; RUN: opt < %s -S -analyze -scalar-evolution | FileCheck %s ; ScalarEvolution should be able to fold away the sign-extensions ; on this loop with a primary induction variable incremented with ; a nsw add of 2 (this test is derived from the nsw-offset.ll test, but uses an ; assume instead of a preheader conditional branch to guard the loop). target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128" define void @foo(i32 %no, double* nocapture %d, double* nocapture %q) nounwind { entry: %n = and i32 %no, 4294967294 %0 = icmp sgt i32 %n, 0 ; <i1> [#uses=1] tail call void @llvm.assume(i1 %0) br label %bb.nph bb.nph: ; preds = %entry br label %bb bb: ; preds = %bb.nph, %bb1 %i.01 = phi i32 [ %16, %bb1 ], [ 0, %bb.nph ] ; <i32> [#uses=5] ; CHECK: %1 = sext i32 %i.01 to i64 ; CHECK: --> {0,+,2}<nuw><nsw><%bb> %1 = sext i32 %i.01 to i64 ; <i64> [#uses=1] ; CHECK: %2 = getelementptr inbounds double, double* %d, i64 %1 ; CHECK: --> {%d,+,16}<nsw><%bb> %2 = getelementptr inbounds double, double* %d, i64 %1 ; <double*> [#uses=1] %3 = load double, double* %2, align 8 ; <double> [#uses=1] %4 = sext i32 %i.01 to i64 ; <i64> [#uses=1] %5 = getelementptr inbounds double, double* %q, i64 %4 ; <double*> [#uses=1] %6 = load double, double* %5, align 8 ; <double> [#uses=1] %7 = or i32 %i.01, 1 ; <i32> [#uses=1] ; CHECK: %8 = sext i32 %7 to i64 ; CHECK: --> {1,+,2}<nuw><nsw><%bb> %8 = sext i32 %7 to i64 ; <i64> [#uses=1] ; CHECK: %9 = getelementptr inbounds double, double* %q, i64 %8 ; CHECK: {(8 + %q)<nsw>,+,16}<nsw><%bb> %9 = getelementptr inbounds double, double* %q, i64 %8 ; <double*> [#uses=1] ; Artificially repeat the above three instructions, this time using ; add nsw instead of or. %t7 = add nsw i32 %i.01, 1 ; <i32> [#uses=1] ; CHECK: %t8 = sext i32 %t7 to i64 ; CHECK: --> {1,+,2}<nuw><nsw><%bb> %t8 = sext i32 %t7 to i64 ; <i64> [#uses=1] ; CHECK: %t9 = getelementptr inbounds double, double* %q, i64 %t8 ; CHECK: {(8 + %q)<nsw>,+,16}<nsw><%bb> %t9 = getelementptr inbounds double, double* %q, i64 %t8 ; <double*> [#uses=1] %10 = load double, double* %9, align 8 ; <double> [#uses=1] %11 = fadd double %6, %10 ; <double> [#uses=1] %12 = fadd double %11, 3.200000e+00 ; <double> [#uses=1] %13 = fmul double %3, %12 ; <double> [#uses=1] %14 = sext i32 %i.01 to i64 ; <i64> [#uses=1] %15 = getelementptr inbounds double, double* %d, i64 %14 ; <double*> [#uses=1] store double %13, double* %15, align 8 %16 = add nsw i32 %i.01, 2 ; <i32> [#uses=2] br label %bb1 bb1: ; preds = %bb %17 = icmp slt i32 %16, %n ; <i1> [#uses=1] br i1 %17, label %bb, label %bb1.return_crit_edge bb1.return_crit_edge: ; preds = %bb1 br label %return return: ; preds = %bb1.return_crit_edge, %entry ret void } declare void @llvm.assume(i1) nounwind ; Note: Without the preheader assume, there is an 'smax' in the ; backedge-taken count expression: ; CHECK: Loop %bb: backedge-taken count is ((-1 + (2 * (%no /u 2))) /u 2) ; CHECK: Loop %bb: max backedge-taken count is 1073741822