tor-browser

commit 4ef5ff63b2fd3ec569436a7016b64d767c1a25fa
parent ad2c07b35ec9ac10030b63aa9e896538fad5ebd3
Author: Rong "Mantle" Bao <webmaster@csmantle.top>
Date:   Mon,  5 Jan 2026 15:30:18 +0000

Bug 2008301 - [loong64] Part 1: Defer scratch allocation in demanding atomic ops for loong64. r=jandem

Differential Revision: https://phabricator.services.mozilla.com/D277737

Diffstat:
M
js/src/jit/loong64/MacroAssembler-loong64.cpp
 | 
17
+++++++++++------

1 file changed, 11 insertions(+), 6 deletions(-)
diff --git a/js/src/jit/loong64/MacroAssembler-loong64.cpp b/js/src/jit/loong64/MacroAssembler-loong64.cpp
@@ -3615,8 +3615,6 @@ static void CompareExchange(MacroAssembler& masm,
                             Register valueTemp, Register offsetTemp,
                             Register maskTemp, Register output) {
   UseScratchRegisterScope temps(masm);
-  Register scratch = temps.Acquire();
-  Register scratch2 = temps.Acquire();
   bool signExtend = Scalar::isSignedIntType(type);
   unsigned nbytes = Scalar::byteSize(type);
 
@@ -3635,8 +3633,11 @@ static void CompareExchange(MacroAssembler& masm,
 
   Label again, end;
 
+  Register scratch = temps.Acquire();
   masm.computeEffectiveAddress(mem, scratch);
 
+  Register scratch2 = temps.Acquire();
+
   if (nbytes == 4) {
     masm.memoryBarrierBefore(sync);
     masm.bind(&again);
@@ -3725,9 +3726,10 @@ static void CompareExchange64(MacroAssembler& masm,
   MOZ_ASSERT(expect != output && replace != output);
   UseScratchRegisterScope temps(masm);
   Register scratch = temps.Acquire();
-  Register scratch2 = temps.Acquire();
   masm.computeEffectiveAddress(mem, scratch);
 
+  Register scratch2 = temps.Acquire();
+
   Label tryAgain;
   Label exit;
 
@@ -3865,10 +3867,12 @@ static void AtomicExchange64(MacroAssembler& masm,
                              Register64 value, Register64 output) {
   MOZ_ASSERT(value != output);
   UseScratchRegisterScope temps(masm);
+
   Register scratch = temps.Acquire();
-  Register scratch2 = temps.Acquire();
   masm.computeEffectiveAddress(mem, scratch);
 
+  Register scratch2 = temps.Acquire();
+
   Label tryAgain;
 
   masm.memoryBarrierBefore(sync);
@@ -4263,8 +4267,6 @@ static void AtomicEffectOp(MacroAssembler& masm,
                            const T& mem, Register value, Register valueTemp,
                            Register offsetTemp, Register maskTemp) {
   UseScratchRegisterScope temps(masm);
-  Register scratch = temps.Acquire();
-  Register scratch2 = temps.Acquire();
   unsigned nbytes = Scalar::byteSize(type);
 
   switch (nbytes) {
@@ -4282,8 +4284,11 @@ static void AtomicEffectOp(MacroAssembler& masm,
 
   Label again;
 
+  Register scratch = temps.Acquire();
   masm.computeEffectiveAddress(mem, scratch);
 
+  Register scratch2 = temps.Acquire();
+
   if (nbytes == 4) {
     masm.memoryBarrierBefore(sync);
     masm.bind(&again);