[llvm] [SPIRV] Add OpAccessChain instruction support (PR #66253)

[Nathan Gauër via llvm-commits]

================
@@ -0,0 +1,59 @@
+; RUN: llc -O0 -mtriple=spirv-unknown-unknown %s -o - | FileCheck %s
+
+; CHECK: [[uint:%[0-9]+]] = OpTypeInt 32 0
+
+%A = type {
+  i32,
+  i32
+}
+; CHECK:    [[A:%[0-9]+]] = OpTypeStruct [[uint]] [[uint]]
+
+%B = type {
+  %A,
+  i32,
+  %A
+}
+; CHECK:    [[B:%[0-9]+]] = OpTypeStruct [[A]] [[uint]] [[A]]
+
+; CHECK: [[uint_0:%[0-9]+]] = OpConstant [[uint]] 0
+; CHECK: [[uint_1:%[0-9]+]] = OpConstant [[uint]] 1
+; CHECK: [[uint_2:%[0-9]+]] = OpConstant [[uint]] 2
+
+; CHECK: [[ptr_uint:%[0-9]+]] = OpTypePointer Function [[uint]]
+; CHECK:    [[ptr_A:%[0-9]+]] = OpTypePointer Function [[A]]
+; CHECK:    [[ptr_B:%[0-9]+]] = OpTypePointer Function [[B]]
+
+define void @main() #1 {
+entry:
+  %0 = alloca %B, align 4
+; CHECK: [[tmp:%[0-9]+]] = OpVariable [[ptr_B]] Function
+
+  %1 = getelementptr %B, ptr %0, i32 0, i32 0
+; CHECK: {{%[0-9]+}} = OpAccessChain [[ptr_A]] [[tmp]] [[uint_0]]
+  %2 = getelementptr inbounds %B, ptr %0, i32 0, i32 0
+; CHECK: {{%[0-9]+}} = OpInBoundsAccessChain [[ptr_A]] [[tmp]] [[uint_0]]
+
+  %3 = getelementptr %B, ptr %0, i32 0, i32 1
+; CHECK: {{%[0-9]+}} = OpAccessChain [[ptr_uint]] [[tmp]] [[uint_1]]
+  %4 = getelementptr inbounds %B, ptr %0, i32 0, i32 1
+; CHECK: {{%[0-9]+}} = OpInBoundsAccessChain [[ptr_uint]] [[tmp]] [[uint_1]]
+
+  %5 = getelementptr %B, ptr %0, i32 0, i32 2
+; CHECK: {{%[0-9]+}} = OpAccessChain [[ptr_A]] [[tmp]] [[uint_2]]
+  %6 = getelementptr inbounds %B, ptr %0, i32 0, i32 2
+; CHECK: {{%[0-9]+}} = OpInBoundsAccessChain [[ptr_A]] [[tmp]] [[uint_2]]
+
+  %7 = getelementptr %B, ptr %0, i32 0, i32 2, i32 1
+; CHECK: {{%[0-9]+}} = OpAccessChain [[ptr_uint]] [[tmp]] [[uint_2]] [[uint_1]]
+  %8 = getelementptr inbounds %B, ptr %0, i32 0, i32 2, i32 1
+; CHECK: {{%[0-9]+}} = OpInBoundsAccessChain [[ptr_uint]] [[tmp]] [[uint_2]] [[uint_1]]
+
+  %9 = getelementptr %B, ptr %0, i32 0, i32 2
+	%10 = getelementptr %A, ptr %9, i32 0, i32 1
----------------
Keenuts wrote:

Arf this was a tab. Thanks!

https://github.com/llvm/llvm-project/pull/66253