Commit 64a0510205b4d224413de52fd87632fbe6bfe083 | zig

author	Andrew Kelley <andrew@ziglang.org> 2017-02-04 22:33:58-05:00
committer	Andrew Kelley <andrew@ziglang.org> 2017-02-04 22:33:58-05:00
log	64a0510205b4d224413de52fd87632fbe6bfe083
tree	c673e98af23f82d939ec0513bfbf8f757704a9a6
parent	b840184bb09b9d5e4272f848dcaa7c4973dfdcd5

inline assembly supports `%=` syntax

it outputs a number that is unique to each instance of the asm
statement in the entire compilation.

useful when creating local labels and referring to them multiple
times in a single template that generates multiple
assembler instructions

3 files changed, 18 insertions(+), 3 deletions(-)

src/all_types.hpp+3

...	...	@@ -604,6 +604,7 @@ enum AsmTokenId {
604	604	AsmTokenIdTemplate,
605	605	AsmTokenIdPercent,
606	606	AsmTokenIdVar,
	607	AsmTokenIdUniqueId,
607	608	};
608	609
609	610	struct AsmToken {
...	...	@@ -1286,6 +1287,8 @@ struct CodeGen {
1286	1287
1287	1288	IrInstruction *invalid_instruction;
1288	1289	ConstExprValue const_void_val;
	1290
	1291	uint32_t unique_asm_id;
1289	1292	};
1290	1293
1291	1294	enum VarLinkage {

src/codegen.cpp+11-3

...	...	@@ -1481,6 +1481,9 @@ static LLVMValueRef ir_render_asm(CodeGen g, IrExecutable executable, IrInstru
1481	1481	Buf llvm_template = BUF_INIT;
1482	1482	buf_resize(&llvm_template, 0);
1483	1483
	1484	uint32_t unique_id = g->unique_asm_id;
	1485	g->unique_asm_id += 1;
	1486
1484	1487	for (size_t token_i = 0; token_i < asm_expr->token_list.length; token_i += 1) {
1485	1488	AsmToken *asm_token = &asm_expr->token_list.at(token_i);
1486	1489	switch (asm_token->id) {
...	...	@@ -1498,9 +1501,14 @@ static LLVMValueRef ir_render_asm(CodeGen g, IrExecutable executable, IrInstru
1498	1501	buf_append_char(&llvm_template, '%');
1499	1502	break;
1500	1503	case AsmTokenIdVar:
1501		size_t index = find_asm_index(g, asm_node, asm_token);
1502		assert(index < SIZE_MAX);
1503		buf_appendf(&llvm_template, "$%zu", index);
	1504	{
	1505	size_t index = find_asm_index(g, asm_node, asm_token);
	1506	assert(index < SIZE_MAX);
	1507	buf_appendf(&llvm_template, "$%zu", index);
	1508	break;
	1509	}
	1510	case AsmTokenIdUniqueId:
	1511	buf_appendf(&llvm_template, "%" PRIu32, unique_id);
1504	1512	break;
1505	1513	}
1506	1514	}

src/parser.cpp+4

...	...	@@ -136,6 +136,10 @@ static void parse_asm_template(ParseContext pc, AstNode node) {
136	136	} else if (c == '[') {
137	137	cur_tok->id = AsmTokenIdVar;
138	138	state = StateVar;
	139	} else if (c == '=') {
	140	cur_tok->id = AsmTokenIdUniqueId;
	141	cur_tok->end = i;
	142	state = StateStart;
139	143	} else {
140	144	ast_asm_error(pc, node, i, "expected a '%%' or '['");
141	145	}