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-rw-r--r--src/corelib/tools/qsimd.cpp306
1 files changed, 200 insertions, 106 deletions
diff --git a/src/corelib/tools/qsimd.cpp b/src/corelib/tools/qsimd.cpp
index 8005d7d..7babf3a 100644
--- a/src/corelib/tools/qsimd.cpp
+++ b/src/corelib/tools/qsimd.cpp
@@ -41,6 +41,7 @@
#include "qsimd_p.h"
#include <QByteArray>
+#include <stdio.h>
#if defined(Q_OS_WINCE)
#include <windows.h>
@@ -50,15 +51,32 @@
#include <intrin.h>
#endif
+#if defined(Q_OS_LINUX) && defined(__arm__)
+#include "private/qcore_unix_p.h"
+
+// the kernel header definitions for HWCAP_*
+// (the ones we need/may need anyway)
+
+// copied from <asm/hwcap.h> (ARM)
+#define HWCAP_IWMMXT 512
+#define HWCAP_CRUNCH 1024
+#define HWCAP_THUMBEE 2048
+#define HWCAP_NEON 4096
+#define HWCAP_VFPv3 8192
+#define HWCAP_VFPv3D16 16384
+
+// copied from <linux/auxvec.h>
+#define AT_HWCAP 16 /* arch dependent hints at CPU capabilities */
+
+#endif
+
QT_BEGIN_NAMESPACE
-uint qDetectCPUFeatures()
+#if defined (Q_OS_WINCE)
+static inline uint detectProcessorFeatures()
{
- static uint features = 0xffffffff;
- if (features != 0xffffffff)
- return features;
+ uint features = 0;
-#if defined (Q_OS_WINCE)
#if defined (ARM)
if (IsProcessorFeaturePresent(PF_ARM_INTEL_WMMX)) {
features = IWMMXT;
@@ -78,77 +96,98 @@ uint qDetectCPUFeatures()
#endif
features = 0;
return features;
-#elif defined(QT_HAVE_IWMMXT)
+}
+
+#elif defined(__arm__) || defined(__arm) || defined(QT_HAVE_IWMMXT) || defined(QT_HAVE_NEON)
+static inline uint detectProcessorFeatures()
+{
+ uint features = 0;
+
+#if defined(Q_OS_LINUX)
+ int auxv = ::qt_safe_open("/proc/self/auxv", O_RDONLY);
+ if (auxv != -1) {
+ unsigned long vector[64];
+ int nread;
+ while (features == 0) {
+ nread = ::qt_safe_read(auxv, (char *)vector, sizeof vector);
+ if (nread <= 0) {
+ // EOF or error
+ break;
+ }
+
+ int max = nread / (sizeof vector[0]);
+ for (int i = 0; i < max; i += 2)
+ if (vector[i] == AT_HWCAP) {
+ if (vector[i+1] & HWCAP_IWMMXT)
+ features |= IWMMXT;
+ if (vector[i+1] & HWCAP_NEON)
+ features |= NEON;
+ break;
+ }
+ }
+
+ ::qt_safe_close(auxv);
+ return features;
+ }
+ // fall back if /proc/self/auxv wasn't found
+#endif
+
+#if defined(QT_HAVE_IWMMXT)
// runtime detection only available when running as a previlegied process
- static const bool doIWMMXT = !qgetenv("QT_NO_IWMMXT").toInt();
- features = doIWMMXT ? IWMMXT : 0;
- return features;
+ features = IWMMXT;
#elif defined(QT_HAVE_NEON)
- static const bool doNEON = !qgetenv("QT_NO_NEON").toInt();
- features = doNEON ? NEON : 0;
+ features = NEON;
+#endif
+
return features;
-#else
- features = 0;
-#if defined(__x86_64__) || defined(Q_OS_WIN64)
- features = MMX|SSE|SSE2|CMOV;
-#elif defined(__ia64__)
- features = MMX|SSE|SSE2;
+}
+
#elif defined(__i386__) || defined(_M_IX86)
+static inline uint detectProcessorFeatures()
+{
+ uint features = 0;
+
unsigned int extended_result = 0;
unsigned int feature_result = 0;
uint result = 0;
/* see p. 118 of amd64 instruction set manual Vol3 */
#if defined(Q_CC_GNU)
- asm ("push %%ebx\n"
- "pushf\n"
- "pop %%eax\n"
- "mov %%eax, %%ebx\n"
- "xor $0x00200000, %%eax\n"
- "push %%eax\n"
+ long cpuid_supported, tmp1;
+ asm ("pushf\n"
+ "pop %0\n"
+ "mov %0, %1\n"
+ "xor $0x00200000, %0\n"
+ "push %0\n"
"popf\n"
"pushf\n"
- "pop %%eax\n"
- "xor %%edx, %%edx\n"
- "xor %%ebx, %%eax\n"
- "jz 1f\n"
-
- "mov $0x00000001, %%eax\n"
- "cpuid\n"
- "1:\n"
- "pop %%ebx\n"
- "mov %%edx, %0\n"
- "mov %%ecx, %1\n"
- : "=r" (result), "=r" (feature_result)
- :
- : "%eax", "%ecx", "%edx"
- );
+ "pop %0\n"
+ "xor %1, %0\n" // %eax is now 0 if CPUID is not supported
+ : "=a" (cpuid_supported), "=r" (tmp1)
+ );
+ if (cpuid_supported) {
+ asm ("xchg %%ebx, %2\n"
+ "cpuid\n"
+ "xchg %%ebx, %2\n"
+ : "=c" (feature_result), "=d" (result), "=&r" (tmp1)
+ : "a" (1));
- asm ("push %%ebx\n"
- "pushf\n"
- "pop %%eax\n"
- "mov %%eax, %%ebx\n"
- "xor $0x00200000, %%eax\n"
- "push %%eax\n"
- "popf\n"
- "pushf\n"
- "pop %%eax\n"
- "xor %%edx, %%edx\n"
- "xor %%ebx, %%eax\n"
- "jz 2f\n"
+ asm ("xchg %%ebx, %1\n"
+ "cpuid\n"
+ "cmp $0x80000000, %%eax\n"
+ "jnbe 1f\n"
+ "xor %0, %0\n"
+ "jmp 2f\n"
+ "1:\n"
+ "mov $0x80000001, %%eax\n"
+ "cpuid\n"
+ "2:\n"
+ "xchg %%ebx, %1\n"
+ : "=d" (extended_result), "=&r" (tmp1)
+ : "a" (0x80000000)
+ : "%ecx"
+ );
+ }
- "mov $0x80000000, %%eax\n"
- "cpuid\n"
- "cmp $0x80000000, %%eax\n"
- "jbe 2f\n"
- "mov $0x80000001, %%eax\n"
- "cpuid\n"
- "2:\n"
- "pop %%ebx\n"
- "mov %%edx, %0\n"
- : "=r" (extended_result)
- :
- : "%eax", "%ecx", "%edx"
- );
#elif defined (Q_OS_WIN)
_asm {
push eax
@@ -210,6 +249,7 @@ uint qDetectCPUFeatures()
}
#endif
+
// result now contains the standard feature bits
if (result & (1u << 15))
features |= CMOV;
@@ -236,33 +276,23 @@ uint qDetectCPUFeatures()
if (feature_result & (1u << 28))
features |= AVX;
-#endif // i386
+ return features;
+}
-#if defined(__x86_64__) || defined(Q_OS_WIN64)
+#elif defined(__x86_64) || defined(Q_OS_WIN64)
+static inline uint detectProcessorFeatures()
+{
+ uint features = MMX|SSE|SSE2|CMOV;
uint feature_result = 0;
#if defined(Q_CC_GNU)
- asm ("push %%rbx\n"
- "pushf\n"
- "pop %%rax\n"
- "mov %%eax, %%ebx\n"
- "xor $0x00200000, %%eax\n"
- "push %%rax\n"
- "popf\n"
- "pushf\n"
- "pop %%rax\n"
- "xor %%edx, %%edx\n"
- "xor %%ebx, %%eax\n"
- "jz 1f\n"
-
- "mov $0x00000001, %%eax\n"
+ long tmp;
+ asm ("xchg %%rbx, %1\n"
"cpuid\n"
- "1:\n"
- "pop %%rbx\n"
- "mov %%ecx, %0\n"
- : "=r" (feature_result)
- :
- : "%eax", "%ecx", "%edx"
+ "xchg %%rbx, %1\n"
+ : "=c" (feature_result), "=&r" (tmp)
+ : "a" (1)
+ : "%edx"
);
#elif defined (Q_OS_WIN64)
{
@@ -282,33 +312,97 @@ uint qDetectCPUFeatures()
features |= SSE4_2;
if (feature_result & (1u << 28))
features |= AVX;
-#endif // x86_64
-#if defined(QT_HAVE_MMX)
- if (qgetenv("QT_NO_MMX").toInt())
- features ^= MMX;
-#endif
- if (qgetenv("QT_NO_MMXEXT").toInt())
- features ^= MMXEXT;
+ return features;
+}
-#if defined(QT_HAVE_3DNOW)
- if (qgetenv("QT_NO_3DNOW").toInt())
- features ^= MMX3DNOW;
-#endif
- if (qgetenv("QT_NO_3DNOWEXT").toInt())
- features ^= MMX3DNOWEXT;
+#elif defined(__ia64__)
+static inline uint detectProcessorFeatures()
+{
+ return MMX|SSE|SSE2;
+}
-#if defined(QT_HAVE_SSE)
- if (qgetenv("QT_NO_SSE").toInt())
- features ^= SSE;
-#endif
-#if defined(QT_HAVE_SSE2)
- if (qgetenv("QT_NO_SSE2").toInt())
- features ^= SSE2;
+#else
+static inline uint detectProcessorFeatures()
+{
+ return 0;
+}
#endif
+/*
+ * Use kdesdk/scripts/generate_string_table.pl to update the table below.
+ * Here's the data (don't forget the ONE leading space):
+ mmx
+ mmxext
+ mmx3dnow
+ mmx3dnowext
+ sse
+ sse2
+ cmov
+ iwmmxt
+ neon
+ sse3
+ ssse3
+ sse4.1
+ sse4.2
+ avx
+ */
+
+// begin generated
+static const char features_string[] =
+ " mmx\0"
+ " mmxext\0"
+ " mmx3dnow\0"
+ " mmx3dnowext\0"
+ " sse\0"
+ " sse2\0"
+ " cmov\0"
+ " iwmmxt\0"
+ " neon\0"
+ " sse3\0"
+ " ssse3\0"
+ " sse4.1\0"
+ " sse4.2\0"
+ " avx\0"
+ "\0";
+
+static const int features_indices[] = {
+ 0, 5, 13, 23, 36, 41, 47, 53,
+ 61, 67, 73, 80, 88, 96, -1
+};
+// end generated
+
+const int features_count = (sizeof features_indices - 1) / (sizeof features_indices[0]);
+
+uint qDetectCPUFeatures()
+{
+ static QBasicAtomicInt features = Q_BASIC_ATOMIC_INITIALIZER(-1);
+ if (features != -1)
+ return features;
+
+ uint f = detectProcessorFeatures();
+ QByteArray disable = qgetenv("QT_NO_CPU_FEATURE");
+ if (!disable.isEmpty()) {
+ disable.prepend(' ');
+ for (int i = 0; i < features_count; ++i) {
+ if (disable.contains(features_string + features_indices[i]))
+ f &= ~(1 << i);
+ }
+ }
+
+ features = f;
return features;
-#endif
+}
+
+void qDumpCPUFeatures()
+{
+ uint features = qDetectCPUFeatures();
+ printf("Processor features: ");
+ for (int i = 0; i < features_count; ++i) {
+ if (features & (1 << i))
+ printf("%s", features_string + features_indices[i]);
+ }
+ puts("");
}
QT_END_NAMESPACE
generated by cgit v0.12 at 2024-11-13 13:14:30 (GMT)