(temp-offset-low (* (1+ stack-offset) sb!vm:n-word-bytes)))
(inst lis rtemp #x4330) ; High word of magic constant
(inst stw rtemp nfp-tn temp-offset-high)
- (inst lis rtemp #x-8000)
+ (inst lis rtemp #x8000)
(inst stw rtemp nfp-tn temp-offset-low)
(inst lfd fmagic nfp-tn temp-offset-high)
(inst xor rtemp rtemp x) ; invert sign bit of x : rtemp had #x80000000