tint/resolver: Allow texture 'offset' to be const-expr

This allows the value to be declared in a `const` expression, and to use arithmetic.

Fixed: tint:1636
Change-Id: Ie641a9d4183429c79c91605cd4df78f569be3579
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/105623
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Dan Sinclair <dsinclair@chromium.org>
Commit-Queue: Ben Clayton <bclayton@google.com>

test/tint/builtins/gen/var/textureGather/1f7f6b.wgsl

@@ -26,7 +26,8 @@
 // fn textureGather(texture: texture_depth_2d, sampler: sampler, coords: vec2<f32>, @const offset: vec2<i32>) -> vec4<f32>
 fn textureGather_1f7f6b() {
   var arg_2 = vec2<f32>();
-  var res: vec4<f32> = textureGather(arg_0, arg_1, arg_2, vec2<i32>());
+  const arg_3 = vec2<i32>();
+  var res: vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/1f7f6b.wgsl.expected.wgsl

@@ -4,7 +4,8 @@
 
 fn textureGather_1f7f6b() {
   var arg_2 = vec2<f32>();
-  var res : vec4<f32> = textureGather(arg_0, arg_1, arg_2, vec2<i32>());
+  const arg_3 = vec2<i32>();
+  var res : vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/22e930.wgsl

@@ -25,9 +25,10 @@
 
 // fn textureGather(@const component: i32, texture: texture_2d_array<f32>, sampler: sampler, coords: vec2<f32>, array_index: i32) -> vec4<f32>
 fn textureGather_22e930() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
   var arg_4 = 1;
-  var res: vec4<f32> = textureGather(1, arg_1, arg_2, arg_3, arg_4);
+  var res: vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/22e930.wgsl.expected.wgsl

@@ -3,9 +3,10 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_22e930() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
   var arg_4 = 1;
-  var res : vec4<f32> = textureGather(1, arg_1, arg_2, arg_3, arg_4);
+  var res : vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/2cc066.wgsl

@@ -25,9 +25,10 @@
 
 // fn textureGather(@const component: i32, texture: texture_2d_array<u32>, sampler: sampler, coords: vec2<f32>, array_index: i32) -> vec4<u32>
 fn textureGather_2cc066() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
   var arg_4 = 1;
-  var res: vec4<u32> = textureGather(1, arg_1, arg_2, arg_3, arg_4);
+  var res: vec4<u32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/2cc066.wgsl.expected.wgsl

@@ -3,9 +3,10 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_2cc066() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
   var arg_4 = 1;
-  var res : vec4<u32> = textureGather(1, arg_1, arg_2, arg_3, arg_4);
+  var res : vec4<u32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/32c4e8.wgsl

@@ -25,8 +25,9 @@
 
 // fn textureGather(@const component: i32, texture: texture_cube<f32>, sampler: sampler, coords: vec3<f32>) -> vec4<f32>
 fn textureGather_32c4e8() {
+  const arg_0 = 1;
   var arg_3 = vec3<f32>();
-  var res: vec4<f32> = textureGather(1, arg_1, arg_2, arg_3);
+  var res: vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/32c4e8.wgsl.expected.wgsl

@@ -3,8 +3,9 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_32c4e8() {
+  const arg_0 = 1;
   var arg_3 = vec3<f32>();
-  var res : vec4<f32> = textureGather(1, arg_1, arg_2, arg_3);
+  var res : vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/3b32cc.wgsl

@@ -25,8 +25,9 @@
 
 // fn textureGather(@const component: i32, texture: texture_cube<u32>, sampler: sampler, coords: vec3<f32>) -> vec4<u32>
 fn textureGather_3b32cc() {
+  const arg_0 = 1;
   var arg_3 = vec3<f32>();
-  var res: vec4<u32> = textureGather(1, arg_1, arg_2, arg_3);
+  var res: vec4<u32> = textureGather(arg_0, arg_1, arg_2, arg_3);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/3b32cc.wgsl.expected.wgsl

@@ -3,8 +3,9 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_3b32cc() {
+  const arg_0 = 1;
   var arg_3 = vec3<f32>();
-  var res : vec4<u32> = textureGather(1, arg_1, arg_2, arg_3);
+  var res : vec4<u32> = textureGather(arg_0, arg_1, arg_2, arg_3);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/49b07f.wgsl

@@ -25,8 +25,10 @@
 
 // fn textureGather(@const component: i32, texture: texture_2d<u32>, sampler: sampler, coords: vec2<f32>, @const offset: vec2<i32>) -> vec4<u32>
 fn textureGather_49b07f() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
-  var res: vec4<u32> = textureGather(1, arg_1, arg_2, arg_3, vec2<i32>());
+  const arg_4 = vec2<i32>();
+  var res: vec4<u32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/49b07f.wgsl.expected.wgsl

@@ -3,8 +3,10 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_49b07f() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
-  var res : vec4<u32> = textureGather(1, arg_1, arg_2, arg_3, vec2<i32>());
+  const arg_4 = vec2<i32>();
+  var res : vec4<u32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/4b8103.wgsl

@@ -25,9 +25,11 @@
 
 // fn textureGather(@const component: i32, texture: texture_2d_array<f32>, sampler: sampler, coords: vec2<f32>, array_index: i32, @const offset: vec2<i32>) -> vec4<f32>
 fn textureGather_4b8103() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
   var arg_4 = 1;
-  var res: vec4<f32> = textureGather(1, arg_1, arg_2, arg_3, arg_4, vec2<i32>());
+  const arg_5 = vec2<i32>();
+  var res: vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4, arg_5);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/4b8103.wgsl.expected.wgsl

@@ -3,9 +3,11 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_4b8103() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
   var arg_4 = 1;
-  var res : vec4<f32> = textureGather(1, arg_1, arg_2, arg_3, arg_4, vec2<i32>());
+  const arg_5 = vec2<i32>();
+  var res : vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4, arg_5);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/5266da.wgsl

@@ -25,8 +25,9 @@
 
 // fn textureGather(@const component: i32, texture: texture_2d<f32>, sampler: sampler, coords: vec2<f32>) -> vec4<f32>
 fn textureGather_5266da() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
-  var res: vec4<f32> = textureGather(1, arg_1, arg_2, arg_3);
+  var res: vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/5266da.wgsl.expected.wgsl

@@ -3,8 +3,9 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_5266da() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
-  var res : vec4<f32> = textureGather(1, arg_1, arg_2, arg_3);
+  var res : vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/5ba85f.wgsl

@@ -25,8 +25,9 @@
 
 // fn textureGather(@const component: i32, texture: texture_cube<i32>, sampler: sampler, coords: vec3<f32>) -> vec4<i32>
 fn textureGather_5ba85f() {
+  const arg_0 = 1;
   var arg_3 = vec3<f32>();
-  var res: vec4<i32> = textureGather(1, arg_1, arg_2, arg_3);
+  var res: vec4<i32> = textureGather(arg_0, arg_1, arg_2, arg_3);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/5ba85f.wgsl.expected.wgsl

@@ -3,8 +3,9 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_5ba85f() {
+  const arg_0 = 1;
   var arg_3 = vec3<f32>();
-  var res : vec4<i32> = textureGather(1, arg_1, arg_2, arg_3);
+  var res : vec4<i32> = textureGather(arg_0, arg_1, arg_2, arg_3);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/5bd491.wgsl

@@ -25,8 +25,9 @@
 
 // fn textureGather(@const component: i32, texture: texture_2d<u32>, sampler: sampler, coords: vec2<f32>) -> vec4<u32>
 fn textureGather_5bd491() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
-  var res: vec4<u32> = textureGather(1, arg_1, arg_2, arg_3);
+  var res: vec4<u32> = textureGather(arg_0, arg_1, arg_2, arg_3);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/5bd491.wgsl.expected.wgsl

@@ -3,8 +3,9 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_5bd491() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
-  var res : vec4<u32> = textureGather(1, arg_1, arg_2, arg_3);
+  var res : vec4<u32> = textureGather(arg_0, arg_1, arg_2, arg_3);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/751f8a.wgsl

@@ -25,9 +25,10 @@
 
 // fn textureGather(@const component: i32, texture: texture_cube_array<f32>, sampler: sampler, coords: vec3<f32>, array_index: i32) -> vec4<f32>
 fn textureGather_751f8a() {
+  const arg_0 = 1;
   var arg_3 = vec3<f32>();
   var arg_4 = 1;
-  var res: vec4<f32> = textureGather(1, arg_1, arg_2, arg_3, arg_4);
+  var res: vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/751f8a.wgsl.expected.wgsl

@@ -3,9 +3,10 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_751f8a() {
+  const arg_0 = 1;
   var arg_3 = vec3<f32>();
   var arg_4 = 1;
-  var res : vec4<f32> = textureGather(1, arg_1, arg_2, arg_3, arg_4);
+  var res : vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/7c3828.wgsl

@@ -25,8 +25,10 @@
 
 // fn textureGather(@const component: i32, texture: texture_2d<i32>, sampler: sampler, coords: vec2<f32>, @const offset: vec2<i32>) -> vec4<i32>
 fn textureGather_7c3828() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
-  var res: vec4<i32> = textureGather(1, arg_1, arg_2, arg_3, vec2<i32>());
+  const arg_4 = vec2<i32>();
+  var res: vec4<i32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/7c3828.wgsl.expected.wgsl

@@ -3,8 +3,10 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_7c3828() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
-  var res : vec4<i32> = textureGather(1, arg_1, arg_2, arg_3, vec2<i32>());
+  const arg_4 = vec2<i32>();
+  var res : vec4<i32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/8b754c.wgsl

@@ -25,9 +25,10 @@
 
 // fn textureGather(@const component: i32, texture: texture_2d_array<i32>, sampler: sampler, coords: vec2<f32>, array_index: i32) -> vec4<i32>
 fn textureGather_8b754c() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
   var arg_4 = 1;
-  var res: vec4<i32> = textureGather(1, arg_1, arg_2, arg_3, arg_4);
+  var res: vec4<i32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/8b754c.wgsl.expected.wgsl

@@ -3,9 +3,10 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_8b754c() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
   var arg_4 = 1;
-  var res : vec4<i32> = textureGather(1, arg_1, arg_2, arg_3, arg_4);
+  var res : vec4<i32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/af55b3.wgsl

@@ -25,8 +25,10 @@
 
 // fn textureGather(@const component: i32, texture: texture_2d<f32>, sampler: sampler, coords: vec2<f32>, @const offset: vec2<i32>) -> vec4<f32>
 fn textureGather_af55b3() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
-  var res: vec4<f32> = textureGather(1, arg_1, arg_2, arg_3, vec2<i32>());
+  const arg_4 = vec2<i32>();
+  var res: vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/af55b3.wgsl.expected.wgsl

@@ -3,8 +3,10 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_af55b3() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
-  var res : vec4<f32> = textureGather(1, arg_1, arg_2, arg_3, vec2<i32>());
+  const arg_4 = vec2<i32>();
+  var res : vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/bb3ac5.wgsl

@@ -25,8 +25,9 @@
 
 // fn textureGather(@const component: i32, texture: texture_2d<i32>, sampler: sampler, coords: vec2<f32>) -> vec4<i32>
 fn textureGather_bb3ac5() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
-  var res: vec4<i32> = textureGather(1, arg_1, arg_2, arg_3);
+  var res: vec4<i32> = textureGather(arg_0, arg_1, arg_2, arg_3);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/bb3ac5.wgsl.expected.wgsl

@@ -3,8 +3,9 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_bb3ac5() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
-  var res : vec4<i32> = textureGather(1, arg_1, arg_2, arg_3);
+  var res : vec4<i32> = textureGather(arg_0, arg_1, arg_2, arg_3);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/c0640c.wgsl

@@ -25,9 +25,10 @@
 
 // fn textureGather(@const component: i32, texture: texture_cube_array<i32>, sampler: sampler, coords: vec3<f32>, array_index: i32) -> vec4<i32>
 fn textureGather_c0640c() {
+  const arg_0 = 1;
   var arg_3 = vec3<f32>();
   var arg_4 = 1;
-  var res: vec4<i32> = textureGather(1, arg_1, arg_2, arg_3, arg_4);
+  var res: vec4<i32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/c0640c.wgsl.expected.wgsl

@@ -3,9 +3,10 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_c0640c() {
+  const arg_0 = 1;
   var arg_3 = vec3<f32>();
   var arg_4 = 1;
-  var res : vec4<i32> = textureGather(1, arg_1, arg_2, arg_3, arg_4);
+  var res : vec4<i32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/d1f187.wgsl

@@ -25,9 +25,11 @@
 
 // fn textureGather(@const component: i32, texture: texture_2d_array<u32>, sampler: sampler, coords: vec2<f32>, array_index: i32, @const offset: vec2<i32>) -> vec4<u32>
 fn textureGather_d1f187() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
   var arg_4 = 1;
-  var res: vec4<u32> = textureGather(1, arg_1, arg_2, arg_3, arg_4, vec2<i32>());
+  const arg_5 = vec2<i32>();
+  var res: vec4<u32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4, arg_5);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/d1f187.wgsl.expected.wgsl

@@ -3,9 +3,11 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_d1f187() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
   var arg_4 = 1;
-  var res : vec4<u32> = textureGather(1, arg_1, arg_2, arg_3, arg_4, vec2<i32>());
+  const arg_5 = vec2<i32>();
+  var res : vec4<u32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4, arg_5);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/d90605.wgsl

@@ -27,7 +27,8 @@
 fn textureGather_d90605() {
   var arg_2 = vec2<f32>();
   var arg_3 = 1;
-  var res: vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3, vec2<i32>());
+  const arg_4 = vec2<i32>();
+  var res: vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/d90605.wgsl.expected.wgsl

@@ -5,7 +5,8 @@
 fn textureGather_d90605() {
   var arg_2 = vec2<f32>();
   var arg_3 = 1;
-  var res : vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3, vec2<i32>());
+  const arg_4 = vec2<i32>();
+  var res : vec4<f32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/e9d390.wgsl

@@ -25,9 +25,11 @@
 
 // fn textureGather(@const component: i32, texture: texture_2d_array<i32>, sampler: sampler, coords: vec2<f32>, array_index: i32, @const offset: vec2<i32>) -> vec4<i32>
 fn textureGather_e9d390() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
   var arg_4 = 1;
-  var res: vec4<i32> = textureGather(1, arg_1, arg_2, arg_3, arg_4, vec2<i32>());
+  const arg_5 = vec2<i32>();
+  var res: vec4<i32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4, arg_5);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/e9d390.wgsl.expected.wgsl

@@ -3,9 +3,11 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_e9d390() {
+  const arg_0 = 1;
   var arg_3 = vec2<f32>();
   var arg_4 = 1;
-  var res : vec4<i32> = textureGather(1, arg_1, arg_2, arg_3, arg_4, vec2<i32>());
+  const arg_5 = vec2<i32>();
+  var res : vec4<i32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4, arg_5);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/f2c6e3.wgsl

@@ -25,9 +25,10 @@
 
 // fn textureGather(@const component: i32, texture: texture_cube_array<u32>, sampler: sampler, coords: vec3<f32>, array_index: i32) -> vec4<u32>
 fn textureGather_f2c6e3() {
+  const arg_0 = 1;
   var arg_3 = vec3<f32>();
   var arg_4 = 1;
-  var res: vec4<u32> = textureGather(1, arg_1, arg_2, arg_3, arg_4);
+  var res: vec4<u32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex

test/tint/builtins/gen/var/textureGather/f2c6e3.wgsl.expected.wgsl

@@ -3,9 +3,10 @@
 @group(1) @binding(2) var arg_2 : sampler;
 
 fn textureGather_f2c6e3() {
+  const arg_0 = 1;
   var arg_3 = vec3<f32>();
   var arg_4 = 1;
-  var res : vec4<u32> = textureGather(1, arg_1, arg_2, arg_3, arg_4);
+  var res : vec4<u32> = textureGather(arg_0, arg_1, arg_2, arg_3, arg_4);
 }
 
 @vertex