diff doc/manual/callconvs/callconv_arm32.tex @ 50:9bd3c5219505

- minor test code fix - doc - cleanups
author cslag
date Sun, 20 Dec 2015 15:38:14 +0100
parents c4de113dc1e9
children 9e9d6a90492a
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line diff
--- a/doc/manual/callconvs/callconv_arm32.tex	Sun Dec 20 00:12:06 2015 +0100
+++ b/doc/manual/callconvs/callconv_arm32.tex	Sun Dec 20 15:38:14 2015 +0100
@@ -338,7 +338,8 @@
 \item first 16 single-precision, or 8 double-precision arguments are passed via s0-s15 or d0-d7, respectively (note that since s and d registers are aliased, already used ones are skipped)
 \item subsequent parameters are pushed onto the stack (in right to left order, such that the stack pointer points to the first of the remaining parameters)
 \item note that as soon one floating point parameter is passed via the stack, subsequent single precision floating point parameters are also pushed onto the stack even if there are still free S* registers
-\item if the callee takes the address of one of the parameters and uses it to address other parameters (e.g. varargs) it has to copy - in its prolog - the first four words to a reserved stack area adjacent to the other parameters on the stack @@@?check spilling of float args, also
+\item floating point vararg parameters (only doubles, b/c of promotion) are pushed onth the stack, never passed via registers
+\item if the callee takes the address of one of the parameters and uses it to address other parameters (e.g. varargs) it has to copy - in its prolog - the first four words (for first 4 integer arguments) to a reserved stack area adjacent to the other parameters on the stack
 \item parameters \textless=\ 32 bits are passed as 32 bit words
 \item structures and unions are passed by value, with the first four words of the parameters in r0-r3 @@@?check doc
 \item if return value is a structure, a pointer pointing to the return value's space is passed in r0, the first parameter in r1, etc. (see {\bf return values})