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@@ -158,22 +158,25 @@ const
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+ PIC support
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* return +Inf/0 for +Inf/-Inf input, instead of NaN }
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function fpc_exp_real(d : ValReal) : ValReal;assembler;compilerproc;
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+ const
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+ ln2hi: double=6.9314718036912382E-001;
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+ ln2lo: double=1.9082149292705877E-010;
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+ large: single=24576.0;
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+ two: single=2.0;
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+ half: single=0.5;
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asm
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+ call .LPIC
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+.LPIC:
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+ pop %ecx
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fldt d
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fldl2e
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fmul %st(1),%st { z = d * log2(e) }
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frndint
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- { Calculate frac(z) using modular arithmetic to avoid precision loss.
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- Avoid PIC hacks by using immediate operands (it's not the fastest,
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- but likely the cleanest solution). }
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- pushl $0x3fe62e42 { ln(2).hi=6.9314718036912382E-001 }
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- pushl $0xfee00000
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- fldl (%esp)
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+ { Calculate frac(z) using modular arithmetic to avoid precision loss. }
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+ fldl ln2hi-.LPIC(%ecx)
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fmul %st(1),%st
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fsubrp %st,%st(2)
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- pushl $0x3dea39ef { ln(2).lo=1.9082149292705877E-010 }
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- pushl $0x35793c76
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- fldl (%esp)
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+ fldl ln2lo-.LPIC(%ecx)
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fmul %st(1),%st
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fsubrp %st,%st(2)
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fxch %st(1) { (d-int(z)*ln2_hi)-int(z)*ln2_lo }
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@@ -193,8 +196,7 @@ const
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jae .L1 { frac(z) <= 1 }
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fld %st(1)
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fabs
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- pushl $0x46c00000 { single(24576.0) }
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- fcomps (%esp)
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+ fcomps large-.LPIC(%ecx)
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fstsw %ax
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sahf
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jb .L0 { int(z) < 24576 }
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@@ -204,12 +206,10 @@ const
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jmp .L1
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.L0:
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{ Calculate 2**frac(z)-1 as N*(N+2), where N=2**(frac(z)/2)-1 }
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- pushl $0x3f000000 { single(0.5) }
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- fmuls (%esp)
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+ fmuls half-.LPIC(%ecx)
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f2xm1
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fld %st
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- pushl $0x40000000 { single(2.0) }
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- fadds (%esp)
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+ fadds two-.LPIC(%ecx)
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fmulp %st,%st(1)
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jmp .L2
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.L1:
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sergei