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https://git.eden-emu.dev/eden-emu/eden
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fix ffs
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parent
c394cc704e
commit
212eb4ced3
1 changed files with 16 additions and 3 deletions
19
externals/bc_decoder/bc_decoder.cpp
vendored
19
externals/bc_decoder/bc_decoder.cpp
vendored
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@ -8,10 +8,9 @@
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#include <array>
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#include <array>
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#include <assert.h>
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#include <assert.h>
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#include <bit>
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#include <stddef.h>
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#include <stddef.h>
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#include <stdint.h>
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#include <stdint.h>
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#include <strings.h>
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#include <bit>
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namespace {
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namespace {
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constexpr int32_t BlockWidth = 4;
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constexpr int32_t BlockWidth = 4;
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@ -1040,7 +1039,21 @@ namespace {
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/**/ {0x6, 0x1, 0x0, 0x0, 0x0, 0x7, 0x7, 0x1, 0x0, 0x4, 0x3f, 0x0},
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/**/ {0x6, 0x1, 0x0, 0x0, 0x0, 0x7, 0x7, 0x1, 0x0, 0x4, 0x3f, 0x0},
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/**/ {0x7, 0x2, 0x6, 0x0, 0x0, 0x5, 0x5, 0x1, 0x0, 0x2, 0x1e, 0x0},
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/**/ {0x7, 0x2, 0x6, 0x0, 0x0, 0x5, 0x5, 0x1, 0x0, 0x2, 0x1e, 0x0},
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};
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};
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return m_table[::ffs(low & 0b11111111)];
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// Fun historical fact: this is basically ffs(), however, windows does NOT have ffs()
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// This is because ffs() comes from VAX which had an instruction for ffs(), but
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// to the surprise of absolutely nobody, VAX ended up dying, alongside ffs()... or so
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// I tought. It turns out only *NIX world kept ffs() while windows, not bound by POSIX
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// standards, just dropped it altogether. Even through Windows had a VAX port at once time
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// there isn't much one can do other than scream.
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if ((low & 0b00000001) != 0) return m_table[0];
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else if ((low & 0b00000010) != 0) return m_table[1];
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else if ((low & 0b00000100) != 0) return m_table[2];
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else if ((low & 0b00001000) != 0) return m_table[3];
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else if ((low & 0b00010000) != 0) return m_table[4];
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else if ((low & 0b00100000) != 0) return m_table[5];
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else if ((low & 0b01000000) != 0) return m_table[6];
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else if ((low & 0b10000000) != 0) return m_table[7];
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return m_table[0]; //invalid but pretend it's fine
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}
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}
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struct IndexInfo {
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struct IndexInfo {
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