[llvm] [IPSCCP] Add range attribute handling. (PR #86747)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,82 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -passes=ipsccp -S | FileCheck %s
+
+declare void @use(i1)
+declare i32 @get_i32()
+
+define void @range_attribute(i32 range(i32 0, 10) %v) {
+; CHECK-LABEL: @range_attribute(
+; CHECK-NEXT:    call void @use(i1 true)
+; CHECK-NEXT:    [[C2:%.*]] = icmp ult i32 [[V:%.*]], 9
+; CHECK-NEXT:    call void @use(i1 [[C2]])
+; CHECK-NEXT:    call void @use(i1 false)
+; CHECK-NEXT:    [[C4:%.*]] = icmp ugt i32 [[V]], 8
+; CHECK-NEXT:    call void @use(i1 [[C4]])
+; CHECK-NEXT:    ret void
+;
+  %c1 = icmp ult i32 %v, 10
+  call void @use(i1 %c1)
+  %c2 = icmp ult i32 %v, 9
+  call void @use(i1 %c2)
+  %c3 = icmp ugt i32 %v, 9
+  call void @use(i1 %c3)
+  %c4 = icmp ugt i32 %v, 8
+  call void @use(i1 %c4)
+  ret void
+}
+
+define i32 @range_attribute_single(i32 range(i32 0, 1) %v) {
+; CHECK-LABEL: @range_attribute_single(
+; CHECK-NEXT:    ret i32 0
+;
+  ret i32 %v
+}
+
+define void @call_range_attribute(ptr %p) {
+; CHECK-LABEL: @call_range_attribute(
+; CHECK-NEXT:    [[V:%.*]] = call range(i32 0, 10) i32 @get_i32()
+; CHECK-NEXT:    call void @use(i1 true)
+; CHECK-NEXT:    [[C2:%.*]] = icmp ult i32 [[V]], 9
+; CHECK-NEXT:    call void @use(i1 [[C2]])
+; CHECK-NEXT:    call void @use(i1 false)
+; CHECK-NEXT:    [[C4:%.*]] = icmp ugt i32 [[V]], 8
+; CHECK-NEXT:    call void @use(i1 [[C4]])
+; CHECK-NEXT:    ret void
+;
+  %v = call range(i32 0, 10) i32 @get_i32()
+  %c1 = icmp ult i32 %v, 10
+  call void @use(i1 %c1)
+  %c2 = icmp ult i32 %v, 9
+  call void @use(i1 %c2)
+  %c3 = icmp ugt i32 %v, 9
+  call void @use(i1 %c3)
+  %c4 = icmp ugt i32 %v, 8
+  call void @use(i1 %c4)
+  ret void
+}
+
+
+declare range(i32 0, 10) i32 @get_i32_in_range()
+
+define void @call_range_result(ptr %p) {
+; CHECK-LABEL: @call_range_result(
+; CHECK-NEXT:    [[V:%.*]] = call i32 @get_i32_in_range()
+; CHECK-NEXT:    call void @use(i1 true)
+; CHECK-NEXT:    [[C2:%.*]] = icmp ult i32 [[V]], 9
+; CHECK-NEXT:    call void @use(i1 [[C2]])
+; CHECK-NEXT:    call void @use(i1 false)
+; CHECK-NEXT:    [[C4:%.*]] = icmp ugt i32 [[V]], 8
+; CHECK-NEXT:    call void @use(i1 [[C4]])
+; CHECK-NEXT:    ret void
+;
+  %v = call i32 @get_i32_in_range()
+  %c1 = icmp ult i32 %v, 10
+  call void @use(i1 %c1)
+  %c2 = icmp ult i32 %v, 9
+  call void @use(i1 %c2)
+  %c3 = icmp ugt i32 %v, 9
+  call void @use(i1 %c3)
+  %c4 = icmp ugt i32 %v, 8
+  call void @use(i1 %c4)
+  ret void
+}
----------------
nikic wrote:

This isn't quite what I was looking for, or maybe I'm misunderstanding the test. What I had in mind if a function with range(0, 10) that has icmp 5 and is only called with value 5, or something like that.

https://github.com/llvm/llvm-project/pull/86747