[llvm] [SPIR-V] Add llvm.loop.unroll metadata lowering (PR #132062)

[Dmitry Sidorov via llvm-commits]

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@@ -0,0 +1,228 @@
+; RUN: llc -mtriple=spirv-unknown-vulkan-compute -O0 -verify-machineinstrs %s -o - | FileCheck %s
+; RUN: %if spirv-tools %{ llc -O0 -mtriple=spirv-unknown-vulkan-compute %s -o - -filetype=obj | spirv-val %}
+
+; CHECK-DAG: OpName %[[#For:]] "for_loop"
+; CHECK-DAG: OpName %[[#While:]] "while_loop"
+; CHECK-DAG: OpName %[[#DoWhile:]] "do_while_loop"
+; CHECK-DAG: OpName %[[#Disable:]] "unroll_disable"
+; CHECK-DAG: OpName %[[#Count:]] "unroll_count"
+; CHECK-DAG: OpName %[[#Full:]] "unroll_full"
+; CHECK-DAG: OpName %[[#FullCount:]] "unroll_full_count"
+
+; CHECK: %[[#For]] = OpFunction
+; CHECK: OpLoopMerge %[[#]] %[[#]] Unroll
+
+; CHECK: %[[#While]] = OpFunction
+; CHECK: OpLoopMerge %[[#]] %[[#]] Unroll
+
+; CHECK: %[[#DoWhile]] = OpFunction
+; CHECK: OpLoopMerge %[[#]] %[[#]] Unroll
+
+; CHECK: %[[#Disable]] = OpFunction
+; CHECK: OpLoopMerge %[[#]] %[[#]] DontUnroll
+
+; CHECK: %[[#Count]] = OpFunction
+; CHECK: OpLoopMerge %[[#]] %[[#]] PartialCount 4
+
+; CHECK: %[[#Full]] = OpFunction
+; CHECK: OpLoopMerge %[[#]] %[[#]] Unroll|PartialCount 1
+
+; CHECK: %[[#FullCount]] = OpFunction
+; CHECK: OpLoopMerge %[[#]] %[[#]] Unroll|PartialCount 4
+
+define dso_local void @for_loop(ptr noundef %0, i32 noundef %1) {
+  %3 = alloca ptr, align 8
+  %4 = alloca i32, align 4
+  %5 = alloca i32, align 4
+  store ptr %0, ptr %3, align 8
+  store i32 %1, ptr %4, align 4
+  store i32 0, ptr %5, align 4
+  br label %6
+
+6:                                                ; preds = %15, %2
+  %7 = load i32, ptr %5, align 4
+  %8 = load i32, ptr %4, align 4
+  %9 = icmp slt i32 %7, %8
+  br i1 %9, label %10, label %18
+
+10:                                               ; preds = %6
+  %11 = load i32, ptr %5, align 4
+  %12 = load ptr, ptr %3, align 8
+  %13 = load i32, ptr %12, align 4
+  %14 = add nsw i32 %13, %11
+  store i32 %14, ptr %12, align 4
+  br label %15
+
+15:                                               ; preds = %10
+  %16 = load i32, ptr %5, align 4
+  %17 = add nsw i32 %16, 1
+  store i32 %17, ptr %5, align 4
+  br label %6, !llvm.loop !1
+
+18:                                               ; preds = %6
+  ret void
+}
+
+define dso_local void @while_loop(ptr noundef %0, i32 noundef %1) {
+  %3 = alloca ptr, align 8
+  %4 = alloca i32, align 4
+  %5 = alloca i32, align 4
+  store ptr %0, ptr %3, align 8
+  store i32 %1, ptr %4, align 4
+  store i32 0, ptr %5, align 4
+  br label %6
+
+6:                                                ; preds = %10, %2
+  %7 = load i32, ptr %5, align 4
+  %8 = load i32, ptr %4, align 4
+  %9 = icmp slt i32 %7, %8
+  br i1 %9, label %10, label %17
+
+10:                                               ; preds = %6
+  %11 = load i32, ptr %5, align 4
+  %12 = load ptr, ptr %3, align 8
+  %13 = load i32, ptr %12, align 4
+  %14 = add nsw i32 %13, %11
+  store i32 %14, ptr %12, align 4
+  %15 = load i32, ptr %5, align 4
+  %16 = add nsw i32 %15, 1
+  store i32 %16, ptr %5, align 4
+  br label %6, !llvm.loop !3
+
+17:                                               ; preds = %6
+  ret void
+}
+
+define dso_local void @do_while_loop(ptr noundef %0, i32 noundef %1) {
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MrSidims wrote:

For reference: this test case exposed an issue in reg2mem pass.

https://github.com/llvm/llvm-project/pull/132062