; REQUIRES: asserts ; RUN: llc < %s -O3 -march=x86-64 -mcpu=core2 -stress-ivchain | FileCheck %s -check-prefix=X64 ; RUN: llc < %s -O3 -march=x86 -mcpu=core2 -stress-ivchain | FileCheck %s -check-prefix=X32 ; @sharedidx is an unrolled variant of this loop: ; for (unsigned long i = 0; i < len; i += s) { ; c[i] = a[i] + b[i]; ; } ; where 's' cannot be folded into the addressing mode. ; ; This is not quite profitable to chain. But with -stress-ivchain, we ; can form three address chains in place of the shared induction ; variable. ; X64: sharedidx: ; X64: %for.body.preheader ; X64-NOT: leal ({{.*}},4) ; X64: %for.body.1 ; X32: sharedidx: ; X32: %for.body.2 ; X32: add ; X32: add ; X32: add ; X32: add ; X32: add ; X32: %for.body.3 define void @sharedidx(i8* nocapture %a, i8* nocapture %b, i8* nocapture %c, i32 %s, i32 %len) nounwind ssp { entry: %cmp8 = icmp eq i32 %len, 0 br i1 %cmp8, label %for.end, label %for.body for.body: ; preds = %entry, %for.body.3 %i.09 = phi i32 [ %add5.3, %for.body.3 ], [ 0, %entry ] %arrayidx = getelementptr inbounds i8, i8* %a, i32 %i.09 %0 = load i8, i8* %arrayidx, align 1 %conv6 = zext i8 %0 to i32 %arrayidx1 = getelementptr inbounds i8, i8* %b, i32 %i.09 %1 = load i8, i8* %arrayidx1, align 1 %conv27 = zext i8 %1 to i32 %add = add nsw i32 %conv27, %conv6 %conv3 = trunc i32 %add to i8 %arrayidx4 = getelementptr inbounds i8, i8* %c, i32 %i.09 store i8 %conv3, i8* %arrayidx4, align 1 %add5 = add i32 %i.09, %s %cmp = icmp ult i32 %add5, %len br i1 %cmp, label %for.body.1, label %for.end for.end: ; preds = %for.body, %for.body.1, %for.body.2, %for.body.3, %entry ret void for.body.1: ; preds = %for.body %arrayidx.1 = getelementptr inbounds i8, i8* %a, i32 %add5 %2 = load i8, i8* %arrayidx.1, align 1 %conv6.1 = zext i8 %2 to i32 %arrayidx1.1 = getelementptr inbounds i8, i8* %b, i32 %add5 %3 = load i8, i8* %arrayidx1.1, align 1 %conv27.1 = zext i8 %3 to i32 %add.1 = add nsw i32 %conv27.1, %conv6.1 %conv3.1 = trunc i32 %add.1 to i8 %arrayidx4.1 = getelementptr inbounds i8, i8* %c, i32 %add5 store i8 %conv3.1, i8* %arrayidx4.1, align 1 %add5.1 = add i32 %add5, %s %cmp.1 = icmp ult i32 %add5.1, %len br i1 %cmp.1, label %for.body.2, label %for.end for.body.2: ; preds = %for.body.1 %arrayidx.2 = getelementptr inbounds i8, i8* %a, i32 %add5.1 %4 = load i8, i8* %arrayidx.2, align 1 %conv6.2 = zext i8 %4 to i32 %arrayidx1.2 = getelementptr inbounds i8, i8* %b, i32 %add5.1 %5 = load i8, i8* %arrayidx1.2, align 1 %conv27.2 = zext i8 %5 to i32 %add.2 = add nsw i32 %conv27.2, %conv6.2 %conv3.2 = trunc i32 %add.2 to i8 %arrayidx4.2 = getelementptr inbounds i8, i8* %c, i32 %add5.1 store i8 %conv3.2, i8* %arrayidx4.2, align 1 %add5.2 = add i32 %add5.1, %s %cmp.2 = icmp ult i32 %add5.2, %len br i1 %cmp.2, label %for.body.3, label %for.end for.body.3: ; preds = %for.body.2 %arrayidx.3 = getelementptr inbounds i8, i8* %a, i32 %add5.2 %6 = load i8, i8* %arrayidx.3, align 1 %conv6.3 = zext i8 %6 to i32 %arrayidx1.3 = getelementptr inbounds i8, i8* %b, i32 %add5.2 %7 = load i8, i8* %arrayidx1.3, align 1 %conv27.3 = zext i8 %7 to i32 %add.3 = add nsw i32 %conv27.3, %conv6.3 %conv3.3 = trunc i32 %add.3 to i8 %arrayidx4.3 = getelementptr inbounds i8, i8* %c, i32 %add5.2 store i8 %conv3.3, i8* %arrayidx4.3, align 1 %add5.3 = add i32 %add5.2, %s %cmp.3 = icmp ult i32 %add5.3, %len br i1 %cmp.3, label %for.body, label %for.end }