Transfer functions for overflow insts (#695)

google · Jan 27, 2020 · 64eff6f · 64eff6f
1 parent 09efbd5
commit 64eff6f
Showing 1 changed file with 48 additions and 20 deletions.
diff --git a/lib/Infer/AbstractInterpreter.cpp b/lib/Infer/AbstractInterpreter.cpp
@@ -686,30 +686,34 @@ namespace souper {
       }
       break;
     }
-//   case ExtractValue:
-//     return "extractvalue";
-//   case SAddWithOverflow:
-//     return "sadd.with.overflow";
-//   case UAddWithOverflow:
-//     return "uadd.with.overflow";
-//   case SSubWithOverflow:
-//     return "ssub.with.overflow";
-//   case USubWithOverflow:
-//     return "usub.with.overflow";
-//   case SMulWithOverflow:
-//     return "smul.with.overflow";
-//   case UMulWithOverflow:
-//     return "umul.with.overflow";
+    case souper::Inst::ExtractValue: {
+      if (I->Ops[1]->Val == 0) {
+        auto IOld = I;
+        I = I->Ops[0]->Ops[0];
+        switch (IOld->Ops[0]->K) {
+          case souper::Inst::SAddWithOverflow:
+          case souper::Inst::UAddWithOverflow:
+            return BinaryTransferFunctionsKB::add(KB0, KB1);
+
+          case souper::Inst::SSubWithOverflow:
+          case souper::Inst::USubWithOverflow:
+            return BinaryTransferFunctionsKB::sub(KB0, KB1);
+
+          case souper::Inst::SMulWithOverflow:
+          case souper::Inst::UMulWithOverflow:
+            return BinaryTransferFunctionsKB::mul(KB0, KB1);
+          default:
+            llvm::report_fatal_error("Wrong operand in ExtractValue.");
+        }
+        I = IOld; // needed for caching
+      }
+      // returns TOP for the carry bit
+    }
+
 //   case ReservedConst:
 //     return "reservedconst";
 //   case ReservedInst:
 //     return "reservedinst";
-//   case SAddO:
-//   case UAddO:
-//   case SSubO:
-//   case USubO:
-//   case SMulO:
-//   case UMulO:
     default :
       break;
     }
@@ -858,6 +862,30 @@ namespace souper {
       //       return R0.sdiv(R1); // unimplemented
       //     }
       // TODO: Xor pattern for not, truncs and extends, etc
+    case souper::Inst::ExtractValue: {
+      if (I->Ops[1]->Val == 0) {
+        auto IOld = I;
+        I = I->Ops[0]->Ops[0];
+        switch (IOld->Ops[0]->K) {
+          case souper::Inst::SAddWithOverflow:
+          case souper::Inst::UAddWithOverflow:
+            return CR0.add(CR1);
+
+          case souper::Inst::SSubWithOverflow:
+          case souper::Inst::USubWithOverflow:
+            return CR0.sub(CR1);
+
+          case souper::Inst::SMulWithOverflow:
+          case souper::Inst::UMulWithOverflow:
+            return CR0.multiply(CR1);
+          default:
+            llvm::errs() << Inst::getKindName(I->Ops[0]->K) << "\n";
+            llvm::report_fatal_error("Wrong operand in ExtractValue.");
+        }
+        I = IOld; // needed for caching
+      }
+      // returns TOP for the carry bit
+    }
     default:
       break;
     }