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; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py
; RUN: opt < %s -disable-output "-passes=print<scalar-evolution>" 2>&1 | FileCheck %s
; RUN: opt < %s -disable-output "-passes=print<scalar-evolution>" -scev-range-iter-threshold=1 2>&1 | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64"
; Collection of cases exercising range logic, mostly (but not exclusively)
; involving SCEVUnknowns.
declare void @llvm.assume(i1)
define i32 @ashr(i32 %a) {
; CHECK-LABEL: 'ashr'
; CHECK-NEXT: Classifying expressions for: @ashr
; CHECK-NEXT: %ashr = ashr i32 %a, 31
; CHECK-NEXT: --> %ashr U: [0,1) S: [0,1)
; CHECK-NEXT: Determining loop execution counts for: @ashr
;
%ashr = ashr i32 %a, 31
%pos = icmp sge i32 %a, 0
call void @llvm.assume(i1 %pos)
ret i32 %ashr
}
; Highlight the fact that non-argument non-instructions are
; also possible.
@G = external global i8
define i64 @ashr_global() {
; CHECK-LABEL: 'ashr_global'
; CHECK-NEXT: Classifying expressions for: @ashr_global
; CHECK-NEXT: %ashr = ashr i64 ptrtoint (ptr @G to i64), 63
; CHECK-NEXT: --> %ashr U: [-1,1) S: [-1,1)
; CHECK-NEXT: Determining loop execution counts for: @ashr_global
;
%ashr = ashr i64 ptrtoint (ptr @G to i64), 63
%pos = icmp sge ptr @G, null
call void @llvm.assume(i1 %pos)
ret i64 %ashr
}
define i32 @shl(i32 %a) {
; CHECK-LABEL: 'shl'
; CHECK-NEXT: Classifying expressions for: @shl
; CHECK-NEXT: %res = shl i32 %a, 2
; CHECK-NEXT: --> (4 * %a) U: [0,-3) S: [-2147483648,2147483645)
; CHECK-NEXT: Determining loop execution counts for: @shl
;
%res = shl i32 %a, 2
%pos = icmp ult i32 %a, 1024
call void @llvm.assume(i1 %pos)
ret i32 %res
}
define i32 @lshr(i32 %a) {
; CHECK-LABEL: 'lshr'
; CHECK-NEXT: Classifying expressions for: @lshr
; CHECK-NEXT: %res = lshr i32 %a, 31
; CHECK-NEXT: --> (%a /u -2147483648) U: [0,2) S: [0,2)
; CHECK-NEXT: Determining loop execution counts for: @lshr
;
%res = lshr i32 %a, 31
%pos = icmp sge i32 %a, 0
call void @llvm.assume(i1 %pos)
ret i32 %res
}
define i32 @udiv(i32 %a) {
; CHECK-LABEL: 'udiv'
; CHECK-NEXT: Classifying expressions for: @udiv
; CHECK-NEXT: %res = udiv i32 %a, -2147483648
; CHECK-NEXT: --> (%a /u -2147483648) U: [0,2) S: [0,2)
; CHECK-NEXT: Determining loop execution counts for: @udiv
;
%res = udiv i32 %a, 2147483648
%pos = icmp sge i32 %a, 0
call void @llvm.assume(i1 %pos)
ret i32 %res
}
define i64 @sext(i8 %a) {
; CHECK-LABEL: 'sext'
; CHECK-NEXT: Classifying expressions for: @sext
; CHECK-NEXT: %res = sext i8 %a to i64
; CHECK-NEXT: --> (sext i8 %a to i64) U: [-128,128) S: [-128,128)
; CHECK-NEXT: Determining loop execution counts for: @sext
;
%res = sext i8 %a to i64
%pos = icmp sge i8 %a, 0
call void @llvm.assume(i1 %pos)
ret i64 %res
}
define i64 @zext(i8 %a) {
; CHECK-LABEL: 'zext'
; CHECK-NEXT: Classifying expressions for: @zext
; CHECK-NEXT: %res = zext i8 %a to i64
; CHECK-NEXT: --> (zext i8 %a to i64) U: [0,256) S: [0,256)
; CHECK-NEXT: Determining loop execution counts for: @zext
;
%res = zext i8 %a to i64
%pos = icmp sge i8 %a, 0
call void @llvm.assume(i1 %pos)
ret i64 %res
}
define i32 @phi_div() {
; CHECK-LABEL: 'phi_div'
; CHECK-NEXT: Classifying expressions for: @phi_div
; CHECK-NEXT: %range.1 = phi i32 [ 0, %entry ], [ %shr, %loop ]
; CHECK-NEXT: --> %range.1 U: [0,1) S: [0,1) Exits: <<Unknown>> LoopDispositions: { %loop: Variant }
; CHECK-NEXT: %shr = lshr i32 %range.1, 1
; CHECK-NEXT: --> (%range.1 /u 2) U: [0,1) S: [0,1) Exits: <<Unknown>> LoopDispositions: { %loop: Variant }
; CHECK-NEXT: Determining loop execution counts for: @phi_div
; CHECK-NEXT: Loop %loop: <multiple exits> Unpredictable backedge-taken count.
; CHECK-NEXT: Loop %loop: Unpredictable constant max backedge-taken count.
; CHECK-NEXT: Loop %loop: Unpredictable symbolic max backedge-taken count.
; CHECK-NEXT: Loop %loop: Unpredictable predicated backedge-taken count.
;
entry:
br label %loop
loop:
%range.1 = phi i32 [ 0, %entry ], [ %shr, %loop ]
%shr = lshr i32 %range.1, 1
br label %loop
}
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