ARM: Add register assignments, type definitions and stack layout.

2 files changed, 70 insertions, 7 deletions

diff --git a/src/buildvm_arm.dasc b/src/buildvm_arm.dasc
index c52cfc6c..9d2efa67 100644
--- a/src/buildvm_arm.dasc
+++ b/src/buildvm_arm.dasc
@@ -15,6 +15,70 @@
 |
 |//-----------------------------------------------------------------------
 |
+|// Fixed register assignments for the interpreter.
+|
+|// The following must be C callee-save (but BASE is often refetched).
+|.define BASE,          r4      // Base of current Lua stack frame.
+|.define KBASE,         r5      // Constants of current Lua function.
+|.define PC,            r6      // Next PC.
+|.define DISPATCH,      r7      // Opcode dispatch table.
+|.define LREG,          r8      // Register holding lua_State (also in SAVE_L).
+|.define MASKR8,        r9      // 255*8 constant for fast bytecode decoding.
+|
+|// The following temporaries are not saved across C calls, except for RA/RC.
+|.define RA,            r10     // Callee-save.
+|.define RC,            r11     // Callee-save.
+|.define RB,            r12
+|.define OP,            r12     // Overlaps RB, must not be lr.
+|.define INS,           lr
+|
+|// Calling conventions. Also used as temporaries.
+|.define CARG1,         r0
+|.define CARG2,         r1
+|.define CARG3,         r2
+|.define CARG4,         r3
+|.define CARG12,        r0      // For 1st soft-fp double.
+|.define CARG34,        r2      // For 2nd soft-fp double.
+|
+|.define CRET1,         r0
+|.define CRET2,         r1
+|
+|// Stack layout while in interpreter. Must match with lj_frame.h.
+|.define CFRAME_SPACE,  #28
+|.define SAVE_ERRF,     [sp, #24]
+|.define SAVE_NRES,     [sp, #20]
+|.define SAVE_CFRAME,   [sp, #16]
+|.define SAVE_L,        [sp, #12]
+|.define SAVE_PC,       [sp, #8]
+|.define SAVE_MULTRES,  [sp, #4]
+|.define ARG5,          [sp]
+|
+|.macro saveregs
+|  push {r4, r5, r6, r7, r8, r9, r10, r11, lr}
+|  sub sp, sp, CFRAME_SPACE
+|.endmacro
+|.macro restoreregs_ret
+|  add sp, sp, CFRAME_SPACE
+|  pop {r4, r5, r6, r7, r8, r9, r10, r11, pc}
+|.endmacro
+|
+|// Type definitions. Some of these are only used for documentation.
+|.type L,               lua_State,      LREG
+|.type GL,              global_State
+|.type TVALUE,          TValue
+|.type GCOBJ,           GCobj
+|.type STR,             GCstr
+|.type TAB,             GCtab
+|.type LFUNC,           GCfuncL
+|.type CFUNC,           GCfuncC
+|.type PROTO,           GCproto
+|.type UPVAL,           GCupval
+|.type NODE,            Node
+|.type NARGS8,          int
+|.type TRACE,           GCtrace
+|
+|//-----------------------------------------------------------------------
+|
 |// Trap for not-yet-implemented parts.
 |.macro NYI; ud; .endmacro
 |
diff --git a/src/lj_frame.h b/src/lj_frame.h
index 21074724..c123353e 100644
--- a/src/lj_frame.h
+++ b/src/lj_frame.h
@@ -91,13 +91,12 @@ enum {
 #define CFRAME_SHIFT_MULTRES    0
 #endif
 #elif LJ_TARGET_ARM
-/* NYI: Dummy definitions for now. */
-#define CFRAME_OFS_ERRF         28
-#define CFRAME_OFS_NRES         24
-#define CFRAME_OFS_PREV         20
-#define CFRAME_OFS_L            16
-#define CFRAME_OFS_PC           12
-#define CFRAME_OFS_MULTRES      8
+#define CFRAME_OFS_ERRF         24
+#define CFRAME_OFS_NRES         20
+#define CFRAME_OFS_PREV         16
+#define CFRAME_OFS_L            12
+#define CFRAME_OFS_PC           8
+#define CFRAME_OFS_MULTRES      4
 #define CFRAME_SIZE             64
 #define CFRAME_SIZE_JIT         CFRAME_SIZE
 #define CFRAME_SHIFT_MULTRES    3