Merge branch 'slice'

* slice: small reorg of OP_SLICE in preparation for some incoming changes

Documentation/IR.rst

@@ -408,7 +408,7 @@ Others
 	Extract a "slice" from an aggregate.
 
 	* .base: (pseudo_t) aggregate (alias .src)
-	* .from, .len: offet & size of the "slice" within the aggregate
+	* .from: offset of the "slice" within the aggregate
 	* .target: result
 	* .type: type of .target
 

evaluate.c

@@ -2170,7 +2170,6 @@ static struct symbol *evaluate_member_dereference(struct expression *expr)
 		}
 		expr->r_bitpos += bytes_to_bits(offset);
 		expr->type = EXPR_SLICE;
-		expr->r_nrbits = member->bit_size;
 		expr->r_bitpos += member->bit_offset;
 		expr->ctype = member;
 		return member;

expression.h

@@ -206,7 +206,7 @@ struct expression {
 		// EXPR_SLICE
 		struct /* slice */ {
 			struct expression *base;
-			unsigned r_bitpos, r_nrbits;
+			unsigned r_bitpos;
 		};
 		// EXPR_CAST, EXPR_FORCE_CAST, EXPR_IMPLIED_CAST,
 		// EXPR_SIZEOF, EXPR_ALIGNOF and EXPR_PTRSIZEOF

linearize.c

@@ -470,7 +470,7 @@ const char *show_instruction(struct instruction *insn)
 		break;
 
 	case OP_SLICE:
-		buf += sprintf(buf, "%s <- %s, %d, %d", show_pseudo(insn->target), show_pseudo(insn->base), insn->from, insn->len);
+		buf += sprintf(buf, "%s <- (%d) %s, %d", show_pseudo(insn->target), type_size(insn->orig_type), show_pseudo(insn->src), insn->from);
 		break;
 
 	case OP_NOT: case OP_NEG:
@@ -1239,8 +1239,8 @@ static pseudo_t linearize_slice(struct entrypoint *ep, struct expression *expr)
 
 	insn->target = new;
 	insn->from = expr->r_bitpos;
-	insn->len = expr->r_nrbits;
-	use_pseudo(insn, pre, &insn->base);
+	insn->orig_type = expr->base->ctype;
+	use_pseudo(insn, pre, &insn->src);
 	add_one_insn(ep, insn);
 	return new;
 }

linearize.h

@@ -113,6 +113,7 @@ struct instruction {
 		};
 		struct /* unops */ {
 			pseudo_t src;
+			unsigned from;			/* slice */
 			struct symbol *orig_type;	/* casts */
 		};
 		struct /* memops */ {
@@ -127,10 +128,6 @@ struct instruction {
 			pseudo_t _src1, _src2;		// alias .src[12]
 			struct symbol *itype;		// input operands' type
 		};
-		struct /* slice */ {
-			pseudo_t base;
-			unsigned from, len;
-		};
 		struct /* setval */ {
 			struct expression *val;
 		};

liveness.c

@@ -76,7 +76,8 @@ static void track_instruction_usage(struct basic_block *bb, struct instruction *
 	/* Uni */
 	case OP_UNOP ... OP_UNOP_END:
 	case OP_SYMADDR:
-		USES(src1); DEFINES(target);
+	case OP_SLICE:
+		USES(src); DEFINES(target);
 		break;
 
 	case OP_SEL:
@@ -121,10 +122,6 @@ static void track_instruction_usage(struct basic_block *bb, struct instruction *
 		} END_FOR_EACH_PTR(pseudo);
 		break;
 
-	case OP_SLICE:
-		USES(base); DEFINES(target);
-		break;
-
 	case OP_ASM:
 		asm_liveness(bb, insn, def, use);
 		break;

show-parse.c

@@ -819,7 +819,7 @@ static int show_slice(struct expression *expr)
 {
 	int target = show_expression(expr->base);
 	int new = new_pseudo();
-	printf("\tslice.%d\t\tv%d,v%d,%d\n", expr->r_nrbits, target, new, expr->r_bitpos);
+	printf("\tslice.%d\t\tv%d,v%d,%d\n", expr->ctype->bit_size, target, new, expr->r_bitpos);
 	return new;
 }