[spirv-reader] Add FDiv

Change-Id: Ie24bb91276340afd77009165af471ce0f53cca39
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/19503
Reviewed-by: dan sinclair <dsinclair@google.com>

src/reader/spirv/function.cc

@@ -46,6 +46,8 @@ ast::BinaryOp ConvertBinaryOp(SpvOp opcode) {
       return ast::BinaryOp::kSubtract;
     case SpvOpFMul:
       return ast::BinaryOp::kMultiply;
+    case SpvOpFDiv:
+      return ast::BinaryOp::kDivide;
     default:
       break;
   }

src/reader/spirv/function_arithmetic_test.cc

@@ -226,6 +226,19 @@ INSTANTIATE_TEST_SUITE_P(
                    "__vec_2__f32", AstFor("v2float_50_60"), "multiply",
                    AstFor("v2float_60_50")}));
 
+INSTANTIATE_TEST_SUITE_P(
+    SpvParserTest_FDiv,
+    SpvBinaryTest,
+    ::testing::Values(
+        // Scalar float
+        BinaryData{"float", "float_50", "OpFDiv", "float_60", "__f32",
+                   "ScalarConstructor{50.000000}", "divide",
+                   "ScalarConstructor{60.000000}"},
+        // Vector float
+        BinaryData{"v2float", "v2float_50_60", "OpFDiv", "v2float_60_50",
+                   "__vec_2__f32", AstFor("v2float_50_60"), "divide",
+                   AstFor("v2float_60_50")}));
+
 }  // namespace
 }  // namespace spirv
 }  // namespace reader