Better syntax for conditionals and switch/case constructions ##decomp…

…iler
radareorg · Jun 11, 2024 · 7db2313 · 7db2313
1 parent 237f0c7
commit 7db2313
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Showing 3 changed files with 41 additions and 15 deletions.
diff --git a/libr/arch/p/arm/pseudo.c b/libr/arch/p/arm/pseudo.c
@@ -40,8 +40,10 @@ static int replace(int argc, const char *argv[], char *newstr) {
 		{ 0, "cbz", "if !# goto #", { 1, 2 } },
 		{ 0, "cbnz", "if # goto #", { 1, 2 } },
 		{ 0, "b.w", "goto #", { 1 } },
-		{ 0, "b.gt", "goto ifgt #", { 1 } },
-		{ 0, "b.le", "goto ifle #", { 1 } },
+		{ 0, "b.gt", "if (a > b) #", { 1 } },
+		{ 0, "b.le", "if (a <= b) #", { 1 } },
+		{ 0, "b.lt", "if (a < b) #", { 1 } },
+		{ 0, "b.ge", "if (a >= b) #", { 1 } },
 		{ 0, "beq lr", "ifeq ret", {0} },
 		{ 0, "beq", "je #", { 1 } },
 		{ 0, "call", "# ()", { 1 } },
@@ -56,9 +58,12 @@ static int replace(int argc, const char *argv[], char *newstr) {
 		{ 0, "b.lo", "goto iflt #", { 1 } },
 		{ 0, "cmf", "if (# == #)", { 1, 2 } },
 		{ 0, "cmn", "if (# != #)", { 1, 2 } },
-		{ 0, "cmp", "if (# == #)", { 1, 2 } },
-		{ 0, "fcmp", "if (# == #)", { 1, 2 } },
-		{ 0, "tst", "if ((# & #) == 0)", { 1, 2 } },
+		{ 0, "cmp", "(a, b) = compare (#, #)", { 1, 2 } },
+		{ 0, "fcmp", "(a, b) = compare (#, #)", { 1, 2 } },
+		{ 0, "tst", "(a, b) = compare (#, #)", { 1, 2 } },
+		// { 0, "cmp", "if (# == #)", { 1, 2 } },
+		// { 0, "fcmp", "if (# == #)", { 1, 2 } },
+		//{ 0, "tst", "if ((# & #) == 0)", { 1, 2 } },
 		{ 4, "csel", "# = (#)? # : #", { 1, 4, 2, 3 } },
 		{ 2, "cset", "# = (#)? 1 : 0", { 1, 2 } },
 		{ 0, "dvf", "# = # / #", { 1, 2, 3 } },

diff --git a/libr/core/pseudo.c b/libr/core/pseudo.c
@@ -410,7 +410,7 @@ R_API int r_core_pseudo_code(RCore *core, const char *input) {
 			}
 		} else {
 			NEWLINE (bb->addr, indent);
-			PRINTF ("goto loc_0x%"PFMT64x, bb->fail);
+			PRINTF ("goto loc_0x%"PFMT64x";", bb->fail);
 		}
 		if (sdb_const_get (db, K_INDENT (bb->addr), 0)) {
 			// already analyzed, go pop and continue
@@ -549,10 +549,12 @@ R_API int r_core_pseudo_code(RCore *core, const char *input) {
 					}
 				}
 				PRINTF ("goto loc_0x%"PFMT64x";", bb->fail);
+#if 0
 				if (nindent != indent) {
 					NEWLINE (bb->addr, indent);
 					PRINTF ("} else {");
 				}
+#endif
 				indent = nindent;
 			}
 			PRINTGOTO (bb->addr, gotoaddr);
@@ -577,7 +579,13 @@ R_API int r_core_pseudo_code(RCore *core, const char *input) {
 			r_config_set_b (core->config, "scr.html", true);
 		}
 		s = r_str_replace (s, ";", "//", true);
-		s = r_str_replace (s, "goto ", "goto loc_", true);
+		char *lastgoto = strstr (s, "goto ");
+		if (lastgoto) {
+			if (!strchr (lastgoto, '\n')) {
+				*s = 0;
+			}
+		}
+		s = r_str_replace (s, "goto ", "// goto loc_", true);
 		if (show_addr) {
 			// indent with | or stgh
 			char *os = r_str_prefix_all (s, " ");
@@ -609,7 +617,20 @@ R_API int r_core_pseudo_code(RCore *core, const char *input) {
 			} else {
 				NEWLINE (bb->addr, 1);
 			}
-			PRINTF ("loc_0x%08"PFMT64x": // orphan\n%s", bb->addr, s);
+			RFlagItem *fi = r_flag_get_i (core->flags, bb->addr);
+			if (fi && r_str_startswith (fi->name, "case.")) {
+				const char *val = r_str_lchr (fi->name, '.') + 1;
+				char *hex = r_str_newf ("0x%s", val);
+				int nval = r_num_get (NULL, hex);
+				free (hex);
+				if (IS_PRINTABLE (nval)) {
+					PRINTF ("loc_0x%08"PFMT64x": // case '%c'\n%s", bb->addr, nval, s);
+				} else {
+					PRINTF ("loc_0x%08"PFMT64x": // case %s\n%s", bb->addr, val, s);
+				}
+			} else {
+				PRINTF ("loc_0x%08"PFMT64x": // orphan\n%s", bb->addr, s);
+			}
 			ut64 nbbaddr = UT64_MAX;
 			if (iter->n) {
 				RAnalBlock *nbb = (RAnalBlock*)iter->n;

diff --git a/test/db/cmd/cmd_pdc b/test/db/cmd/cmd_pdc
@@ -121,9 +121,9 @@ int entry0 (int stack, int stack) {
         si-
         var = si - 0
         if  (var > 0) goto loc_0x402018 // unlikely
-        goto loc_0x402042
+        goto loc_0x402042;
          // } while (?);
-        goto loc_0x402042
+        goto loc_0x402042;
         }
         return eax;
     loc_0x402042:
@@ -171,12 +171,12 @@ int sym.func.100003a54 (int x0, int x1) {
         x8 = [x8 + 0x60]
         x9 = [x1 + 0x60] // arg2
         x9 = [x9 + 0x60]
-        if (x8 == x9)
-        goto ifle 0x100003a74 // likely
-        goto loc_0x100003a6c
+        (a, b) = compare (x8, x9)
+        if (a <= b) 0x100003a74 // likely
+        goto loc_0x100003a6c;
     loc_0x100003a74:
-        b.ge 0x100003a80 // likely
-        goto loc_0x100003a78
+        if (a >= b) 0x100003a80 // likely
+        goto loc_0x100003a78;
     loc_0x100003a80:
         x8 = x1 + 0x68 // arg2
         x1 = x0 + 0x68 // arg1