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Made to work with troff

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ceriel
1990-06-20 10:05:22 +00:00
parent 97e131bc81
commit 39730420a2
25 changed files with 583 additions and 456 deletions
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doc/ego/cs/cs4
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@@ -26,26 +26,26 @@ There are groups for all sorts of operators:
unary, binary, and ternary.
The groups of operators are further partitioned according to the size
of their operand(s) and result.
\" .PP
\" The distinction between operators and expensive loads is not always clear.
\" The ADP instruction for example,
\" might seem a unary operator because it pops one item
\" (a pointer) from the stack.
\" However, two ADP-instructions which pop an item with the same value number
\" need not have the same result,
\" because the attributes (an offset, to be added to the pointer)
\" can be different.
\" Is it then a binary operator?
\" That would give rise to the strange, and undesirable,
\" situation that some binary operators pop two operands
\" and others pop one.
\" The conclusion is inevitable:
\" we have been fooled by the name (ADd Pointer).
\" The ADP-instruction is an expensive load.
\" In this context LAF, meaning Load Address of oFfsetted,
\" would have been a better name,
\" corresponding to LOF, like LAL,
\" Load Address of Local, corresponds to LOL.
.\" .PP
.\" The distinction between operators and expensive loads is not always clear.
.\" The ADP instruction for example,
.\" might seem a unary operator because it pops one item
.\" (a pointer) from the stack.
.\" However, two ADP-instructions which pop an item with the same value number
.\" need not have the same result,
.\" because the attributes (an offset, to be added to the pointer)
.\" can be different.
.\" Is it then a binary operator?
.\" That would give rise to the strange, and undesirable,
.\" situation that some binary operators pop two operands
.\" and others pop one.
.\" The conclusion is inevitable:
.\" we have been fooled by the name (ADd Pointer).
.\" The ADP-instruction is an expensive load.
.\" In this context LAF, meaning Load Address of oFfsetted,
.\" would have been a better name,
.\" corresponding to LOF, like LAL,
.\" Load Address of Local, corresponds to LOL.
.PP
There are groups for all sorts of stores:
direct, indirect, array element.
@@ -91,10 +91,13 @@ because EM expressions are postfix.
When we find an instruction to load an operand,
we load on the fake-stack a struct with the following information:
.DS
(1) the value number of the operand
(2) the size of the operand
(3) a pointer to the first line of EM-code
that constitutes the operand
.TS
l l.
(1) the value number of the operand
(2) the size of the operand
(3) a pointer to the first line of EM-code
that constitutes the operand
.TE
.DE
In most cases, (3) will point to the line
that loaded the operand (e.g. LOL, LOC),
@@ -121,9 +124,12 @@ a recurrence of this expression.
Not only will the operand(s) be popped from the fake-stack,
but the following will be pushed:
.DS
(1) the value number of the result
(2) the size of the result
(3) a pointer to the first line of the expression
.TS
l l.
(1) the value number of the result
(2) the size of the result
(3) a pointer to the first line of the expression
.TE
.DE
In this way an item on the fake-stack always contains
the necessary information.