Changeset 279441 in webkit

Timestamp:

Jun 30, 2021 4:36:34 PM (3 years ago)

Author:

mark.lam@apple.com

Message:

ARM64: Disable selection of BFI instruction variants by default.
​https://bugs.webkit.org/show_bug.cgi?id=227554
rdar://79978150

Reviewed by Saam Barati.

We suspect that this may have caused some hangs. Disabling while we investigate.

• b3/B3LowerToAir.cpp:
• b3/testb3_2.cpp:

(testInsertBitField32):
(testInsertBitField64):

• runtime/OptionsList.h:

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• b3/B3LowerToAir.cpp (modified) (3 diffs)
• b3/testb3_2.cpp (modified) (2 diffs)
• runtime/OptionsList.h (modified) (1 diff)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2021-06-30  Mark Lam  <mark.lam@apple.com>
+
+        ARM64: Disable selection of BFI instruction variants by default.
+        https://bugs.webkit.org/show_bug.cgi?id=227554
+        rdar://79978150
+
+        Reviewed by Saam Barati.
+
+        We suspect that this may have caused some hangs.  Disabling while we investigate.
+
+        * b3/B3LowerToAir.cpp:
+        * b3/testb3_2.cpp:
+        (testInsertBitField32):
+        (testInsertBitField64):
+        * runtime/OptionsList.h:
+
 2021-06-29  Joonghun Park  <jh718.park@samsung.com>
 

trunk/Source/JavaScriptCore/b3/B3LowerToAir.cpp

@@ -2765 +2765 @@
             // Where: mask = (1 << width) - 1
             auto tryAppendUBFX = [&] () -> bool {
+                if (!Options::useBFI())
+                    return false;
                 Air::Opcode opcode = opcodeForType(ExtractUnsignedBitfield32, ExtractUnsignedBitfield64, m_value->type());
                 if (!isValidForm(opcode, Arg::Tmp, Arg::Imm, Arg::Imm, Arg::Tmp)) 
@@ -2827 +2829 @@
             //        mask2 = ~(mask1 << lsb)
             auto tryAppendBFI = [&] (Value* left, Value* right) -> bool {
+                if (!Options::useBFI())
+                    return false;
                 Air::Opcode opcode = opcodeForType(InsertBitField32, InsertBitField64, m_value->type());
                 if (!isValidForm(opcode, Arg::Tmp, Arg::Imm, Arg::Imm, Arg::Tmp)) 
@@ -3031 +3035 @@
             // where: amount = datasize - width
             auto tryAppendSBFIZ = [&] () -> bool {
+                if (!Options::useBFI())
+                    return false;
                 Air::Opcode opcode = opcodeForType(InsertSignedBitfieldInZero32, InsertSignedBitfieldInZero64, m_value->type());
                 if (!isValidForm(opcode, Arg::Tmp, Arg::Imm, Arg::Imm, Arg::Tmp))

trunk/Source/JavaScriptCore/b3/testb3_2.cpp

@@ -3161 +3161 @@
 void testInsertBitField32()
 {
+    if (!JSC::Options::useBFI())
+        return;
     if (JSC::Options::defaultB3OptLevel() < 2)
         return;
@@ -3239 +3241 @@
 void testInsertBitField64()
 {
+    if (!JSC::Options::useBFI())
+        return;
     if (JSC::Options::defaultB3OptLevel() < 2)
         return;

trunk/Source/JavaScriptCore/runtime/OptionsList.h

@@ -549 +549 @@
     v(Bool, useDataIC, isARM64(), Normal, nullptr) \
     v(Bool, useDataICInOptimizingJIT, false, Normal, nullptr) \
+    v(Bool, useBFI, false, Normal, "Allow ARM64 instruction selection of BFI") \