Implement bitwise complement operator

This translates to/from OpNot for SPIR-V, and ~ for all three textual
language backends.

Fixed: tint:866
Change-Id: Id934fb309221e3fca0e7efa33edaaae137fd8085
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/54980
Auto-Submit: James Price <jrprice@google.com>
Commit-Queue: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>

test/expressions/unary/complement.wgsl

@@ -0,0 +1,15 @@
+fn i(x : i32) -> i32 {
+  return ~x;
+}
+
+fn u(x : u32) -> u32 {
+  return ~x;
+}
+
+fn vi(x : vec4<i32>) -> vec4<i32> {
+  return ~x;
+}
+
+fn vu(x : vec4<u32>) -> vec4<u32> {
+  return ~x;
+}

test/expressions/unary/complement.wgsl.expected.hlsl

@@ -0,0 +1,20 @@
+[numthreads(1, 1, 1)]
+void unused_entry_point() {
+  return;
+}
+
+int i(int x) {
+  return ~(x);
+}
+
+uint u(uint x) {
+  return ~(x);
+}
+
+int4 vi(int4 x) {
+  return ~(x);
+}
+
+uint4 vu(uint4 x) {
+  return ~(x);
+}

test/expressions/unary/complement.wgsl.expected.msl

@@ -0,0 +1,19 @@
+#include <metal_stdlib>
+
+using namespace metal;
+int i(int x) {
+  return ~(x);
+}
+
+uint u(uint x) {
+  return ~(x);
+}
+
+int4 vi(int4 x) {
+  return ~(x);
+}
+
+uint4 vu(uint4 x) {
+  return ~(x);
+}
+

test/expressions/unary/complement.wgsl.expected.spvasm

@@ -0,0 +1,56 @@
+; SPIR-V
+; Version: 1.3
+; Generator: Google Tint Compiler; 0
+; Bound: 29
+; Schema: 0
+               OpCapability Shader
+               OpMemoryModel Logical GLSL450
+               OpEntryPoint GLCompute %unused_entry_point "unused_entry_point"
+               OpExecutionMode %unused_entry_point LocalSize 1 1 1
+               OpName %unused_entry_point "unused_entry_point"
+               OpName %i "i"
+               OpName %x "x"
+               OpName %u "u"
+               OpName %x_0 "x"
+               OpName %vi "vi"
+               OpName %x_1 "x"
+               OpName %vu "vu"
+               OpName %x_2 "x"
+       %void = OpTypeVoid
+          %1 = OpTypeFunction %void
+        %int = OpTypeInt 32 1
+          %5 = OpTypeFunction %int %int
+       %uint = OpTypeInt 32 0
+         %11 = OpTypeFunction %uint %uint
+      %v4int = OpTypeVector %int 4
+         %17 = OpTypeFunction %v4int %v4int
+     %v4uint = OpTypeVector %uint 4
+         %23 = OpTypeFunction %v4uint %v4uint
+%unused_entry_point = OpFunction %void None %1
+          %4 = OpLabel
+               OpReturn
+               OpFunctionEnd
+          %i = OpFunction %int None %5
+          %x = OpFunctionParameter %int
+          %9 = OpLabel
+         %10 = OpNot %int %x
+               OpReturnValue %10
+               OpFunctionEnd
+          %u = OpFunction %uint None %11
+        %x_0 = OpFunctionParameter %uint
+         %15 = OpLabel
+         %16 = OpNot %uint %x_0
+               OpReturnValue %16
+               OpFunctionEnd
+         %vi = OpFunction %v4int None %17
+        %x_1 = OpFunctionParameter %v4int
+         %21 = OpLabel
+         %22 = OpNot %v4int %x_1
+               OpReturnValue %22
+               OpFunctionEnd
+         %vu = OpFunction %v4uint None %23
+        %x_2 = OpFunctionParameter %v4uint
+         %27 = OpLabel
+         %28 = OpNot %v4uint %x_2
+               OpReturnValue %28
+               OpFunctionEnd

test/expressions/unary/complement.wgsl.expected.wgsl

@@ -0,0 +1,15 @@
+fn i(x : i32) -> i32 {
+  return ~(x);
+}
+
+fn u(x : u32) -> u32 {
+  return ~(x);
+}
+
+fn vi(x : vec4<i32>) -> vec4<i32> {
+  return ~(x);
+}
+
+fn vu(x : vec4<u32>) -> vec4<u32> {
+  return ~(x);
+}