1 files changed, 128 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/atomics/optimization-tests.js b/js/src/jit-test/tests/atomics/optimization-tests.js
new file mode 100644
index 000000000..7503219a3
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+++ b/js/src/jit-test/tests/atomics/optimization-tests.js
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+// Some optimization tests for the Atomics primitives.
+//
+// These do not test atomicity, just code generation on a single
+// thread.
+//
+// It's useful to look at the code generated for this test with -D to
+// the JS shell.
+//
+// Bug 1138348 - unconstrained use of byte registers on x64
+// Bug 1077014 - code generation for Atomic operations for effect,
+//               all platforms
+// Bug 1141121 - immediate operand in atomic operations on x86/x64
+
+if (!(this.Atomics && this.SharedArrayBuffer))
+    quit(0);
+
+var sum = 0;
+
+function f(ia, k) {
+    // For effect, variable value.  The generated code on x86/x64
+    // should be one LOCK ADDB.  (On ARM, there should be no
+    // sign-extend of the current value in the cell, otherwise this is
+    // still a LDREX/STREX loop.)
+    Atomics.add(ia, 0, k);
+
+    // Ditto constant value.  Here the LOCK ADDB should have an
+    // immediate operand.
+    Atomics.add(ia, 0, 1);
+}
+
+function f2(ia, k) {
+    // For effect, variable value and constant value.  The generated
+    // code on x86/x64 should be one LOCK SUBB.
+    Atomics.sub(ia, 2, k);
+
+    // Ditto constant value.  Here the LOCK SUBB should have an
+    // immediate operand.
+    Atomics.sub(ia, 2, 1);
+}
+
+function f4(ia, k) {
+    // For effect, variable value.  The generated code on x86/x64
+    // should be one LOCK ORB.  (On ARM, there should be no
+    // sign-extend of the current value in the cell, otherwise this is
+    // still a LDREX/STREX loop.)
+    Atomics.or(ia, 6, k);
+
+    // Ditto constant value.  Here the LOCK ORB should have an
+    // immediate operand.
+    Atomics.or(ia, 6, 1);
+}
+
+function g(ia, k) {
+    // For its value, variable value.  The generated code on x86/x64
+    // should be one LOCK XADDB.
+    sum += Atomics.add(ia, 1, k);
+
+    // Ditto constant value.  XADD does not admit an immediate
+    // operand, so in the second case there should be a preliminary
+    // MOV of the immediate to the output register.
+    sum += Atomics.add(ia, 1, 1);
+}
+
+function g2(ia, k) {
+    // For its value, variable value.  The generated code on x86/x64
+    // should be one LOCK XADDB, preceded by a NEG into the output
+    // register instead of a MOV.
+    sum += Atomics.sub(ia, 3, k);
+
+    // Ditto constant value.  XADD does not admit an immediate
+    // operand, so in the second case there should be a preliminary
+    // MOV of the negated immediate to the output register.
+    sum += Atomics.sub(ia, 3, 1);
+}
+
+function g4(ia, k) {
+    // For its value, variable value.  The generated code on x86/x64
+    // should be a loop around ORB ; CMPXCHGB
+    sum += Atomics.or(ia, 7, k);
+
+    // Ditto constant value.  Here the ORB in the loop should have
+    // an immediate operand.
+    sum += Atomics.or(ia, 7, 1);
+}
+
+function mod(stdlib, ffi, heap) {
+    "use asm";
+
+    var i8a = new stdlib.Int8Array(heap);
+    var add = stdlib.Atomics.add;
+    var sum = 0;
+
+    function f3(k) {
+	k = k|0;
+	add(i8a, 4, 1);
+	add(i8a, 4, k);
+    }
+
+    function g3(k) {
+	k = k|0;
+	sum = sum + add(i8a, 5, k)|0;
+	sum = sum + add(i8a, 5, 1)|0;
+    }
+
+    return {f3:f3, g3:g3};
+}
+
+var i8a = new Int8Array(new SharedArrayBuffer(65536));
+var { f3, g3 } = mod(this, {}, i8a.buffer);
+for ( var i=0 ; i < 10000 ; i++ ) {
+    f(i8a, i % 10);
+    g(i8a, i % 10);
+    f2(i8a, i % 10);
+    g2(i8a, i % 10);
+    f3(i % 10);
+    g3(i % 10);
+    f4(i8a, i % 10);
+    g4(i8a, i % 10);
+}
+
+assertEq(i8a[0], ((10000 + 10000*4.5) << 24) >> 24);
+assertEq(i8a[1], ((10000 + 10000*4.5) << 24) >> 24);
+assertEq(i8a[2], ((-10000 + -10000*4.5) << 24) >> 24);
+assertEq(i8a[3], ((-10000 + -10000*4.5) << 24) >> 24);
+assertEq(i8a[4], ((10000 + 10000*4.5) << 24) >> 24);
+assertEq(i8a[5], ((10000 + 10000*4.5) << 24) >> 24);
+assertEq(i8a[6], 15);
+assertEq(i8a[7], 15);