[clang] [lld] [llvm] [IR] Change representation of getelementptr inrange (PR #84341)

[Nicolai Hähnle via cfe-commits]

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@@ -23,24 +23,26 @@
 @PR23753_b = global ptr getelementptr (i8, ptr @PR23753_a, i64 ptrtoint (ptr @PR23753_a to i64))
 ; CHECK: @PR23753_b = global ptr getelementptr (i8, ptr @PR23753_a, i64 ptrtoint (ptr @PR23753_a to i64))
 
-; Verify that inrange on an index inhibits over-indexed getelementptr folding.
+; Verify that inrange doesn't inhibit over-indexed getelementptr folding,
+; but does inhibit combining two GEPs where the inner one has inrange (this
+; will be done when DataLayout is available instead).
 
 @nestedarray = global [2 x [4 x ptr]] zeroinitializer
 
-; CHECK: @nestedarray.1 = alias ptr, getelementptr inbounds ([2 x [4 x ptr]], ptr @nestedarray, inrange i32 0, i64 1, i32 0)
- at nestedarray.1 = alias ptr, getelementptr inbounds ([2 x [4 x ptr]], ptr @nestedarray, inrange i32 0, i32 0, i32 4)
+; CHECK: @nestedarray.1 = alias ptr, getelementptr inbounds inrange(-32, 32) ([2 x [4 x ptr]], ptr @nestedarray, i32 0, i64 1, i32 0)
+ at nestedarray.1 = alias ptr, getelementptr inbounds inrange(-32, 32) ([2 x [4 x ptr]], ptr @nestedarray, i32 0, i32 0, i32 4)
 
-; CHECK: @nestedarray.2 = alias ptr, getelementptr inbounds ([2 x [4 x ptr]], ptr @nestedarray, i32 0, inrange i32 0, i32 4)
- at nestedarray.2 = alias ptr, getelementptr inbounds ([2 x [4 x ptr]], ptr @nestedarray, i32 0, inrange i32 0, i32 4)
+; CHECK: @nestedarray.2 = alias ptr, getelementptr inbounds inrange(0, 1) ([2 x [4 x ptr]], ptr @nestedarray, i32 0, i64 1, i32 0)
+ at nestedarray.2 = alias ptr, getelementptr inbounds inrange(0, 1) ([2 x [4 x ptr]], ptr @nestedarray, i32 0, i32 0, i32 4)
 
-; CHECK: @nestedarray.3 = alias ptr, getelementptr inbounds ([2 x [4 x ptr]], ptr @nestedarray, i32 0, inrange i32 0)
- at nestedarray.3 = alias ptr, getelementptr inbounds ([4 x ptr], ptr getelementptr inbounds ([2 x [4 x ptr]], ptr @nestedarray, i32 0, inrange i32 0), i32 0, i32 0)
+; CHECK: @nestedarray.3 = alias ptr, getelementptr inbounds inrange(0, 4) ([4 x ptr], ptr @nestedarray, i32 0, i32 0)
+ at nestedarray.3 = alias ptr, getelementptr inbounds inrange(0, 4) ([4 x ptr], ptr getelementptr inbounds ([2 x [4 x ptr]], ptr @nestedarray, i32 0, i32 0), i32 0, i32 0)
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nhaehnle wrote:

I never realized that we sometimes insert additional GEP expressions like that -- why? Is this just a left-over from typed pointer thinking that you intend to remove at some point?

https://github.com/llvm/llvm-project/pull/84341