From 17cba8793e759bd8b4a96bb1dc5b3fd51b7cde65 Mon Sep 17 00:00:00 2001 From: Quentin Carbonneaux Date: Tue, 18 Aug 2015 17:19:08 -0400 Subject: [PATCH] add comment about variadic functions in abi --- lisc/ABI | 3 +++ 1 file changed, 3 insertions(+) diff --git a/lisc/ABI b/lisc/ABI index 735b631..d7088d4 100644 --- a/lisc/ABI +++ b/lisc/ABI @@ -36,6 +36,9 @@ Passing: on the stack. - When all registers are taken, write arguments on the stack from right to left. + - When calling a variadic function, %al stores the number + of vector registers used to pass arguments (it must be + an upper bound and does not have to be exact). - Registers %rbx, %r12 - %r15 are callee-save. Returning.