Bug 1138141 - x64: Add some padding after pushing an odd number of float32 registers. r=bbouvier

js/src/jit/shared/MacroAssembler-x86-shared.cpp

@@ -56,6 +56,9 @@ MacroAssembler::PushRegsInMask(RegisterSet set, FloatRegisterSet simdSet)
         storeUnalignedInt32x4(*iter, Address(StackPointer, diffF));
     }
     MOZ_ASSERT(numSimd == 0);
+    // x64 padding to keep the stack aligned on uintptr_t. Keep in sync with
+    // GetPushBytesInSize.
+    diffF -= diffF % sizeof(uintptr_t);
     MOZ_ASSERT(diffF == 0);
 }
 
@@ -101,6 +104,9 @@ MacroAssembler::PopRegsInMaskIgnore(RegisterSet set, RegisterSet ignore, FloatRe
     }
     freeStack(reservedF);
     MOZ_ASSERT(numDouble == 0);
+    // x64 padding to keep the stack aligned on uintptr_t. Keep in sync with
+    // GetPushBytesInSize.
+    diffF -= diffF % sizeof(uintptr_t);
     MOZ_ASSERT(diffF == 0);
 
     // On x86, use pop to pop the integer registers, if we're not going to

js/src/jit/x64/Assembler-x64.cpp

@@ -334,9 +334,16 @@ FloatRegister::GetPushSizeInBytes(const FloatRegisterSet &s)
     SetType set32b = singleSet & ~set64b  & ~set128b;
 
     static_assert(Codes::AllPhysMask <= 0xffff, "We can safely use CountPopulation32");
+    uint32_t count32b = mozilla::CountPopulation32(set32b);
+
+    // If we have an odd number of 32 bits values, then we increase the size to
+    // keep the stack aligned on 8 bytes. Note: Keep in sync with
+    // PushRegsInMask, and PopRegsInMaskIgnore.
+    count32b += count32b & 1;
+
     return mozilla::CountPopulation32(set128b) * (4 * sizeof(int32_t))
         + mozilla::CountPopulation32(set64b) * sizeof(double)
-        + mozilla::CountPopulation32(set32b) * sizeof(float);
+        + count32b * sizeof(float);
 }
 uint32_t
 FloatRegister::getRegisterDumpOffsetInBytes()