improve description of param/ret attrs

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57061 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2008-10-04 18:33:34 +00:00
parent 88d4b597ba
commit 66d922c909

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@ -826,7 +826,8 @@ a power of 2.</p>
<div class="doc_code">
<pre>
declare i32 @printf(i8* noalias , ...)
declare i32 @atoi(i8 zeroext*)
declare i32 @atoi(i8 zeroext)
declare signext i8 @returns_signed_char()
</pre>
</div>
@ -836,19 +837,21 @@ declare i32 @atoi(i8 zeroext*)
<p>Currently, only the following parameter attributes are defined:</p>
<dl>
<dt><tt>zeroext</tt></dt>
<dd>This indicates that the parameter should be zero extended just before
a call to this function.</dd>
<dd>This indicates to the code generator that the parameter or return value
should be zero-extended to a 32-bit value by the caller (for a parameter)
or the callee (for a return value).</dd>
<dt><tt>signext</tt></dt>
<dd>This indicates that the parameter should be sign extended just before
a call to this function.</dd>
<dd>This indicates to the code generator that the parameter or return value
should be sign-extended to a 32-bit value by the caller (for a parameter)
or the callee (for a return value).</dd>
<dt><tt>inreg</tt></dt>
<dd>This indicates that this parameter or return value should be treated
in a special target-dependent fashion during while emitting code for a
function call or return (usually, by putting it in a register as opposed
to memory; in some places it is used to distinguish between two different
kinds of registers). Use of this attribute is target-specific</dd>
to memory, though some targets use it to distinguish between two different
kinds of registers). Use of this attribute is target-specific.</dd>
<dt><tt>byval</tt></dt>
<dd>This indicates that the pointer parameter should really be passed by
@ -856,13 +859,14 @@ declare i32 @atoi(i8 zeroext*)
pointee is made between the caller and the callee, so the callee is unable
to modify the value in the callee. This attribute is only valid on LLVM
pointer arguments. It is generally used to pass structs and arrays by
value, but is also valid on scalars (even though this is silly).</dd>
value, but is also valid on pointers to scalars.</dd>
<dt><tt>sret</tt></dt>
<dd>This indicates that the pointer parameter specifies the address of a
structure that is the return value of the function in the source program.
Loads and stores to the structure are assumed not to trap.
May only be applied to the first parameter.</dd>
This pointer must be guaranteed by the caller to be valid: loads and stores
to the structure may be assumed by the callee to not to trap. This may only
be applied to the first parameter.</dd>
<dt><tt>noalias</tt></dt>
<dd>This indicates that the parameter does not alias any global or any other