Use ir_ctx.fixed_regset to limit available registers

Makefile

@@ -1,5 +1,5 @@
 CC         = gcc
-#CFLAGS     = -O2 -g -Wall -DIR_TARGET_X64 -DIR_DEBUG_REGSET
+#CFLAGS     = -O2 -g -Wall -DIR_TARGET_X64
 CFLAGS     = -O0 -g -Wall -DIR_DEBUG -DIR_TARGET_X64
 LDFLAGS    = -lm
 PHP        = php

ir.c

@@ -287,6 +287,7 @@ void ir_init(ir_ctx *ctx, ir_ref consts_limit, ir_ref insns_limit)
 	ctx->rules = NULL;
 	ctx->vregs_count = 0;
 	ctx->vregs = NULL;
+	ctx->fixed_regset = 0;
 	ctx->live_intervals = NULL;
 	ctx->regs = NULL;
 	ctx->prev_insn_len = NULL;

ir.h

@@ -434,6 +434,7 @@ typedef struct _ir_ctx {
 	uint32_t          *rules;
 	uint32_t           vregs_count;
 	uint32_t          *vregs;
+	uint64_t           fixed_regset;
 	ir_live_interval **live_intervals;
 	ir_regs           *regs;
 	uint32_t          *prev_insn_len;
@@ -591,15 +592,4 @@ int ir_mem_protect(void *ptr, size_t size);
 int ir_mem_unprotect(void *ptr, size_t size);
 int ir_mem_flush(void *ptr, size_t size);
 
-/* IR Debug API */
-#ifdef IR_DEBUG
-# ifndef IR_DEBUG_REGSET
-#  define IR_DEBUG_REGSET
-# endif
-#endif
-
-#ifdef IR_DEBUG_REGSET
-extern uint64_t debug_regset;
-#endif
-
 #endif /* IR_H */

ir_gcm.c

@@ -474,6 +474,7 @@ restart:
 	/* Linearization */
 	ir_init(&new_ctx, ctx->consts_count, ctx->insns_count);
 	new_ctx.flags = ctx->flags;
+	new_ctx.fixed_regset = ctx->fixed_regset;
 	/* TODO: linearize without reallocation and reconstruction ??? */
 	if (!ir_copy(&new_ctx, ctx, _next, 1)) {
 		ir_free(&new_ctx);

ir_main.c

@@ -210,6 +210,7 @@ int main(int argc, char **argv)
 	uint32_t dump = 0;
 	int opt_level = 2;
 	uint32_t mflags = 0;
+	uint64_t debug_regset = 0xffffffffffffffff;
 
 	ir_consistency_check();
 
@@ -302,7 +303,6 @@ int main(int argc, char **argv)
 		} else if (strcmp(argv[i], "--debug-ra") == 0) {
 			mflags |= IR_DEBUG_RA;
 #endif
-#ifdef IR_DEBUG_REGSET
 		} else if (strcmp(argv[i], "--debug-regset") == 0) {
 			if (i + 1 == argc || argv[i + 1][0] == '-') {
 				fprintf(stderr, "ERROR: Invalid usage' (use --help)\n");
@@ -310,7 +310,6 @@ int main(int argc, char **argv)
 			}
 			debug_regset = strtoull(argv[i + 1], NULL, 0);
 			i++;
-#endif
 		} else if (argv[i][0] == '-') {
 			fprintf(stderr, "ERROR: Unknown option '%s' (use --help)\n", argv[i]);
 			return 1;
@@ -355,6 +354,7 @@ int main(int argc, char **argv)
 	if (dump_asm || run) {
 		ctx.flags |= IR_GEN_NATIVE;
 	}
+	ctx.fixed_regset = ~debug_regset;
 
 	if (!ir_load(&ctx, f)) {
 		fprintf(stderr, "ERROR: Cannot load input file '%s'\n", input);

ir_private.h

@@ -6,9 +6,6 @@
 #ifdef IR_DEBUG
 # include <assert.h>
 # define IR_ASSERT(x) assert(x)
-# ifndef IR_DEBUG_REGSET
-#  define IR_DEBUG_REGSET
-# endif
 #else
 # define IR_ASSERT(x)
 #endif

ir_ra.c

@@ -17,10 +17,6 @@
 # pragma GCC diagnostic ignored "-Warray-bounds"
 #endif
 
-#ifdef IR_DEBUG_REGSET
-uint64_t debug_regset = 0xffffffffffffffff;
-#endif
-
 int ir_regs_number(void)
 {
 	return IR_REG_NUM;
@@ -1599,9 +1595,7 @@ static ir_reg ir_try_allocate_free_reg(ir_ctx *ctx, ir_live_interval *ival, ir_l
 		}
 	}
 
-#ifdef IR_DEBUG_REGSET
+	available = IR_REGSET_DIFFERENCE(available, (ir_regset)ctx->fixed_regset);
-	available &= debug_regset;
-#endif
 
 	/* for each interval it in active */
 	other = *active;
@@ -1741,9 +1735,7 @@ static ir_reg ir_allocate_blocked_reg(ir_ctx *ctx, ir_live_interval *ival, ir_li
 		}
 	}
 
-#ifdef IR_DEBUG_REGSET
+	available = IR_REGSET_DIFFERENCE(available, (ir_regset)ctx->fixed_regset);
-	available &= debug_regset;
-#endif
 
 	if (IR_REGSET_IS_EMPTY(available)) {
 		fprintf(stderr, "LSRA Internal Error: No registers available. Allocation is not possible\n");

ir_test.c

@@ -124,6 +124,7 @@ int main(int argc, char **argv)
     int i;
 	int opt_level = 2;
 	uint32_t mflags = 0;
+	uint64_t debug_regset = 0xffffffffffffffff;
 
 	ir_consistency_check();
 
@@ -152,7 +153,6 @@ int main(int argc, char **argv)
 		} else if (strcmp(argv[i], "--debug-ra") == 0) {
 			mflags |= IR_DEBUG_RA;
 #endif
-#ifdef IR_DEBUG_REGSET
 		} else if (strcmp(argv[i], "--debug-regset") == 0) {
 			if (i + 1 == argc || argv[i + 1][0] == '-') {
 				fprintf(stderr, "ERROR: Invalid usage' (use --help)\n");
@@ -160,7 +160,6 @@ int main(int argc, char **argv)
 			}
 			debug_regset = strtoull(argv[i + 1], NULL, 0);
 			i++;
-#endif
 		} else {
 			/* pass*/
 		}
@@ -172,6 +171,7 @@ int main(int argc, char **argv)
 	if (opt_level > 0) {
 		ctx.flags |= IR_OPT_FOLDING | IR_OPT_CODEGEN;
 	}
+	ctx.fixed_regset = ~debug_regset;
     gen_mandelbrot(&ctx);
 
 	ir_build_def_use_lists(&ctx);