From 1ac09dc704d199bb680b9b5939907ec828b5a61e Mon Sep 17 00:00:00 2001
From: Michael Forney <mforney@mforney.org>
Date: Tue, 19 Oct 2021 13:41:29 -0700
Subject: Use disp8 when possible for memarg.

---
 main.c       | 12 +++++-------
 test/test.sh |  1 +
 2 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/main.c b/main.c
index ce1caa0..8f17d17 100644
--- a/main.c
+++ b/main.c
@@ -395,14 +395,12 @@ assemblemem(const Memarg* memarg, Rex rex, VarBytes prefix, VarBytes opcode,
     /* Case when we don't need sib */
     if (memarg->index == ASM_NO_REG && memarg->scale == 0 && ((rm & 7) != 4)) {
 
-        if (memarg->disp.l == 0 && memarg->disp.c == 0) {
-            if ((rm & 7) == 5) {
-                mod = 1;
-            } else {
-                mod = 0;
-            }
-        } else {
+        if (memarg->disp.l != NULL || memarg->disp.c > INT8_MAX || memarg->disp.c < INT8_MIN) {
             mod = 2;
+        } else if (memarg->disp.c != 0 || (rm & 7) == 5) {
+            mod = 1;
+        } else {
+            mod = 0;
         }
 
         assemblevbytes(prefix);
diff --git a/test/test.sh b/test/test.sh
index 152ea2b..ecf5ce1 100644
--- a/test/test.sh
+++ b/test/test.sh
@@ -43,6 +43,7 @@ t "callq *%rax"
 t "callq *%r10"
 t "callq *(%r10)"
 t "movb %r11b, (%rsi, %r12, 1)"
+t "mov %rdi, -0x60(%rbp)"
 
 for r in rax r10
 do
-- 
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