tor-browser

commit 59023469376c0c56bcd0b8d66bce8359bd427659
parent 21a87fad7ce2fc34cc7af996de29f7d19020c2a6
Author: Jan de Mooij <jdemooij@mozilla.com>
Date:   Fri, 12 Dec 2025 10:35:54 +0000

Bug 2005479 part 6 - Use generate_lir: true for ResizableTypedArrayLength and ResizableDataViewByteLength. r=iain

Move SynchronizeLoad and SynchronizeStore helper functions from
Lowering.cpp to MIR.h so they can be used from both CodeGenerator and
Lowering.

Differential Revision: https://phabricator.services.mozilla.com/D276050

Diffstat:
M
js/src/jit/CodeGenerator.cpp
 | 
8
++++----
M
js/src/jit/LIROps.yaml
 | 
18
------------------
M
js/src/jit/Lowering.cpp
 | 
20
++------------------
M
js/src/jit/MIR.h
 | 
16
++++++++++++++++
M
js/src/jit/MIROps.yaml
 | 
4
++++

5 files changed, 26 insertions(+), 40 deletions(-)
diff --git a/js/src/jit/CodeGenerator.cpp b/js/src/jit/CodeGenerator.cpp
@@ -11502,8 +11502,8 @@ void CodeGenerator::visitResizableTypedArrayLength(
   Register out = ToRegister(lir->output());
   Register temp = ToRegister(lir->temp0());
 
-  masm.loadResizableTypedArrayLengthIntPtr(lir->synchronization(), obj, out,
-                                           temp);
+  auto sync = SynchronizeLoad(lir->mir()->requiresMemoryBarrier());
+  masm.loadResizableTypedArrayLengthIntPtr(sync, obj, out, temp);
 }
 
 void CodeGenerator::visitResizableDataViewByteLength(
@@ -11512,8 +11512,8 @@ void CodeGenerator::visitResizableDataViewByteLength(
   Register out = ToRegister(lir->output());
   Register temp = ToRegister(lir->temp0());
 
-  masm.loadResizableDataViewByteLengthIntPtr(lir->synchronization(), obj, out,
-                                             temp);
+  auto sync = SynchronizeLoad(lir->mir()->requiresMemoryBarrier());
+  masm.loadResizableDataViewByteLengthIntPtr(sync, obj, out, temp);
 }
 
 void CodeGenerator::visitGrowableSharedArrayBufferByteLength(
diff --git a/js/src/jit/LIROps.yaml b/js/src/jit/LIROps.yaml
@@ -1964,24 +1964,6 @@
   num_temps: 3
   mir_op: true
 
-# Read the length of a resizable typed array.
-- name: ResizableTypedArrayLength
-  result_type: WordSized
-  operands:
-    object: WordSized
-  arguments:
-    synchronization: js::jit::Synchronization
-  num_temps: 1
-
-# Read the byte length of a resizable data view.
-- name: ResizableDataViewByteLength
-  result_type: WordSized
-  operands:
-    object: WordSized
-  arguments:
-    synchronization: js::jit::Synchronization
-  num_temps: 1
-
 # Double to IntPtr, eligible for accessing into a TypedArray or DataView. If
 # the index isn't exactly representable as an IntPtr, depending on the
 # supportOOB flag on the MIR instruction, either bail out or produce an IntPtr
diff --git a/js/src/jit/Lowering.cpp b/js/src/jit/Lowering.cpp
@@ -4458,20 +4458,6 @@ void LIRGenerator::visitGetNextEntryForIterator(MGetNextEntryForIterator* ins) {
   define(lir, ins);
 }
 
-static auto SynchronizeLoad(MemoryBarrierRequirement requiresBarrier) {
-  if (requiresBarrier == MemoryBarrierRequirement::Required) {
-    return Synchronization::Load();
-  }
-  return Synchronization::None();
-}
-
-static auto SynchronizeStore(MemoryBarrierRequirement requiresBarrier) {
-  if (requiresBarrier == MemoryBarrierRequirement::Required) {
-    return Synchronization::Store();
-  }
-  return Synchronization::None();
-}
-
 void LIRGenerator::visitArrayBufferByteLength(MArrayBufferByteLength* ins) {
   MOZ_ASSERT(ins->object()->type() == MIRType::Object);
   MOZ_ASSERT(ins->type() == MIRType::IntPtr);
@@ -4530,9 +4516,8 @@ void LIRGenerator::visitResizableTypedArrayLength(
   MOZ_ASSERT(ins->object()->type() == MIRType::Object);
   MOZ_ASSERT(ins->type() == MIRType::IntPtr);
 
-  auto sync = SynchronizeLoad(ins->requiresMemoryBarrier());
   auto* lir = new (alloc())
-      LResizableTypedArrayLength(useRegister(ins->object()), temp(), sync);
+      LResizableTypedArrayLength(useRegister(ins->object()), temp());
   define(lir, ins);
 }
 
@@ -4541,9 +4526,8 @@ void LIRGenerator::visitResizableDataViewByteLength(
   MOZ_ASSERT(ins->object()->type() == MIRType::Object);
   MOZ_ASSERT(ins->type() == MIRType::IntPtr);
 
-  auto sync = SynchronizeLoad(ins->requiresMemoryBarrier());
   auto* lir = new (alloc())
-      LResizableDataViewByteLength(useRegister(ins->object()), temp(), sync);
+      LResizableDataViewByteLength(useRegister(ins->object()), temp());
   define(lir, ins);
 }
 
diff --git a/js/src/jit/MIR.h b/js/src/jit/MIR.h
@@ -1364,6 +1364,22 @@ enum class MemoryBarrierRequirement : bool {
   Required,
 };
 
+inline Synchronization SynchronizeLoad(
+    MemoryBarrierRequirement requiresBarrier) {
+  if (requiresBarrier == MemoryBarrierRequirement::Required) {
+    return Synchronization::Load();
+  }
+  return Synchronization::None();
+}
+
+inline Synchronization SynchronizeStore(
+    MemoryBarrierRequirement requiresBarrier) {
+  if (requiresBarrier == MemoryBarrierRequirement::Required) {
+    return Synchronization::Store();
+  }
+  return Synchronization::None();
+}
+
 MIR_OPCODE_CLASS_GENERATED
 
 // Truncation barrier. This is intended for protecting its input against
diff --git a/js/src/jit/MIROps.yaml b/js/src/jit/MIROps.yaml
@@ -1842,6 +1842,8 @@
   congruent_to: custom
   alias_set: custom
   compute_range: custom
+  generate_lir: true
+  lir_temps: 1
 
 # Read the byteLength of a resizable dataview.
 - name: ResizableDataViewByteLength
@@ -1856,6 +1858,8 @@
   congruent_to: custom
   alias_set: custom
   compute_range: custom
+  generate_lir: true
+  lir_temps: 1
 
 # Read the byte length of a growable shared array buffer as IntPtr.
 - name: GrowableSharedArrayBufferByteLength