Bug 1147371: Implement JSOP_PICK and JSOP_UNPICK in the expression decompiler

Issue mcp-graveyard/UXP#74

1 files changed, 28 insertions, 0 deletions

diff --git a/js/src/jsopcode.cpp b/js/src/jsopcode.cpp
index 31bbfb4717..eadbca4f81 100644
--- a/js/src/jsopcode.cpp
+++ b/js/src/jsopcode.cpp
@@ -460,6 +460,34 @@ BytecodeParser::simulateOp(JSOp op, uint32_t offset, uint32_t* offsetStack, uint
             offsetStack[stackDepth] = tmp;
         }
         break;
+
+      case JSOP_PICK: {
+        jsbytecode* pc = script_->offsetToPC(offset);
+        unsigned n = GET_UINT8(pc);
+        MOZ_ASSERT(ndefs == n + 1);
+        if (offsetStack) {
+            uint32_t top = stackDepth + n;
+            uint32_t tmp = offsetStack[stackDepth];
+            for (uint32_t i = stackDepth; i < top; i++)
+                offsetStack[i] = offsetStack[i + 1];
+            offsetStack[top] = tmp;
+        }
+        break;
+      }
+
+      case JSOP_UNPICK: {
+        jsbytecode* pc = script_->offsetToPC(offset);
+        unsigned n = GET_UINT8(pc);
+        MOZ_ASSERT(ndefs == n + 1);
+        if (offsetStack) {
+            uint32_t top = stackDepth + n;
+            uint32_t tmp = offsetStack[top];
+            for (uint32_t i = top; i > stackDepth; i--)
+                offsetStack[i] = offsetStack[i - 1];
+            offsetStack[stackDepth] = tmp;
+        }
+        break;
+      }
     }
     stackDepth += ndefs;
     return stackDepth;