libmach

1 files changed, 138 insertions, 0 deletions

diff --git a/src/libmach/dwarfdump.c b/src/libmach/dwarfdump.c
new file mode 100644
index 00000000..47c38c37
--- /dev/null
+++ b/src/libmach/dwarfdump.c
@@ -0,0 +1,138 @@
+#include <u.h>
+#include <libc.h>
+#include <bio.h>
+#include "elf.h"
+#include "dwarf.h"
+
+void printrules(Dwarf *d, ulong pc);
+int exprfmt(Fmt*);
+
+void
+usage(void)
+{
+	fprint(2, "usage: dwarfdump file\n");
+	exits("usage");
+}
+
+void
+main(int argc, char **argv)
+{
+	int c;
+	Elf *elf;
+	Dwarf *d;
+	DwarfSym s;
+	char *cdir, *dir, *file;
+	ulong line, mtime, length;
+
+	ARGBEGIN{
+	default:
+		usage();
+	}ARGEND
+
+	if(argc != 1)
+		usage();
+
+	fmtinstall('R', exprfmt);
+	fmtinstall('H', encodefmt);
+
+	if((elf = elfopen(argv[0])) == nil)
+		sysfatal("elfopen %s: %r", argv[0]);
+	if((d=dwarfopen(elf)) == nil)
+		sysfatal("dwarfopen: %r");
+
+	if(dwarfenum(d, &s) < 0)
+		sysfatal("dwarfenumall: %r");
+
+	while(dwarfnextsym(d, &s, 1) == 1){
+		switch(s.attrs.tag){
+		case TagCompileUnit:
+			print("compileunit %s\n", s.attrs.name);
+			break;
+		case TagSubprogram:
+			c = 't';
+			goto sym;
+		case TagVariable:
+			c = 'd';
+			goto sym;
+		case TagConstant:
+			c = 'c';
+			goto sym;
+		case TagFormalParameter:
+			if(!s.attrs.name)
+				break;
+			c = 'p';
+		sym:
+			if(s.attrs.isexternal)
+				c += 'A' - 'a';
+			print("%c %s", c, s.attrs.name);
+			if(s.attrs.have.lowpc)
+				print(" 0x%lux-0x%lux", s.attrs.lowpc, s.attrs.highpc);
+			switch(s.attrs.have.location){
+			case TBlock:
+				print(" @ %.*H", s.attrs.location.b.len, s.attrs.location.b.data);
+				break;
+			case TConstant:
+				print(" @ 0x%lux", s.attrs.location.c);
+				break;
+			}
+			if(s.attrs.have.ranges)
+				print(" ranges@0x%lux", s.attrs.ranges);
+			print("\n");
+			if(s.attrs.have.lowpc){
+				if(dwarfpctoline(d, s.attrs.lowpc, &cdir, &dir, &file, &line, &mtime, &length) < 0)
+					print("\tcould not find source: %r\n");
+				else
+					print("\t%s/%s/%s:%lud mtime=%lud length=%lud\n",
+						cdir, dir, file, line, mtime, length);
+
+				if(0) printrules(d, s.attrs.lowpc);
+				if(0) printrules(d, (s.attrs.lowpc+s.attrs.highpc)/2);
+			}
+			break;
+		}
+	}
+	exits(0);
+}
+
+void
+printrules(Dwarf *d, ulong pc)
+{
+	int i;
+	DwarfExpr r[10];
+	DwarfExpr cfa, ra;
+
+	if(dwarfunwind(d, pc, &cfa, &ra, r, nelem(r)) < 0)
+		print("\tcannot unwind from pc 0x%lux: %r\n", pc);
+
+	print("\tpc=0x%lux cfa=%R ra=%R", pc, &cfa, &ra);
+	for(i=0; i<nelem(r); i++)
+		if(r[i].type != RuleSame)
+			print(" r%d=%R", i, &r[i]);
+	print("\n");
+}
+
+int
+exprfmt(Fmt *fmt)
+{
+	DwarfExpr *e;
+
+	if((e = va_arg(fmt->args, DwarfExpr*)) == nil)
+		return fmtstrcpy(fmt, "<nil>");
+
+	switch(e->type){
+	case RuleUndef:
+		return fmtstrcpy(fmt, "undef");
+	case RuleSame:
+		return fmtstrcpy(fmt, "same");
+	case RuleCfaOffset:
+		return fmtprint(fmt, "%ld(cfa)", e->offset);
+	case RuleRegister:
+		return fmtprint(fmt, "r%ld", e->reg);
+	case RuleRegOff:
+		return fmtprint(fmt, "%ld(r%ld)", e->offset, e->reg);
+	case RuleLocation:
+		return fmtprint(fmt, "l.%.*H", e->loc.len, e->loc.data);
+	default:
+		return fmtprint(fmt, "?%d", e->type);
+	}
+}