fpcraxp.asm

来自「开放源码的编译器open watcom 1.6.0版的源代码」· 汇编 代码 · 共 58 行

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    .text

    .globl  _GetFPCR            // Get current contents of the FPCR
    .globl  _SetFPCR            // Set contents of the FPCR

_GetFPCR:
    lda     $sp,-0x10($sp)      // Make some room on the stack
    excb                        // Make sure all instructions have completed
    mf_fpcr $f0                 // Load the FPCR contents into F0
    excb                        // Wait until we've completed
    stt     $f0, ($sp)          // Write them out to the stack
    ldl     $v0, 0x04($sp)          // Load the high dword into V0 (all we need)
    lda     $sp, 0x10($sp)      // Restore the stack
    ret                         // Return

_SetFPCR:
    lda     $sp,-0x10($sp)      // Make some room on the stack
    stq     $zero, ($sp)
    stl     $a0, 0x04($sp)      // Write A0 to the stack
    ldt     $f0, ($sp)          // Load into F0 (note only high dword matters)
    lda     $sp, 0x10($sp)      // Restore the stack
    excb                        // Make sure all instructions have completed
    mt_fpcr $f0                 // Write F0 out to the FPCR
    excb                        // Wait until we've completed
    ret                         // Return