GCC behaviour difference (-mgpopt)

[mkst]

This scratch shows different GCC behaviour between the PSYQ binary and our compiled one.

Other than the code difference, our version spits out the variables at the end of the file, rather than the start, which is caused by this diff (i.e. we want TARGET_FILE_SWITCHING to be true):

dezgeg commented:

aha, they have done some ugly hack:

--- gcc-2.8.1/config/mips/mips.h        1997-12-29 02:34:57.000000000 +0200
+++ GCC281S/config/mips/mips.h  2025-03-31 23:08:43.433889661 +0300
@@ -367,7 +367,11 @@
 /* This is true if we must enable the assembly language file switching
    code.  */

+/* GIL : This is an unpleasant way of enabling target file switching. */
+/*
 #define TARGET_FILE_SWITCHING  (TARGET_GP_OPT && ! TARGET_GAS)
+*/
+#define TARGET_FILE_SWITCHING   (TARGET_GP_OPT && TARGET_GAS)

 /* We must disable the function end stabs when doing the file switching trick,
    because the Lscope stabs end up in the wrong place, making it impossible
@@ -1255,7 +1259,12 @@
 #define POINTER_BOUNDARY (TARGET_LONG64 ? 64 : 32)

 /* Allocation boundary (in *bits*) for storing arguments in argument list.  */
+/* GIL - Grim hack for N64 with -mgp64 - experimental for Richard Frankish */
+/* DAVE - this code was already in here.  why is limiting Allocation Boundary to 32 bits grim?
+/*
 #define PARM_BOUNDARY (TARGET_64BIT ? 64 : 32)
+*/
+#define PARM_BOUNDARY 32

 /* Allocation boundary (in *bits*) for the code of a function.  */
 #define FUNCTION_BOUNDARY 32