shithub: mc

Info  •  Files  •  Log  •  Branches

A bit more commenting.

--- a/6/ra.c

+++ b/6/ra.c

@@ -12,15 +12,16 @@

 #define Sizetbits (CHAR_BIT*sizeof(size_t)) /* used in graph reprs */

-typedef struct Usage Usage;

-struct Usage {

-    int l[Maxarg + 1];

-    int r[Maxarg + 1];

+typedef struct Usemap Usemap;

+struct Usemap {

+    int l[Maxarg + 1]; /* location of arg used in instruction's arg list */

+    int r[Maxarg + 1]; /* list of registers used implicitly by instruction */

 };

 static void printedge(FILE *fd, char *msg, size_t a, size_t b);

-Usage usetab[] = {

+/* tables of uses/defs by instruction */

+Usemap usetab[] = {

 #define Use(...) {__VA_ARGS__}

 #define Insn(i, fmt, use, def) use,

 #include "insns.def"

@@ -28,7 +29,7 @@

 #undef Use

 };

-Usage deftab[] = {

+Usemap deftab[] = {

 #define Def(...) {__VA_ARGS__}

 #define Insn(i, fmt, use, def) def,

 #include "insns.def"

@@ -36,6 +37,7 @@

 #undef Def

 };

+/* A map of which registers interfere */

 Reg regmap[][Nmode] = {

     [0]  = {Rnone, Ral, Rax, Reax, Rrax},

     [1]  = {Rnone, Rcl, Rcx, Recx, Rrcx},

@@ -53,6 +55,7 @@

     [13]  = {Rnone, R15b, R15w, R15d, R15},

 };

+/* Which regmap entry a register maps to */

 int colourmap[Nreg] = {

     /* byte */

     [Ral] = 0,