[wasm-simd] Improve codegen for all_true and any_true

Based on feedback in https://github.com/WebAssembly/simd/issues/189 and
inspired by cranelift's codegen, we reduce instruction count by 1 for
both types of operations - all_true goes from 6 -> 5, any_true from 4 ->
3. The main transformation is to change a sequence of movq + ptest +
cmovq to ptest + setcc. We unfortunately cannot cut down the instruction
counts further, since we need to zero the destination register.

Change-Id: Idc2540dbec755c7a7ff5069955f74e978190161d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2100994Reviewed-by: Deepti Gandluri <gdeepti@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66710}

src/compiler/backend/x64/code-generator-x64.cc

@@ -587,18 +587,16 @@ void EmitWordLoadPoisoningIfNeeded(CodeGenerator* codegen,
     __ opcode(i.OutputSimd128Register(), i.InputSimd128Register(1), imm); \
   } while (false)
 
-#define ASSEMBLE_SIMD_ALL_TRUE(opcode)           \
-  do {                                           \
-    CpuFeatureScope sse_scope(tasm(), SSE4_1);   \
-    Register dst = i.OutputRegister();           \
-    Register tmp1 = i.TempRegister(0);           \
-    XMMRegister tmp2 = i.TempSimd128Register(1); \
-    __ movq(tmp1, Immediate(1));                 \
-    __ xorq(dst, dst);                           \
-    __ Pxor(tmp2, tmp2);                         \
-    __ opcode(tmp2, i.InputSimd128Register(0));  \
-    __ Ptest(tmp2, tmp2);                        \
-    __ cmovq(zero, dst, tmp1);                   \
+#define ASSEMBLE_SIMD_ALL_TRUE(opcode)          \
+  do {                                          \
+    CpuFeatureScope sse_scope(tasm(), SSE4_1);  \
+    Register dst = i.OutputRegister();          \
+    XMMRegister tmp = i.TempSimd128Register(0); \
+    __ xorq(dst, dst);                          \
+    __ Pxor(tmp, tmp);                          \
+    __ opcode(tmp, i.InputSimd128Register(0));  \
+    __ Ptest(tmp, tmp);                         \
+    __ setcc(equal, dst);                       \
   } while (false)
 
 // This macro will directly emit the opcode if the shift is an immediate - the
@@ -3922,11 +3920,10 @@ CodeGenerator::CodeGenResult CodeGenerator::AssembleArchInstruction(
       CpuFeatureScope sse_scope(tasm(), SSE4_1);
       Register dst = i.OutputRegister();
       XMMRegister src = i.InputSimd128Register(0);
-      Register tmp = i.TempRegister(0);
-      __ xorq(tmp, tmp);
-      __ movq(dst, Immediate(1));
-      __ ptest(src, src);
-      __ cmovq(zero, dst, tmp);
+
+      __ xorq(dst, dst);
+      __ Ptest(src, src);
+      __ setcc(not_equal, dst);
       break;
     }
     // Need to split up all the different lane structures because the

src/compiler/backend/x64/instruction-selector-x64.cc

@@ -2860,23 +2860,22 @@ SIMD_BINOP_ONE_TEMP_LIST(VISIT_SIMD_BINOP_ONE_TEMP)
 #undef VISIT_SIMD_BINOP_ONE_TEMP
 #undef SIMD_BINOP_ONE_TEMP_LIST
 
-#define VISIT_SIMD_ANYTRUE(Opcode)                                        \
-  void InstructionSelector::Visit##Opcode(Node* node) {                   \
-    X64OperandGenerator g(this);                                          \
-    InstructionOperand temps[] = {g.TempRegister()};                      \
-    Emit(kX64##Opcode, g.DefineAsRegister(node),                          \
-         g.UseUniqueRegister(node->InputAt(0)), arraysize(temps), temps); \
+#define VISIT_SIMD_ANYTRUE(Opcode)                      \
+  void InstructionSelector::Visit##Opcode(Node* node) { \
+    X64OperandGenerator g(this);                        \
+    Emit(kX64##Opcode, g.DefineAsRegister(node),        \
+         g.UseUniqueRegister(node->InputAt(0)));        \
   }
 SIMD_ANYTRUE_LIST(VISIT_SIMD_ANYTRUE)
 #undef VISIT_SIMD_ANYTRUE
 #undef SIMD_ANYTRUE_LIST
 
-#define VISIT_SIMD_ALLTRUE(Opcode)                                            \
-  void InstructionSelector::Visit##Opcode(Node* node) {                       \
-    X64OperandGenerator g(this);                                              \
-    InstructionOperand temps[] = {g.TempRegister(), g.TempSimd128Register()}; \
-    Emit(kX64##Opcode, g.DefineAsRegister(node),                              \
-         g.UseUniqueRegister(node->InputAt(0)), arraysize(temps), temps);     \
+#define VISIT_SIMD_ALLTRUE(Opcode)                                        \
+  void InstructionSelector::Visit##Opcode(Node* node) {                   \
+    X64OperandGenerator g(this);                                          \
+    InstructionOperand temps[] = {g.TempSimd128Register()};               \
+    Emit(kX64##Opcode, g.DefineAsRegister(node),                          \
+         g.UseUniqueRegister(node->InputAt(0)), arraysize(temps), temps); \
   }
 SIMD_ALLTRUE_LIST(VISIT_SIMD_ALLTRUE)
 #undef VISIT_SIMD_ALLTRUE