse2-flts := 4 8 + +# When converting SSE to AVX, have the compiler avoid XMM0 to widen +# coverage of the VEX.vvvv checks in the emulator. +sse2avx := -ffixed-xmm0 -Wa,-msse2avx + +simd-cflags := $(foreach flavor,sse sse2, \ + $(foreach vec,$($(flavor)-vecs), \ + $(foreach int,$($(flavor)-ints), \ + "-D$(flavor)_$(vec)i$(int) -m$(flavor) -O2 -DVEC_SIZE=$(vec) -DINT_SIZE=$(int)" \ + "-D$(flavor)_$(vec)u$(int) -m$(flavor) -O2 -DVEC_SIZE=$(vec) -DUINT_SIZE=$(int)" \ + "-D$(flavor)_avx_$(vec)i$(int) -m$(flavor) $(sse2avx) -O2 -DVEC_SIZE=$(vec) -DINT_SIZE=$(int)" \ + "-D$(flavor)_avx_$(vec)u$(int) -m$(flavor) $(sse2avx) -O2 -DVEC_SIZE=$(vec) -DUINT_SIZE=$(int)") \ + $(foreach flt,$($(flavor)-flts), \ + "-D$(flavor)_$(vec)f$(flt) -m$(flavor) -O2 -DVEC_SIZE=$(vec) -DFLOAT_SIZE=$(flt)" \ + "-D$(flavor)_avx_$(vec)f$(flt) -m$(flavor) $(sse2avx) -O2 -DVEC_SIZE=$(vec) -DFLOAT_SIZE=$(flt)")) \ + $(foreach flt,$($(flavor)-flts), \ + "-D$(flavor)_f$(flt) -m$(flavor) -mfpmath=sse -O2 -DFLOAT_SIZE=$(flt)" \ + "-D$(flavor)_avx_f$(flt) -m$(flavor) -mfpmath=sse $(sse2avx) -O2 -DFLOAT_SIZE=$(flt)")) + $(addsuffix .h,$(TESTCASES)): %.h: %.c testcase.mk Makefile rm -f $@.new $*.bin $(foreach arch,$(filter-out $(XEN_COMPILE_ARCH),x86_32) $(XEN_COMPILE_ARCH), \ --- /dev/null +++ b/tools/tests/x86_emulator/simd.c @@ -0,0 +1,450 @@ +#include <stdbool.h> + +asm ( + "\t.text\n" + "\t.globl _start\n" + "_start:\n" +#if defined(__i386__) && VEC_SIZE == 16 + "\tpush %ebp\n" + "\tmov %esp,%ebp\n" + "\tand $~0xf,%esp\n" + "\tcall simd_test\n" + "\tleave\n" + "\tret" +#else + "\tjmp simd_test" +#endif + ); + +typedef +#if defined(INT_SIZE) +# define ELEM_SIZE INT_SIZE +signed int +# if INT_SIZE == 1 +# define MODE QI +# elif INT_SIZE == 2 +# define MODE HI +# elif INT_SIZE == 4 +# define MODE SI +# elif INT_SIZE == 8 +# define MODE DI +# endif +#elif defined(UINT_SIZE) +# define ELEM_SIZE UINT_SIZE +unsigned int +# if UINT_SIZE == 1 +# define MODE QI +# elif UINT_SIZE == 2 +# define MODE HI +# elif UINT_SIZE == 4 +# define MODE SI +# elif UINT_SIZE == 8 +# define MODE DI +# endif +#elif defined(FLOAT_SIZE) +float +# define ELEM_SIZE FLOAT_SIZE +# if FLOAT_SIZE == 4 +# define MODE SF +# elif FLOAT_SIZE == 8 +# define MODE DF +# endif +#endif +#ifndef VEC_SIZE +# define VEC_SIZE ELEM_SIZE +#endif +__attribute__((mode(MODE), vector_size(VEC_SIZE))) vec_t; + +#define ELEM_COUNT (VEC_SIZE / ELEM_SIZE) + +typedef unsigned int __attribute__((mode(QI), vector_size(VEC_SIZE))) byte_vec_t; + +/* Various builtins want plain char / int / long long vector types ... */ +typedef char __attribute__((vector_size(VEC_SIZE))) vqi_t; +typedef short __attribute__((vector_size(VEC_SIZE))) vhi_t; +typedef int __attribute__((vector_size(VEC_SIZE))) vsi_t; +#if VEC_SIZE >= 8 +typedef long long __attribute__((vector_size(VEC_SIZE))) vdi_t; +#endif + +#if VEC_SIZE == 8 && defined(__SSE__) +# define to_bool(cmp) (__builtin_ia32_pmovmskb(cmp) == 0xff) +#elif VEC_SIZE == 16 +# if defined(__SSE__) && ELEM_SIZE == 4 +# define to_bool(cmp) (__builtin_ia32_movmskps(cmp) == 0xf) +# elif defined(__SSE2__) +# if ELEM_SIZE == 8 +# define to_bool(cmp) (__builtin_ia32_movmskpd(cmp) == 3) +# else +# define to_bool(cmp) (__builtin_ia32_pmovmskb128(cmp) == 0xffff) +# endif +# endif +#endif + +#ifndef to_bool +static inline bool _to_bool(byte_vec_t bv) +{ + unsigned int i; + + for ( i = 0; i < VEC_SIZE; ++i ) + if ( bv[i] != 0xff ) + return false; + + return true; +} +# define to_bool(cmp) _to_bool((byte_vec_t)(cmp)) +#endif + +#if VEC_SIZE == FLOAT_SIZE +# define to_int(x) ((vec_t){ (int)(x)[0] }) +#elif VEC_SIZE == 16 && defined(__SSE2__) +# if FLOAT_SIZE == 4 +# define to_int(x) __builtin_ia32_cvtdq2ps(__builtin_ia32_cvtps2dq(x)) +# elif FLOAT_SIZE == 8 +# define to_int(x) __builtin_ia32_cvtdq2pd(__builtin_ia32_cvtpd2dq(x)) +# endif +#endif + +#if VEC_SIZE == FLOAT_SIZE +# define scalar_1op(x, op) ({ \ + typeof((x)[0]) __attribute__((vector_size(16))) r_; \ + asm ( op : [out] "=&x" (r_) : [in] "m" (x) ); \ + (vec_t){ r_[0] }; \ +}) +#endif + +#if FLOAT_SIZE == 4 && defined(__SSE__) +# if VEC_SIZE == 16 +# define interleave_hi(x, y) __builtin_ia32_unpckhps(x, y) +# define interleave_lo(x, y) __builtin_ia32_unpcklps(x, y) +# define max(x, y) __builtin_ia32_maxps(x, y) +# define min(x, y) __builtin_ia32_minps(x, y) +# define recip(x) __builtin_ia32_rcpps(x) +# define rsqrt(x) __builtin_ia32_rsqrtps(x) +# define sqrt(x) __builtin_ia32_sqrtps(x) +# define swap(x) __builtin_ia32_shufps(x, x, 0b00011011) +# elif VEC_SIZE == 4 +# define recip(x) scalar_1op(x, "rcpss %[in], %[out]") +# define rsqrt(x) scalar_1op(x, "rsqrtss %[in], %[out]") +# define sqrt(x) scalar_1op(x, "sqrtss %[in], %[out]") +# endif +#elif FLOAT_SIZE == 8 && defined(__SSE2__) +# if VEC_SIZE == 16 +# define interleave_hi(x, y) __builtin_ia32_unpckhpd(x, y) +# define interleave_lo(x, y) __builtin_ia32_unpcklpd(x, y) +# define max(x, y) __builtin_ia32_maxpd(x, y) +# define min(x, y) __builtin_ia32_minpd(x, y) +# define recip(x) __builtin_ia32_cvtps2pd(__builtin_ia32_rcpps(__builtin_ia32_cvtpd2ps(x))) +# define rsqrt(x) __builtin_ia32_cvtps2pd(__builtin_ia32_rsqrtps(__builtin_ia32_cvtpd2ps(x))) +# define sqrt(x) __builtin_ia32_sqrtpd(x) +# define swap(x) __builtin_ia32_shufpd(x, x, 0b01) +# elif VEC_SIZE == 8 +# define recip(x) scalar_1op(x, "cvtsd2ss %[in], %[out]; rcpss %[out], %[out]; cvtss2sd %[out], %[out]") +# define rsqrt(x) scalar_1op(x, "cvtsd2ss %[in], %[out]; rsqrtss %[out], %[out]; cvtss2sd %[out], %[out]") +# define sqrt(x) scalar_1op(x, "sqrtsd %[in], %[out]") +# endif +#endif +#if VEC_SIZE == 16 && defined(__SSE2__) +# if INT_SIZE == 1 || UINT_SIZE == 1 +# define interleave_hi(x, y) ((vec_t)__builtin_ia32_punpckhbw128((vqi_t)(x), (vqi_t)(y))) +# define interleave_lo(x, y) ((vec_t)__builtin_ia32_punpcklbw128((vqi_t)(x), (vqi_t)(y))) +# elif INT_SIZE == 2 || UINT_SIZE == 2 +# define interleave_hi(x, y) ((vec_t)__builtin_ia32_punpckhwd128((vhi_t)(x), (vhi_t)(y))) +# define interleave_lo(x, y) ((vec_t)__builtin_ia32_punpcklwd128((vhi_t)(x), (vhi_t)(y))) +# define swap(x) ((vec_t)__builtin_ia32_pshufd( \ + (vsi_t)__builtin_ia32_pshufhw( \ + __builtin_ia32_pshuflw((vhi_t)(x), 0b00011011), 0b00011011), 0b01001110)) +# elif INT_SIZE == 4 || UINT_SIZE == 4 +# define interleave_hi(x, y) ((vec_t)__builtin_ia32_punpckhdq128((vsi_t)(x), (vsi_t)(y))) +# define interleave_lo(x, y) ((vec_t)__builtin_ia32_punpckldq128((vsi_t)(x), (vsi_t)(y))) +# define swap(x) ((vec_t)__builtin_ia32_pshufd((vsi_t)(x), 0b00011011)) +# elif INT_SIZE == 8 || UINT_SIZE == 8 +# define interleave_hi(x, y) ((vec_t)__builtin_ia32_punpckhqdq128((vdi_t)(x), (vdi_t)(y))) +# define interleave_lo(x, y) ((vec_t)__builtin_ia32_punpcklqdq128((vdi_t)(x), (vdi_t)(y))) +# define swap(x) ((vec_t)__builtin_ia32_pshufd((vsi_t)(x), 0b01001110)) +# endif +# if UINT_SIZE == 1 +# define max(x, y) ((vec_t)__builtin_ia32_pmaxub128((vqi_t)(x), (vqi_t)(y))) +# define min(x, y) ((vec_t)__builtin_ia32_pminub128((vqi_t)(x), (vqi_t)(y))) +# elif INT_SIZE == 2 +# define max(x, y) __builtin_ia32_pmaxsw128(x, y) +# define min(x, y) __builtin_ia32_pminsw128(x, y) +# define mul_hi(x, y) __builtin_ia32_pmulhw128(x, y) +# elif UINT_SIZE == 2 +# define mul_hi(x, y) ((vec_t)__builtin_ia32_pmulhuw128((vhi_t)(x), (vhi_t)(y))) +# elif UINT_SIZE == 4 +# define mul_full(x, y) ((vec_t)__builtin_ia32_pmuludq128((vsi_t)(x), (vsi_t)(y))) +# endif +# define select(d, x, y, m) ({ \ + void *d_ = (d); \ + vqi_t m_ = (vqi_t)(m); \ + __builtin_ia32_maskmovdqu((vqi_t)(x), m_, d_); \ + __builtin_ia32_maskmovdqu((vqi_t)(y), ~m_, d_); \ +}) +#endif +#if VEC_SIZE == FLOAT_SIZE +# define max(x, y) ((vec_t){({ typeof(x[0]) x_ = (x)[0], y_ = (y)[0]; x_ > y_ ? x_ : y_; })}) +# define min(x, y) ((vec_t){({ typeof(x[0]) x_ = (x)[0], y_ = (y)[0]; x_ < y_ ? x_ : y_; })}) +#endif + +/* + * Suppress value propagation by the compiler, preventing unwanted + * optimization. This at once makes the compiler use memory operands + * more often, which for our purposes is the more interesting case. + */ +#define touch(var) asm volatile ( "" : "+m" (var) ) + +int simd_test(void) +{ + unsigned int i, j; + vec_t x, y, z, src, inv, alt, sh; + + for ( i = 0, j = ELEM_SIZE << 3; i < ELEM_COUNT; ++i ) + { + src[i] = i + 1; + inv[i] = ELEM_COUNT - i; +#ifdef UINT_SIZE + alt[i] = -!(i & 1); +#else + alt[i] = i & 1 ? -1 : 1; +#endif + if ( !(i & (i + 1)) ) + --j; + sh[i] = j; + } + + touch(src); + x = src; + touch(x); + if ( !to_bool(x == src) ) return __LINE__; + + touch(src); + y = x + src; + touch(src); + touch(y); + if ( !to_bool(y == 2 * src) ) return __LINE__; + + touch(src); + z = y -= src; + touch(z); + if ( !to_bool(x == z) ) return __LINE__; + +#if defined(UINT_SIZE) + + touch(inv); + x |= inv; + touch(inv); + y &= inv; + touch(inv); + z ^= inv; + touch(inv); + touch(x); + if ( !to_bool((x & ~y) == z) ) return __LINE__; + +#elif ELEM_SIZE > 1 || VEC_SIZE <= 8 + + touch(src); + x *= src; + y = inv * inv; + touch(src); + z = src + inv; + touch(inv); + z *= (src - inv); + if ( !to_bool(x - y == z) ) return __LINE__; + +#endif + +#if defined(FLOAT_SIZE) + + x = src * alt; + touch(alt); + y = src / alt; + if ( !to_bool(x == y) ) return __LINE__; + touch(alt); + touch(src); + if ( !to_bool(x * -alt == -src) ) return __LINE__; + +# if defined(recip) && defined(to_int) + + touch(src); + x = recip(src); + touch(src); + touch(x); + if ( !to_bool(to_int(recip(x)) == src) ) return __LINE__; + +# ifdef rsqrt + x = src * src; + touch(x); + y = rsqrt(x); + touch(y); + if ( !to_bool(to_int(recip(y)) == src) ) return __LINE__; + touch(src); + if ( !to_bool(to_int(y) == to_int(recip(src))) ) return __LINE__; +# endif + +# endif + +# ifdef sqrt + x = src * src; + touch(x); + if ( !to_bool(sqrt(x) == src) ) return __LINE__; +# endif + +#else + +# if ELEM_SIZE > 1 + + touch(inv); + x = src * inv; + touch(inv); + y[ELEM_COUNT - 1] = y[0] = j = ELEM_COUNT; + for ( i = 1; i < ELEM_COUNT / 2; ++i ) + y[ELEM_COUNT - i - 1] = y[i] = y[i - 1] + (j -= 2); + if ( !to_bool(x == y) ) return __LINE__; + +# ifdef mul_hi + touch(alt); + x = mul_hi(src, alt); + touch(alt); +# ifdef INT_SIZE + if ( !to_bool(x == (alt < 0)) ) return __LINE__; +# else + if ( !to_bool(x == (src & alt) + alt) ) return __LINE__; +# endif +# endif + +# ifdef mul_full + x = src ^ alt; + touch(inv); + y = mul_full(x, inv); + touch(inv); + for ( i = 0; i < ELEM_COUNT; i += 2 ) + { + unsigned long long res = x[i] * 1ULL * inv[i]; + + z[i] = res; + z[i + 1] = res >> (ELEM_SIZE << 3); + } + if ( !to_bool(y == z) ) return __LINE__; +# endif + + z = src; +# ifdef INT_SIZE + z *= alt; +# endif + touch(z); + x = z << 3; + touch(z); + y = z << 2; + touch(z); + if ( !to_bool(x == y + y) ) return __LINE__; + + touch(x); + z = x >> 2; + touch(x); + if ( !to_bool(y == z + z) ) return __LINE__; + + z = src; +# ifdef INT_SIZE + z *= alt; +# endif + /* + * Note that despite the touch()-es here there doesn't appear to be a way + * to make the compiler use a memory operand for the shift instruction (at + * least without resorting to built-ins). + */ + j = 3; + touch(j); + x = z << j; + touch(j); + j = 2; + touch(j); + y = z << j; + touch(j); + if ( !to_bool(x == y + y) ) return __LINE__; + + z = x >> j; + touch(j); + if ( !to_bool(y == z + z) ) return __LINE__; + +# endif + +# if ELEM_SIZE == 2 || defined(__SSE4_1__) + /* + * Even when there are no instructions with varying shift counts per + * field, the code turns out to be a nice exercise for pextr/pinsr. + */ + z = src; +# ifdef INT_SIZE + z *= alt; +# endif + /* + * Zap elements for which the shift count is negative (and the hence the + * decrement below would yield a negative count. + */ + z &= (sh > 0); + touch(sh); + x = z << sh; + touch(sh); + --sh; + touch(sh); + y = z << sh; + touch(sh); + if ( !to_bool(x == y + y) ) return __LINE__; + +# endif + +#endif + +#if defined(max) && defined(min) +# ifdef UINT_SIZE + touch(inv); + x = min(src, inv); + touch(inv); + y = max(src, inv); + touch(inv); + if ( !to_bool(x + y == src + inv) ) return __LINE__; +# else + x = src * alt; + y = inv * alt; + touch(y); + z = max(x, y); + touch(y); + y = min(x, y); + touch(y); + if ( !to_bool((y + z) * alt == src + inv) ) return __LINE__; +# endif +#endif + +#ifdef swap + touch(src); + if ( !to_bool(swap(src) == inv) ) return __LINE__; +#endif + +#if defined(interleave_lo) && defined(interleave_hi) + touch(src); + x = interleave_lo(inv, src); + touch(src); + y = interleave_hi(inv, src); + touch(src); +# ifdef UINT_SIZE + z = ((x - y) ^ ~alt) - ~alt; +# else + z = (x - y) * alt; +# endif + if ( !to_bool(z == ELEM_COUNT / 2) ) return __LINE__; +#endif + +#ifdef select +# ifdef UINT_SIZE + select(&z, src, inv, alt); +# else + select(&z, src, inv, alt > 0); +# endif + for ( i = 0; i < ELEM_COUNT; ++i ) + y[i] = (i & 1 ? inv : src)[i]; + if ( !to_bool(z == y) ) return __LINE__; +#endif + + return 0; +} --- a/tools/tests/x86_emulator/test_x86_emulator.c +++ b/tools/tests/x86_emulator/test_x86_emulator.c @@ -5,6 +5,7 @@ #include "x86_emulate.h" #include "blowfish.h" +#include "simd.h" #define verbose false /* Switch to true for far more logging. */ @@ -19,11 +20,43 @@ static bool blowfish_check_regs(const st return regs->eax == 2 && regs->edx == 1; } +static bool simd_check_sse(void) +{ + return cpu_has_sse; +} + +static bool simd_check_sse2(void) +{ + return cpu_has_sse2; +} + +static bool simd_check_avx(void) +{ + return cpu_has_avx; +} +#define simd_check_sse_avx simd_check_avx +#define simd_check_sse2_avx simd_check_avx + +static void simd_set_regs(struct cpu_user_regs *regs) +{ + if ( cpu_has_mmx ) + asm volatile ( "emms" ); +} + +static bool simd_check_regs(const struct cpu_user_regs *regs) +{ + if ( !regs->eax ) + return true; + printf("[line %u] ", (unsigned int)regs->eax); + return false; +} + static const struct { const void *code; size_t size; unsigned int bitness; const char*name; + bool (*check_cpu)(void); void (*set_regs)(struct cpu_user_regs *); bool (*check_regs)(const struct cpu_user_regs *); } blobs[] = { @@ -39,6 +72,49 @@ static const struct { BLOWFISH(32, blowfish, ), BLOWFISH(32, blowfish (push), _mno_accumulate_outgoing_args), #undef BLOWFISH +#define SIMD_(bits, desc, feat, form) \ + { .code = simd_x86_ ## bits ## _D ## feat ## _ ## form, \ + .size = sizeof(simd_x86_ ## bits ## _D ## feat ## _ ## form), \ + .bitness = bits, .name = #desc, \ + .check_cpu = simd_check_ ## feat, \ + .set_regs = simd_set_regs, \ + .check_regs = simd_check_regs } +#ifdef __x86_64__ +# define SIMD(desc, feat, form) SIMD_(64, desc, feat, form), \ + SIMD_(32, desc, feat, form) +#else +# define SIMD(desc, feat, form) SIMD_(32, desc, feat, form) +#endif + SIMD(SSE scalar single, sse, f4), + SIMD(SSE packed single, sse, 16f4), + SIMD(SSE2 scalar single, sse2, f4), + SIMD(SSE2 packed single, sse2, 16f4), + SIMD(SSE2 scalar double, sse2, f8), + SIMD(SSE2 packed double, sse2, 16f8), + SIMD(SSE2 packed s8, sse2, 16i1), + SIMD(SSE2 packed u8, sse2, 16u1), + SIMD(SSE2 packed s16, sse2, 16i2), + SIMD(SSE2 packed u16, sse2, 16u2), + SIMD(SSE2 packed s32, sse2, 16i4), + SIMD(SSE2 packed u32, sse2, 16u4), + SIMD(SSE2 packed s64, sse2, 16i8), + SIMD(SSE2 packed u64, sse2, 16u8), + SIMD(SSE/AVX scalar single, sse_avx, f4), + SIMD(SSE/AVX packed single, sse_avx, 16f4), + SIMD(SSE2/AVX scalar single, sse2_avx, f4), + SIMD(SSE2/AVX packed single, sse2_avx, 16f4), + SIMD(SSE2/AVX scalar double, sse2_avx, f8), + SIMD(SSE2/AVX packed double, sse2_avx, 16f8), + SIMD(SSE2/AVX packed s8, sse2_avx, 16i1), + SIMD(SSE2/AVX packed u8, sse2_avx, 16u1), + SIMD(SSE2/AVX packed s16, sse2_avx, 16i2), + SIMD(SSE2/AVX packed u16, sse2_avx, 16u2), + SIMD(SSE2/AVX packed s32, sse2_avx, 16i4), + SIMD(SSE2/AVX packed u32, sse2_avx, 16u4), + SIMD(SSE2/AVX packed s64, sse2_avx, 16i8), + SIMD(SSE2/AVX packed u64, sse2_avx, 16u8), +#undef SIMD_ +#undef SIMD }; static unsigned int bytes_read; @@ -2589,6 +2665,9 @@ int main(int argc, char **argv) continue; } + if ( blobs[j].check_cpu && !blobs[j].check_cpu() ) + continue; + memcpy(res, blobs[j].code, blobs[j].size); ctxt.addr_size = ctxt.sp_size = blobs[j].bitness;

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