Add unordered branches for NaN cases to amd64 comparison trampolines.

diff --git a/src/microcode/cmpauxmd/x86-64.m4 b/src/microcode/cmpauxmd/x86-64.m4
index d48935bea4aae5fc430966f6b347b056ea7d35a1..c1b3aaf21358eb4743e161ebb5530e848e910559 100644 (file)
--- a/src/microcode/cmpauxmd/x86-64.m4
+++ b/src/microcode/cmpauxmd/x86-64.m4
@@ -783,6 +783,10 @@ asm_generic_$1_flo:
        OP(and,q)       TW(rmask,REG(rbx))
        movsd           TW(QOF(FLONUM_DATA_OFFSET,REG(rdx)),REG(xmm0))
        ucomisd         TW(QOF(FLONUM_DATA_OFFSET,REG(rbx)),REG(xmm0))
+       # ucomisd sets the parity bit if the operands are incomparable,
+       # i.e. either one is NaN; in that case, return #F.  Otherwise,
+       # return #T if $4 is met, or #F otherwise.
+       jp      asm_generic_return_sharp_f
        $4      asm_generic_return_sharp_t
        jmp     asm_generic_return_sharp_f
 
@@ -852,9 +856,11 @@ asm_generic_divide_fix_by_flo:
 
 asm_generic_divide_zero_by_flo:
        # rcx contains zero, representing a numerator exactly zero.
-       # Defer division of 0 by 0.0; otherwise, yield exactly zero.
+       # Defer division of 0 by 0.0 or NaN; otherwise, yield exactly
+       # zero.
        OP(cvtsi2sd,q)  TW(REG(rcx),REG(xmm0))
        ucomisd         TW(REG(xmm1),REG(xmm0))
+       jp      asm_generic_divide_fail
        je      asm_generic_divide_fail
        OP(and,q)       TW(rmask,IND(REG(rsp)))
        OP(mov,q)       TW(IMM_FIXNUM_0,REG(rax))
@@ -870,6 +876,7 @@ asm_generic_divide_flo_by_flo:
        movsd           TW(QOF(FLONUM_DATA_OFFSET,REG(rax)),REG(xmm0))
        movsd           TW(QOF(FLONUM_DATA_OFFSET,REG(rcx)),REG(xmm1))
        ucomisd         TW(ABS(EVR(flonum_zero)),REG(xmm1))
+       jp      asm_generic_divide_fail
        je      asm_generic_divide_fail
        divsd           TW(REG(xmm1),REG(xmm0))
        jmp     asm_generic_flonum_result