; RUN: llc < %s -march=avr | FileCheck %s ; This tests how LLVM handles IR which puts very high ; presure on the PTRREGS class for the register allocator. ; ; This causes a problem because we only have one small register ; class for loading and storing from pointers - 'PTRREGS'. ; One of these registers is also used for the frame pointer, meaning ; that we only ever have two registers available for these operations. ; ; There is an existing bug filed for this issue - PR14879. ; ; The specific failure: ; LLVM ERROR: ran out of registers during register allocation ; ; It has been assembled from the following c code: ; ; struct ss ; { ; int a; ; int b; ; int c; ; }; ; ; void loop(struct ss *x, struct ss **y, int z) ; { ; int i; ; for (i=0; i<z; ++i) ; { ; x->c += y[i]->b; ; } ; } %struct.ss = type { i16, i16, i16 } ; CHECK-LABEL: loop define void @loop(%struct.ss* %x, %struct.ss** %y, i16 %z) #0 { entry: %x.addr = alloca %struct.ss*, align 2 %y.addr = alloca %struct.ss**, align 2 %z.addr = alloca i16, align 2 %i = alloca i16, align 2 store %struct.ss* %x, %struct.ss** %x.addr, align 2 store %struct.ss** %y, %struct.ss*** %y.addr, align 2 store i16 %z, i16* %z.addr, align 2 store i16 0, i16* %i, align 2 br label %for.cond for.cond: ; preds = %for.inc, %entry %tmp = load i16, i16* %i, align 2 %tmp1 = load i16, i16* %z.addr, align 2 %cmp = icmp slt i16 %tmp, %tmp1 br i1 %cmp, label %for.body, label %for.end for.body: ; preds = %for.cond %tmp2 = load %struct.ss**, %struct.ss*** %y.addr, align 2 %tmp3 = load i16, i16* %i, align 2 %arrayidx = getelementptr inbounds %struct.ss*, %struct.ss** %tmp2, i16 %tmp3 %tmp4 = load %struct.ss*, %struct.ss** %arrayidx, align 2 %b = getelementptr inbounds %struct.ss, %struct.ss* %tmp4, i32 0, i32 1 %tmp5 = load i16, i16* %b, align 2 %tmp6 = load %struct.ss*, %struct.ss** %x.addr, align 2 %c = getelementptr inbounds %struct.ss, %struct.ss* %tmp6, i32 0, i32 2 %tmp7 = load i16, i16* %c, align 2 %add = add nsw i16 %tmp7, %tmp5 store i16 %add, i16* %c, align 2 br label %for.inc for.inc: ; preds = %for.body %tmp8 = load i16, i16* %i, align 2 %inc = add nsw i16 %tmp8, 1 store i16 %inc, i16* %i, align 2 br label %for.cond for.end: ; preds = %for.cond ret void }