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diff --git a/mdk-stage1/dietlibc/i386/cosh.S b/mdk-stage1/dietlibc/i386/cosh.S
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+
+.text
+.type cosh,@function
+.global cosh
+
+cosh: # note: exp(x) = 2^(x*log2(e))
+ fldl2e
+ fmull 4(%esp) # x*log2(e)
+ fld %st(0) # x*log2(e) x*log2(e)
+ frndint # int(x*log2(e)) x*log2(e)
+ fxch # x*log2(e) int(x*log2(e))
+ fsub %st(1),%st(0) # frac(x*log2(e)) int(x*log2(e))
+ f2xm1 # 2^(fract(x*log2(e)))-1 int(x*log2(e))
+ fld1 # 1 2^(fract(x*log2(e)))-1 int(x*log2(e))
+ faddp %st(0),%st(1) # 2^(fract(x*log2(e))) int(x*log2(e))
+ fscale # 2^(x*log2(e)) int(x*log2(e))
+ fstp %st(1) # 2^(x*log2(e))
+
+# now we have y = exp(x), but cosh(x) = (y + 1/y) * 0.5
+
+ fld1
+ fdiv %st(1),%st(0)
+ faddp
+ fmuls __half
+ ret
+
+.Lende:
+
+.size cosh,.ende-cosh