[llvm] [FuncSpec] Consider literal constants of recursive functions (PR #111162)

[Alexandros Lamprineas via llvm-commits]

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@@ -108,6 +108,46 @@ define i32 @main(ptr %0, i32 %1) {
 ; CHECK-NEXT:    ret void
 ;
 ;
+; CHECK-LABEL: define internal void @func.specialized.3(
+; CHECK-SAME: ptr [[TMP0:%.*]], i32 [[TMP1:%.*]]) {
+; CHECK-NEXT:    [[TMP3:%.*]] = alloca i32, align 4
+; CHECK-NEXT:    store i32 [[TMP1]], ptr [[TMP3]], align 4
+; CHECK-NEXT:    [[TMP4:%.*]] = load i32, ptr [[TMP3]], align 4
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp slt i32 [[TMP4]], 1
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[BB12:.*]], label %[[BB6:.*]]
+; CHECK:       [[BB6]]:
+; CHECK-NEXT:    [[TMP7:%.*]] = load i32, ptr [[TMP3]], align 4
+; CHECK-NEXT:    [[TMP8:%.*]] = sext i32 [[TMP7]] to i64
+; CHECK-NEXT:    [[TMP9:%.*]] = getelementptr inbounds i32, ptr [[TMP0]], i64 [[TMP8]]
+; CHECK-NEXT:    call void @decrement(ptr [[TMP9]])
+; CHECK-NEXT:    [[TMP10:%.*]] = load i32, ptr [[TMP3]], align 4
+; CHECK-NEXT:    [[TMP11:%.*]] = add nsw i32 [[TMP10]], -1
+; CHECK-NEXT:    call void @func.specialized.3(ptr [[TMP0]], i32 [[TMP11]])
+; CHECK-NEXT:    br label %[[BB12]]
+; CHECK:       [[BB12]]:
+; CHECK-NEXT:    ret void
+;
+;
+; ONE-ITER-LABEL: define internal void @func(
+; ONE-ITER-SAME: ptr [[TMP0:%.*]], i32 [[TMP1:%.*]], ptr nocapture [[TMP2:%.*]]) {
+; ONE-ITER-NEXT:    [[TMP4:%.*]] = alloca i32, align 4
+; ONE-ITER-NEXT:    store i32 [[TMP1]], ptr [[TMP4]], align 4
+; ONE-ITER-NEXT:    [[TMP5:%.*]] = load i32, ptr [[TMP4]], align 4
+; ONE-ITER-NEXT:    [[TMP6:%.*]] = icmp slt i32 [[TMP5]], 1
+; ONE-ITER-NEXT:    br i1 [[TMP6]], label %[[BB13:.*]], label %[[BB7:.*]]
+; ONE-ITER:       [[BB7]]:
+; ONE-ITER-NEXT:    [[TMP8:%.*]] = load i32, ptr [[TMP4]], align 4
+; ONE-ITER-NEXT:    [[TMP9:%.*]] = sext i32 [[TMP8]] to i64
+; ONE-ITER-NEXT:    [[TMP10:%.*]] = getelementptr inbounds i32, ptr [[TMP0]], i64 [[TMP9]]
+; ONE-ITER-NEXT:    call void [[TMP2]](ptr [[TMP10]])
+; ONE-ITER-NEXT:    [[TMP11:%.*]] = load i32, ptr [[TMP4]], align 4
+; ONE-ITER-NEXT:    [[TMP12:%.*]] = add nsw i32 [[TMP11]], -1
+; ONE-ITER-NEXT:    call void @func(ptr [[TMP0]], i32 [[TMP12]], ptr [[TMP2]])
+; ONE-ITER-NEXT:    br label %[[BB13]]
+; ONE-ITER:       [[BB13]]:
+; ONE-ITER-NEXT:    ret void
+;
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labrinea wrote:

Oh I've realised you're not adding tests but changing the codegen of existing ones. That doesn't seem right, I'd change the RUN lines of this file to prevent specialization on literal constants.

https://github.com/llvm/llvm-project/pull/111162