[IRInterpreter] Fix misevaluation of interpretation expressions with urem.

dcci · dcci · commit a9d84cb9d8fb · 2018-07-12T00:31:04.000Z
Scalar::MakeUnsigned was implemented incorrectly so it didn't really change the sign of the type (leaving signed types signed). This showed up as a misevaluation when IR-interpreting urem but it's likely to arise in other contexts. This commit fixes the definition, and adds a test to make sure this won't regress in future (hopefully). Fixes rdar://problem/42038760 and LLVM PR38076 Differential Revision: https://reviews.llvm.org/D49155 llvm-svn: 336872
diff --git a/lldb/packages/Python/lldbsuite/test/expression_command/rdar42038760/Makefile b/lldb/packages/Python/lldbsuite/test/expression_command/rdar42038760/Makefile
@@ -0,0 +1,3 @@
+LEVEL = ../../make
+C_SOURCES := main.c
+include $(LEVEL)/Makefile.rules
diff --git a/lldb/packages/Python/lldbsuite/test/expression_command/rdar42038760/TestScalarURem.py b/lldb/packages/Python/lldbsuite/test/expression_command/rdar42038760/TestScalarURem.py
@@ -0,0 +1,4 @@
+from lldbsuite.test import lldbinline
+from lldbsuite.test import decorators
+
+lldbinline.MakeInlineTest(__file__, globals(), None)
diff --git a/lldb/packages/Python/lldbsuite/test/expression_command/rdar42038760/main.c b/lldb/packages/Python/lldbsuite/test/expression_command/rdar42038760/main.c
@@ -0,0 +1,19 @@
+// Make sure we IR-interpret the expression correctly.
+
+typedef unsigned int uint32_t;
+struct S0 {
+  signed f2;
+};
+static g_463 = 0x1561983AL;
+void func_1(void)
+{
+  struct S0 l_19;
+  l_19.f2 = 419;
+  uint32_t l_4037 = 4294967295UL;
+  l_19.f2 = g_463; //%self.expect("expr ((l_4037 % (-(g_463))) | l_19.f2)", substrs=['(unsigned int) $0 = 358717883'])
+}
+int main()
+{
+  func_1();
+  return 0;
+}
diff --git a/lldb/source/Core/Scalar.cpp b/lldb/source/Core/Scalar.cpp
@@ -1184,38 +1184,38 @@ bool Scalar::MakeUnsigned() {
   case e_void:
     break;
   case e_sint:
+    m_type = e_uint;
     success = true;
     break;
   case e_uint:
-    m_type = e_uint;
     success = true;
     break;
   case e_slong:
+    m_type = e_ulong;
     success = true;
     break;
   case e_ulong:
-    m_type = e_ulong;
     success = true;
     break;
   case e_slonglong:
+    m_type = e_ulonglong;
     success = true;
     break;
   case e_ulonglong:
-    m_type = e_ulonglong;
     success = true;
     break;
   case e_sint128:
+    m_type = e_uint128;
     success = true;
     break;
   case e_uint128:
-    m_type = e_uint128;
     success = true;
     break;
   case e_sint256:
+    m_type = e_uint256;
     success = true;
     break;
   case e_uint256:
-    m_type = e_uint256;
     success = true;
     break;
   case e_float:

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+LEVEL = ../../make`
	`2`	`+C_SOURCES := main.c`
	`3`	`+include $(LEVEL)/Makefile.rules`