From 89e120ba3436f3916822dc09d32001fd53beff14 Mon Sep 17 00:00:00 2001
From: Bill Currie <bill@taniwha.org>
Date: Mon, 17 Jan 2022 16:54:27 +0900
Subject: [PATCH] [gamecode] Make return support 32 words

This took interpreting the lower 5 bits of operand c as size - 1, and
0xffff as void (0 words).
---
 libs/gamecode/pr_exec.c           | 6 +++---
 libs/gamecode/test/test-callret.c | 8 ++++----
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/libs/gamecode/pr_exec.c b/libs/gamecode/pr_exec.c
index 46d474a7b..90296c153 100644
--- a/libs/gamecode/pr_exec.c
+++ b/libs/gamecode/pr_exec.c
@@ -3131,9 +3131,9 @@ pr_exec_ruamoko (progs_t *pr, int exitdepth)
 				break;
 			OP_cmp_T (LT, U, long, lvec2, lvec4, <, ulong, ulvec2, ulvec4);
 			case OP_RETURN:
-				int         ret_size = st->c & 0x1f;	// up to 32 words
-				if (ret_size) {
-					mm = pr_return_mode (pr, st, (st->c >> 5) & 7);
+				int         ret_size = (st->c & 0x1f) + 1;	// up to 32 words
+				if (st->c != 0xffff) {
+					mm = pr_return_mode (pr, st, st->c >> 5);
 					memcpy (&R_INT (pr), mm, ret_size * sizeof (*op_a));
 				}
 				pr->pr_xfunction->profile += profile - startprofile;
diff --git a/libs/gamecode/test/test-callret.c b/libs/gamecode/test/test-callret.c
index 64a597ce7..9bf96fa54 100644
--- a/libs/gamecode/test/test-callret.c
+++ b/libs/gamecode/test/test-callret.c
@@ -85,7 +85,7 @@ static dstatement_t callret_statements[] = {
 	{ OP(2, 2, 2, OP_ADD_F_4),   fa, fi, fa },		// f += inc
 	{ OP(2, 0, 2, OP_LEA_C),      c, -1,  c },		// dec count
 	{ OP(0, 0, 2, OP_IFA),       -7,  0,  c },		// count > 0
-	{ OP(2, 0, 0, OP_RETURN),    ac,  0,  4 },
+	{ OP(2, 0, 0, OP_RETURN),    ac,  0,  3 },		// size is (c&31)+1
 #undef x
 #undef xn
 #undef x2
@@ -132,7 +132,7 @@ static dstatement_t call32_statements[] = {
     { OP(2, 0, 2, OP_LEA_C),     32, -1,   32 },
 	{ OP(2, 2, 2, OP_STORE_D_1), 33, 32,   32 },	// array[index] = index
 	{ OP(0, 0, 0, OP_JUMP_A),    -3,  0,    0 },
-	{ OP(2, 0, 0, OP_RETURN),     0,  0,   32 },
+	{ OP(2, 0, 0, OP_RETURN),     0,  0, 0x1f },	// only bits 0-5 are size
 };
 
 static pr_ivec4_t callchain_init[32] = {
@@ -152,12 +152,12 @@ static dstatement_t callchain_statements[] = {
 	{ OP_LEA_C,   STK, -4, STK },			// reserve 4 words on the stack
 	{ OP_WITH,      2,  0,   2 },			// put locals into reg 2
 	{ OP(0, 0, 2, OP_CALL_B), 2, 0, 0 },
-	{ OP(2, 0, 0, OP_RETURN), 0, 0, 1 },
+	{ OP(2, 0, 0, OP_RETURN), 0, 0, 0 },
 [64]=
 	{ OP_LEA_C,   STK, -4, STK },			// reserve 4 words on the stack
 	{ OP_WITH,      2,  0,   2 },			// put locals into reg 2
 	{ OP(0, 0, 2, OP_LEA_A),  42, 0, 0 },	// init value
-	{ OP(2, 0, 0, OP_RETURN),  0, 0, 1 },	// return value
+	{ OP(2, 0, 0, OP_RETURN),  0, 0, 0 },	// return value
 };
 
 static bfunction_t callret_functions[] = {