Bug 1761850 - Fix wasm select on ARM64. r=jseward

JSOpToCondition is applicable only to integer types. JSOpToDoubleCondition and
ConditionFromDoubleCondition sequence has to be used for float types.

Differential Revision: https://phabricator.services.mozilla.com/D142288

js/src/jit-test/tests/wasm/binop-arm64-ion-codegen.js

@@ -300,7 +300,7 @@ codegenTestARM64_adhoc(
     'f',
     `9e6703e0  fmov    d0, xzr
      1e622000  fcmp    d0, d2
-     1e63bc20  fcsel   d0, d1, d3, lt`)
+     1e633c20  fcsel   d0, d1, d3, lo`)
 
 // FP ABS should not tie its input to its output.
 

js/src/jit-test/tests/wasm/regress/bug1761850.js

@@ -0,0 +1,96 @@
+// Testing runtime execution of select + comparison operations.
+// Normally they are folded into shorter/faster sequence than select alone.
+
+function cross(xs) {
+    let results = [];
+    for ( let x of xs )
+        for ( let y of xs )
+            results.push([x,y]);
+    return results;
+}
+
+const floatOps = {
+    lt(a, b) { return a < b ? 0 : 1; },
+    le(a, b) { return a <= b ? 0 : 1; },
+    gt(a, b) { return a > b ? 0 : 1; },
+    ge(a, b) { return a >= b ? 0 : 1; },
+    eq(a, b) { return a === b ? 0 : 1; },
+    ne(a, b) { return a !== b ? 0 : 1; },
+}
+
+for (let ty of ['f32', 'f64']) {
+    for (let op of ['lt', 'le', 'gt', 'ge', 'eq', 'ne']) {
+        const module = new WebAssembly.Module(wasmTextToBinary(`(module
+            (memory (export "memory") 1 1)
+            (func (export "test") (result i32)
+                i32.const 128
+                i32.load8_u
+                i32.const 129
+                i32.load8_u
+                i32.const 0
+                ${ty}.load
+                i32.const ${ty == 'f32' ? 4 : 8}
+                ${ty}.load
+                ${ty}.${op}
+                select
+            )
+            (data (i32.const 128) "\\00\\01"))`));
+        const instance = new WebAssembly.Instance(module);
+        const arr = new (ty == 'f32' ? Float32Array : Float64Array)(instance.exports.memory.buffer);
+        for (let [a, b] of cross(
+            [0, 1, -1e100, Infinity, -Infinity, 1e100, -1e-10, 1/-Infinity, NaN]
+        )) {
+            arr[0] = a; arr[1] = b;
+            assertEq(instance.exports.test(), floatOps[op](arr[0], arr[1]))
+        }
+    }
+}
+
+const intOps = {
+    lt(a, b) { return a < b ? 0 : 1; },
+    le(a, b) { return a <= b ? 0 : 1; },
+    gt(a, b) { return a > b ? 0 : 1; },
+    ge(a, b) { return a >= b ? 0 : 1; },
+    eq(a, b) { return a === b ? 0 : 1; },
+    ne(a, b) { return a !== b ? 0 : 1; },
+}
+
+for (let [ty, signed] of [['i32', true], ['i32', false], ['i64', true], ['i64', false]]) {
+    for (let op of ['lt', 'le', 'gt', 'ge', 'eq', 'ne']) {
+        const module = new WebAssembly.Module(wasmTextToBinary(`(module
+            (memory (export "memory") 1 1)
+            (func (export "test") (result i32)
+                i32.const 128
+                i32.load8_u
+                i32.const 129
+                i32.load8_u
+                i32.const 0
+                ${ty}.load
+                i32.const ${ty == 'i32' ? 4 : 8}
+                ${ty}.load
+                ${ty}.${op}${op[0] == 'l' || op[0] == 'g' ? (signed ? '_s' : '_u') : ''}
+                select
+            )
+            (data (i32.const 128) "\\00\\01"))`));
+        const instance = new WebAssembly.Instance(module);
+        const arr = new (ty == 'i32' ? (signed ? Int32Array : Uint32Array) :
+                                       (signed ? BigInt64Array : BigUint64Array))
+                        (instance.exports.memory.buffer);
+        const c = ty == 'i32' ? (a => a|0) : BigInt;
+        for (let [a, b] of cross(
+            [c(0), ~c(0), c(1), ~c(1), c(1) << c(8), ~c(1) << c(12)]
+        )) {
+            arr[0] = a; arr[1] = b;
+            assertEq(instance.exports.test(), intOps[op](arr[0], arr[1]))
+        }
+    }
+}
+
+
+function cross(xs) {
+    let results = [];
+    for ( let x of xs )
+        for ( let y of xs )
+            results.push([x,y]);
+    return results;
+}

js/src/jit/arm64/CodeGenerator-arm64.cpp

@@ -2525,7 +2525,14 @@ void CodeGenerator::visitWasmCompareAndSelect(LWasmCompareAndSelect* ins) {
   }
 
   // Act on flag.
-  Assembler::Condition cond = JSOpToCondition(ins->compareType(), ins->jsop());
+  Assembler::Condition cond;
+  if (compTy == MCompare::Compare_Float32 ||
+      compTy == MCompare::Compare_Double) {
+    cond = Assembler::ConditionFromDoubleCondition(
+        JSOpToDoubleCondition(ins->jsop()));
+  } else {
+    cond = JSOpToCondition(compTy, ins->jsop());
+  }
   MIRType insTy = ins->mir()->type();
   if (insTy == MIRType::Int32 || insTy == MIRType::Int64) {
     Register destReg = ToRegister(ins->output());