Fix yielding value from throw

Author: msimacek

graalpython/com.oracle.graal.python.test/testData/goldenFiles/CompilerTests/testCoroutine.co

@@ -10,11 +10,11 @@ Flags: CO_COROUTINE
 000022         2 GET_AWAITABLE
 000022         3 LOAD_NONE
 000022   >>    4 SEND                              10   (to 14)
-000022         6 YIELD_VALUE
+000022   >>    6 YIELD_VALUE
 000022         7 RESUME_YIELD
 000022         8 JUMP_BACKWARD                     4    (to 4)
 000022        10 THROW                             4                                     (exc handler 7 - 10; stack: 1)
-000022        12 JUMP_BACKWARD                     8    (to 4)
+000022        12 JUMP_BACKWARD                     6    (to 6)
 000022   >>   14 POP_TOP
 000000        15 LOAD_NONE
 000000        16 RETURN_VALUE

graalpython/com.oracle.graal.python.test/testData/goldenFiles/CompilerTests/testYieldFrom.co

@@ -10,11 +10,11 @@ Flags: CO_GENERATOR
 000016         2 GET_ITER
 000016         3 LOAD_NONE
 000016   >>    4 SEND                              10   (to 14)
-000016         6 YIELD_VALUE
+000016   >>    6 YIELD_VALUE
 000016         7 RESUME_YIELD
 000016         8 JUMP_BACKWARD                     4    (to 4)
 000016        10 THROW                             4                                     (exc handler 7 - 10; stack: 1)
-000016        12 JUMP_BACKWARD                     8    (to 4)
+000016        12 JUMP_BACKWARD                     6    (to 6)
 000016   >>   14 POP_TOP
 000000        15 LOAD_NONE
 000000        16 RETURN_VALUE

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/compiler/Compiler.java

@@ -1453,11 +1453,13 @@ public Void visit(ExprTy.YieldFrom node) {
 
     private void addYieldFrom() {
         Block start = new Block();
+        Block yield = new Block();
         Block resume = new Block();
         Block exit = new Block();
         Block exceptionHandler = new Block();
         unit.useNextBlock(start);
         addOp(SEND, exit);
+        unit.useNextBlock(yield);
         addOp(YIELD_VALUE);
         unit.pushBlock(new BlockInfo.TryExcept(resume, exceptionHandler));
         unit.useNextBlock(resume);
@@ -1466,7 +1468,7 @@ private void addYieldFrom() {
         unit.popBlock();
         unit.useNextBlock(exceptionHandler);
         addOp(THROW, exit);
-        addOp(JUMP_BACKWARD, start);
+        addOp(JUMP_BACKWARD, yield);
         unit.useNextBlock(exit);
     }