From cbb37dbb2baf8a6fc658ffc0c87fd1d2afa8d3f5 Mon Sep 17 00:00:00 2001
From: Jan de Mooij <jdemooij@mozilla.com>
Date: Wed, 22 Nov 2017 13:06:02 +0100
Subject: [PATCH] Bug 1417399 - Remove unnecessary checks for lazy link stub in
 LazyLinkTopActivation. r=nbp

--HG--
extra : rebase_source : 1be7cb018b682833c2e182fa1c62d4e18769e283
---
 js/src/jit/CodeGenerator.cpp |  2 --
 js/src/jit/Ion.cpp           | 17 +++--------------
 js/src/jit/JitCompartment.h  |  4 ----
 3 files changed, 3 insertions(+), 20 deletions(-)

diff --git a/js/src/jit/CodeGenerator.cpp b/js/src/jit/CodeGenerator.cpp
index 3fa6dd50416d..fdafb755c844 100644
--- a/js/src/jit/CodeGenerator.cpp
+++ b/js/src/jit/CodeGenerator.cpp
@@ -8029,8 +8029,6 @@ JitRuntime::generateLazyLinkStub(MacroAssembler& masm)
     masm.popReturnAddress();
 #endif
     masm.jump(ReturnReg);
-
-    lazyLinkStubEndOffset_ = masm.currentOffset();
 }
 
 void
diff --git a/js/src/jit/Ion.cpp b/js/src/jit/Ion.cpp
index 73232290cbfa..2df932dc4c33 100644
--- a/js/src/jit/Ion.cpp
+++ b/js/src/jit/Ion.cpp
@@ -203,7 +203,6 @@ JitRuntime::JitRuntime(JSRuntime* rt)
     argumentsRectifierReturnOffset_(0),
     invalidatorOffset_(0),
     lazyLinkStubOffset_(0),
-    lazyLinkStubEndOffset_(0),
     interpreterStubOffset_(0),
     debugTrapHandler_(nullptr),
     baselineDebugModeOSRHandler_(nullptr),
@@ -2799,17 +2798,8 @@ InvalidateActivation(FreeOp* fop, const JitActivationIterator& activations, bool
         if (!frame.isIonScripted())
             continue;
 
-        JitRuntime* jrt = fop->runtime()->jitRuntime();
-
-        bool calledFromLinkStub = false;
-        if (frame.returnAddressToFp() >= jrt->lazyLinkStub().value &&
-            frame.returnAddressToFp() < jrt->lazyLinkStubEnd().value)
-        {
-            calledFromLinkStub = true;
-        }
-
         // See if the frame has already been invalidated.
-        if (!calledFromLinkStub && frame.checkInvalidation())
+        if (frame.checkInvalidation())
             continue;
 
         JSScript* script = frame.script();
@@ -2866,9 +2856,8 @@ InvalidateActivation(FreeOp* fop, const JitActivationIterator& activations, bool
         }
         ionCode->setInvalidated();
 
-        // Don't adjust OSI points in the linkStub (which don't exist), or in a
-        // bailout path.
-        if (calledFromLinkStub || frame.isBailoutJS())
+        // Don't adjust OSI points in a bailout path.
+        if (frame.isBailoutJS())
             continue;
 
         // Write the delta (from the return address offset to the
diff --git a/js/src/jit/JitCompartment.h b/js/src/jit/JitCompartment.h
index fde4fbdd9330..1b1599b8ccf6 100644
--- a/js/src/jit/JitCompartment.h
+++ b/js/src/jit/JitCompartment.h
@@ -134,7 +134,6 @@ class JitRuntime
 
     // Thunk called to finish compilation of an IonScript.
     ExclusiveAccessLockWriteOnceData<uint32_t> lazyLinkStubOffset_;
-    ExclusiveAccessLockWriteOnceData<uint32_t> lazyLinkStubEndOffset_;
 
     // Thunk to enter the interpreter from JIT code.
     ExclusiveAccessLockWriteOnceData<uint32_t> interpreterStubOffset_;
@@ -315,9 +314,6 @@ class JitRuntime
     TrampolinePtr lazyLinkStub() const {
         return trampolineCode(lazyLinkStubOffset_);
     }
-    TrampolinePtr lazyLinkStubEnd() const {
-        return trampolineCode(lazyLinkStubEndOffset_);
-    }
     TrampolinePtr interpreterStub() const {
         return trampolineCode(interpreterStubOffset_);
     }