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Kernel: Fix Processor::features_string() stopping too early and detect more features

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The exit condition for the loop was sizeof(m_features) * 8,
which was 32. Presumably this was supposed to mean 32 bits, but it
actually made it stop as soon as it reached the 6th bit.

Also add detection for more SIMD CPU features.
This commit is contained in:
Luke 2020-08-31 14:27:38 +01:00 • committed by Andreas Kling
parent 259f8541fc
commit 8a2fd0e436
2 changed files with 35 additions and 4 deletions
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30
Kernel/Arch/i386/CPU.cpp
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@ -785,14 +785,26 @@ void Processor::cpu_detect()
m_features = static_cast<CPUFeature>(0);
CPUID processor_info(0x1);
if (processor_info.edx() & (1 << 4))
set_feature(CPUFeature::TSC);
if (processor_info.edx() & (1 << 6))
set_feature(CPUFeature::PAE);
if (processor_info.edx() & (1 << 13))
set_feature(CPUFeature::PGE);
if (processor_info.edx() & (1 << 23))
set_feature(CPUFeature::MMX);
if (processor_info.edx() & (1 << 25))
set_feature(CPUFeature::SSE);
if (processor_info.edx() & (1 << 4))
set_feature(CPUFeature::TSC);
if (processor_info.edx() & (1 << 26))
set_feature(CPUFeature::SSE2);
if (processor_info.ecx() & (1 << 0))
set_feature(CPUFeature::SSE3);
if (processor_info.ecx() & (1 << 9))
set_feature(CPUFeature::SSSE3);
if (processor_info.ecx() & (1 << 19))
set_feature(CPUFeature::SSE4_1);
if (processor_info.ecx() & (1 << 20))
set_feature(CPUFeature::SSE4_2);
if (processor_info.ecx() & (1 << 30))
set_feature(CPUFeature::RDRAND);
if (processor_info.edx() & (1 << 11)) {
@ -916,6 +928,18 @@ String Processor::features_string() const
return "sep";
case CPUFeature::SYSCALL:
return "syscall";
case CPUFeature::MMX:
return "mmx";
case CPUFeature::SSE2:
return "sse2";
case CPUFeature::SSE3:
return "sse3";
case CPUFeature::SSSE3:
return "ssse3";
case CPUFeature::SSE4_1:
return "sse4.1";
case CPUFeature::SSE4_2:
return "sse4.2";
// no default statement here intentionally so that we get
// a warning if a new feature is forgotten to be added here
}
@ -923,7 +947,7 @@ String Processor::features_string() const
return "???";
};
bool first = true;
for (u32 flag = 1; flag < sizeof(m_features) * 8; flag <<= 1) {
for (u32 flag = 1; flag != 0; flag <<= 1) {
if ((static_cast<u32>(m_features) & flag) != 0) {
if (first)
first = false;