Push one of seven commonly used constants (in double extended-precision floating-point format) onto the FPU register stack. The constants that can be loaded with these instructions include +1.0, +0.0, log_10(2), log_e(2), pi, log_2(10), and log_2(e). For each constant, an internal 66-bit constant is rounded (as specified by the RC field in the FPU control word) to double extendedprecision floating-point format. The inexact-result exception (#P) is not generated as a result of the rounding, nor is the C1 flag set in the x87 FPU status word if the value is rounded up.
See the section titled "Pi" in Chapter 8 of the IA-32 Intel Architecture Software Developer's Manual, Volume 1, for a description of the pi constant.