汇编中FILD,FADD,FLD,FMUL都是有什么用?
麻烦详细说说它们的详细计算过程
[解决办法]
浮点数运算指令：
fild:m16i/m32i/m64i;取存储器的整数,压入栈顶ST(0)。
FLD:M32R/M64R/M80R/ST(I);取存储器或ST(I)中的浮点数,压入栈顶。
FADD:M32R/M64R;ST(0)--ST(0)+32R/M64R。
FADD:ST,ST(I);ST(0)--ST(0)+ST(0)。
FADD:ST(I),ST(0);ST(I)--ST(I)+ST(0)。
FADD:ST(1)--ST(1)+ST(0),并出栈。
FMUL：M32R/M64R;ST(0)--ST(0)*M32R/M64R。
FMUL:ST,ST(I);ST(0)--ST(0)*ST(I)。
FMUL:ST(I),ST--(0);ST(I)*ST(0)。
FMUL;ST(1)--ST(1)*ST(0),并出栈。
[解决办法]
参考一下浮点指令手册吧，eg:
FMUL
Title: Multiply
Syntax: FMUL [dest,src]
FMULP dest,ST
FMUL src
FIMUL src
Description:
Multiplies the source by the destination and returns the product in the destination. If two register operands are specified, one must be ST. If a memory operand is specified, the product replaces the value in ST. Memory operands can be 32- or 64-bit real numbers or 16- or 32-bit integers.
If no operand is specified, ST(1) is multiplied by ST and the stack is popped; the product is returned in ST. For FMULP, the source must be ST; the product is returned in the destination register and ST is popped.
-o-
----------------------------
FMUL [reg,reg] | fmul st,st(2) | 486 16
| fmul st(5),st |
| fmul |
----------------------------
FMULP reg,ST | fmulp st(6),st | 486 16
----------------------------
FMUL memreal | fmul DWORD PTR [bx] | 486 s=11,l=14
| fmul shortreal[di+3] |
| fmul longreal |
| |
----------------------------
FIMUL memint | fimul int16 | 486 w=23-27,d=22-24
| fimul warray[di] |
| fimul double |
| |
----------------------------
* The clocks in parentheses show times for short values--those with 40
trailing zeros in their fraction because they were loaded from a
short-real memory operand.
?The clocks in parentheses show typical speeds.
_ If the register operand is a short value--having 40 trailing zeros
in its fraction because it was loaded from a short-real memory
operand--then the timing is (112-126)+EA on the 8087 or 112-126 on
the 80287.
-o-
[解决办法]
F开头的基本上都是浮点指令，网上搜索一下可以找到详细的浮点指令集说明。
[解决办法]
you can find them at Floating Point Help (at masm32\help\fphelp.hlp),
or HLA book
[解决办法]
浮点数
[解决办法]
前面的都说完，俺混点分^_^
[解决办法]
也给我点分吧
