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| ; RUN: opt < %s -loop-reduce -S | FileCheck %s
target datalayout = "e-i64:64-v16:16-v32:32-n16:32:64"
; for (int i = 0; i < n; ++i) {
; use(i * 5 + 3);
; // i * a + b is ephemeral and shouldn't be promoted by LSR
; __builtin_assume(i * a + b >= 0);
; }
define void @ephemeral(i32 %a, i32 %b, i32 %n) {
; CHECK-LABEL: @ephemeral(
entry:
br label %loop
loop:
%i = phi i32 [ 0, %entry ], [ %inc, %loop ]
; Only i and i * 5 + 3 should be indvars, not i * a + b.
; CHECK: phi i32
; CHECK: phi i32
; CHECK-NOT: phi i32
%inc = add nsw i32 %i, 1
%exitcond = icmp eq i32 %inc, %n
%0 = mul nsw i32 %i, 5
%1 = add nsw i32 %0, 3
call void @use(i32 %1)
%2 = mul nsw i32 %i, %a
%3 = add nsw i32 %2, %b
%4 = icmp sgt i32 %3, -1
call void @llvm.assume(i1 %4)
br i1 %exitcond, label %exit, label %loop
exit:
ret void
}
declare void @use(i32)
declare void @llvm.assume(i1)
|