1 files changed, 490 insertions, 0 deletions
diff --git a/llvm/test/CodeGen/SystemZ/int-usub-10.ll b/llvm/test/CodeGen/SystemZ/int-usub-10.ll
new file mode 100644
index 00000000000..97f08777894
--- /dev/null
+++ b/llvm/test/CodeGen/SystemZ/int-usub-10.ll
@@ -0,0 +1,490 @@
+; Test 32-bit subtractions of constants from memory.
+;
+; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s
+
+declare i32 @foo()
+
+; Check subtraction of 1.
+define zeroext i1 @f1(i32 *%ptr) {
+; CHECK-LABEL: f1:
+; CHECK: alsi 0(%r2), -1
+; CHECK: ipm [[REG:%r[0-5]]]
+; CHECK: afi [[REG]], -536870912
+; CHECK: risbg %r2, [[REG]], 63, 191, 33
+; CHECK: br %r14
+  %a = load i32, i32 *%ptr
+  %t = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 1)
+  %val = extractvalue {i32, i1} %t, 0
+  %obit = extractvalue {i32, i1} %t, 1
+  store i32 %val, i32 *%ptr
+  ret i1 %obit
+}
+
+; Check the high end of the constant range.
+define zeroext i1 @f2(i32 *%ptr) {
+; CHECK-LABEL: f2:
+; CHECK: alsi 0(%r2), -128
+; CHECK: ipm [[REG:%r[0-5]]]
+; CHECK: afi [[REG]], -536870912
+; CHECK: risbg %r2, [[REG]], 63, 191, 33
+; CHECK: br %r14
+  %a = load i32, i32 *%ptr
+  %t = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 128)
+  %val = extractvalue {i32, i1} %t, 0
+  %obit = extractvalue {i32, i1} %t, 1
+  store i32 %val, i32 *%ptr
+  ret i1 %obit
+}
+
+; Check the next constant up, which must use a subtraction and a store.
+define zeroext i1 @f3(i32 %dummy, i32 *%ptr) {
+; CHECK-LABEL: f3:
+; CHECK: l [[VAL:%r[0-5]]], 0(%r3)
+; CHECK: slfi [[VAL]], 129
+; CHECK-DAG: st [[VAL]], 0(%r3)
+; CHECK-DAG: ipm [[REG:%r[0-5]]]
+; CHECK-DAG: afi [[REG]], -536870912
+; CHECK-DAG: risbg %r2, [[REG]], 63, 191, 33
+; CHECK: br %r14
+  %a = load i32, i32 *%ptr
+  %t = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 129)
+  %val = extractvalue {i32, i1} %t, 0
+  %obit = extractvalue {i32, i1} %t, 1
+  store i32 %val, i32 *%ptr
+  ret i1 %obit
+}
+
+; Check the low end of the constant range.
+define zeroext i1 @f4(i32 *%ptr) {
+; CHECK-LABEL: f4:
+; CHECK: alsi 0(%r2), 127
+; CHECK: ipm [[REG:%r[0-5]]]
+; CHECK: afi [[REG]], -536870912
+; CHECK: risbg %r2, [[REG]], 63, 191, 33
+; CHECK: br %r14
+  %a = load i32, i32 *%ptr
+  %t = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 -127)
+  %val = extractvalue {i32, i1} %t, 0
+  %obit = extractvalue {i32, i1} %t, 1
+  store i32 %val, i32 *%ptr
+  ret i1 %obit
+}
+
+; Check the next value down, with the same comment as f3.
+define zeroext i1 @f5(i32 %dummy, i32 *%ptr) {
+; CHECK-LABEL: f5:
+; CHECK: l [[VAL:%r[0-5]]], 0(%r3)
+; CHECK: slfi [[VAL]], 4294967168
+; CHECK-DAG: st [[VAL]], 0(%r3)
+; CHECK-DAG: ipm [[REG:%r[0-5]]]
+; CHECK-DAG: afi [[REG]], -536870912
+; CHECK-DAG: risbg %r2, [[REG]], 63, 191, 33
+; CHECK: br %r14
+  %a = load i32, i32 *%ptr
+  %t = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 -128)
+  %val = extractvalue {i32, i1} %t, 0
+  %obit = extractvalue {i32, i1} %t, 1
+  store i32 %val, i32 *%ptr
+  ret i1 %obit
+}
+
+; Check the high end of the aligned ASI range.
+define zeroext i1 @f6(i32 *%base) {
+; CHECK-LABEL: f6:
+; CHECK: alsi 524284(%r2), -1
+; CHECK: ipm [[REG:%r[0-5]]]
+; CHECK: afi [[REG]], -536870912
+; CHECK: risbg %r2, [[REG]], 63, 191, 33
+; CHECK: br %r14
+  %ptr = getelementptr i32, i32 *%base, i64 131071
+  %a = load i32, i32 *%ptr
+  %t = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 1)
+  %val = extractvalue {i32, i1} %t, 0
+  %obit = extractvalue {i32, i1} %t, 1
+  store i32 %val, i32 *%ptr
+  ret i1 %obit
+}
+
+; Check the next word up, which must use separate address logic.
+; Other sequences besides this one would be OK.
+define zeroext i1 @f7(i32 *%base) {
+; CHECK-LABEL: f7:
+; CHECK: agfi %r2, 524288
+; CHECK: alsi 0(%r2), -1
+; CHECK: ipm [[REG:%r[0-5]]]
+; CHECK: afi [[REG]], -536870912
+; CHECK: risbg %r2, [[REG]], 63, 191, 33
+; CHECK: br %r14
+  %ptr = getelementptr i32, i32 *%base, i64 131072
+  %a = load i32, i32 *%ptr
+  %t = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 1)
+  %val = extractvalue {i32, i1} %t, 0
+  %obit = extractvalue {i32, i1} %t, 1
+  store i32 %val, i32 *%ptr
+  ret i1 %obit
+}
+
+; Check the low end of the ALSI range.
+define zeroext i1 @f8(i32 *%base) {
+; CHECK-LABEL: f8:
+; CHECK: alsi -524288(%r2), -1
+; CHECK: ipm [[REG:%r[0-5]]]
+; CHECK: afi [[REG]], -536870912
+; CHECK: risbg %r2, [[REG]], 63, 191, 33
+; CHECK: br %r14
+  %ptr = getelementptr i32, i32 *%base, i64 -131072
+  %a = load i32, i32 *%ptr
+  %t = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 1)
+  %val = extractvalue {i32, i1} %t, 0
+  %obit = extractvalue {i32, i1} %t, 1
+  store i32 %val, i32 *%ptr
+  ret i1 %obit
+}
+
+; Check the next word down, which must use separate address logic.
+; Other sequences besides this one would be OK.
+define zeroext i1 @f9(i32 *%base) {
+; CHECK-LABEL: f9:
+; CHECK: agfi %r2, -524292
+; CHECK: alsi 0(%r2), -1
+; CHECK: ipm [[REG:%r[0-5]]]
+; CHECK: afi [[REG]], -536870912
+; CHECK: risbg %r2, [[REG]], 63, 191, 33
+; CHECK: br %r14
+  %ptr = getelementptr i32, i32 *%base, i64 -131073
+  %a = load i32, i32 *%ptr
+  %t = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 1)
+  %val = extractvalue {i32, i1} %t, 0
+  %obit = extractvalue {i32, i1} %t, 1
+  store i32 %val, i32 *%ptr
+  ret i1 %obit
+}
+
+; Check that ALSI does not allow indices.
+define zeroext i1 @f10(i64 %base, i64 %index) {
+; CHECK-LABEL: f10:
+; CHECK: agr %r2, %r3
+; CHECK: alsi 4(%r2), -1
+; CHECK: ipm [[REG:%r[0-5]]]
+; CHECK: afi [[REG]], -536870912
+; CHECK: risbg %r2, [[REG]], 63, 191, 33
+; CHECK: br %r14
+  %add1 = add i64 %base, %index
+  %add2 = add i64 %add1, 4
+  %ptr = inttoptr i64 %add2 to i32 *
+  %a = load i32, i32 *%ptr
+  %t = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 1)
+  %val = extractvalue {i32, i1} %t, 0
+  %obit = extractvalue {i32, i1} %t, 1
+  store i32 %val, i32 *%ptr
+  ret i1 %obit
+}
+
+; Check that subtracting 128 from a spilled value can use ALSI.
+define zeroext i1 @f11(i32 *%ptr, i32 %sel) {
+; CHECK-LABEL: f11:
+; CHECK: alsi {{[0-9]+}}(%r15), -128
+; CHECK: br %r14
+entry:
+  %val0 = load volatile i32, i32 *%ptr
+  %val1 = load volatile i32, i32 *%ptr
+  %val2 = load volatile i32, i32 *%ptr
+  %val3 = load volatile i32, i32 *%ptr
+  %val4 = load volatile i32, i32 *%ptr
+  %val5 = load volatile i32, i32 *%ptr
+  %val6 = load volatile i32, i32 *%ptr
+  %val7 = load volatile i32, i32 *%ptr
+  %val8 = load volatile i32, i32 *%ptr
+  %val9 = load volatile i32, i32 *%ptr
+  %val10 = load volatile i32, i32 *%ptr
+  %val11 = load volatile i32, i32 *%ptr
+  %val12 = load volatile i32, i32 *%ptr
+  %val13 = load volatile i32, i32 *%ptr
+  %val14 = load volatile i32, i32 *%ptr
+  %val15 = load volatile i32, i32 *%ptr
+
+  %test = icmp ne i32 %sel, 0
+  br i1 %test, label %add, label %store
+
+add:
+  %t0 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val0, i32 128)
+  %add0 = extractvalue {i32, i1} %t0, 0
+  %obit0 = extractvalue {i32, i1} %t0, 1
+  %t1 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val1, i32 128)
+  %add1 = extractvalue {i32, i1} %t1, 0
+  %obit1 = extractvalue {i32, i1} %t1, 1
+  %res1 = or i1 %obit0, %obit1
+  %t2 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val2, i32 128)
+  %add2 = extractvalue {i32, i1} %t2, 0
+  %obit2 = extractvalue {i32, i1} %t2, 1
+  %res2 = or i1 %res1, %obit2
+  %t3 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val3, i32 128)
+  %add3 = extractvalue {i32, i1} %t3, 0
+  %obit3 = extractvalue {i32, i1} %t3, 1
+  %res3 = or i1 %res2, %obit3
+  %t4 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val4, i32 128)
+  %add4 = extractvalue {i32, i1} %t4, 0
+  %obit4 = extractvalue {i32, i1} %t4, 1
+  %res4 = or i1 %res3, %obit4
+  %t5 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val5, i32 128)
+  %add5 = extractvalue {i32, i1} %t5, 0
+  %obit5 = extractvalue {i32, i1} %t5, 1
+  %res5 = or i1 %res4, %obit5
+  %t6 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val6, i32 128)
+  %add6 = extractvalue {i32, i1} %t6, 0
+  %obit6 = extractvalue {i32, i1} %t6, 1
+  %res6 = or i1 %res5, %obit6
+  %t7 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val7, i32 128)
+  %add7 = extractvalue {i32, i1} %t7, 0
+  %obit7 = extractvalue {i32, i1} %t7, 1
+  %res7 = or i1 %res6, %obit7
+  %t8 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val8, i32 128)
+  %add8 = extractvalue {i32, i1} %t8, 0
+  %obit8 = extractvalue {i32, i1} %t8, 1
+  %res8 = or i1 %res7, %obit8
+  %t9 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val9, i32 128)
+  %add9 = extractvalue {i32, i1} %t9, 0
+  %obit9 = extractvalue {i32, i1} %t9, 1
+  %res9 = or i1 %res8, %obit9
+  %t10 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val10, i32 128)
+  %add10 = extractvalue {i32, i1} %t10, 0
+  %obit10 = extractvalue {i32, i1} %t10, 1
+  %res10 = or i1 %res9, %obit10
+  %t11 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val11, i32 128)
+  %add11 = extractvalue {i32, i1} %t11, 0
+  %obit11 = extractvalue {i32, i1} %t11, 1
+  %res11 = or i1 %res10, %obit11
+  %t12 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val12, i32 128)
+  %add12 = extractvalue {i32, i1} %t12, 0
+  %obit12 = extractvalue {i32, i1} %t12, 1
+  %res12 = or i1 %res11, %obit12
+  %t13 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val13, i32 128)
+  %add13 = extractvalue {i32, i1} %t13, 0
+  %obit13 = extractvalue {i32, i1} %t13, 1
+  %res13 = or i1 %res12, %obit13
+  %t14 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val14, i32 128)
+  %add14 = extractvalue {i32, i1} %t14, 0
+  %obit14 = extractvalue {i32, i1} %t14, 1
+  %res14 = or i1 %res13, %obit14
+  %t15 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val15, i32 128)
+  %add15 = extractvalue {i32, i1} %t15, 0
+  %obit15 = extractvalue {i32, i1} %t15, 1
+  %res15 = or i1 %res14, %obit15
+
+  br label %store
+
+store:
+  %new0 = phi i32 [ %val0, %entry ], [ %add0, %add ]
+  %new1 = phi i32 [ %val1, %entry ], [ %add1, %add ]
+  %new2 = phi i32 [ %val2, %entry ], [ %add2, %add ]
+  %new3 = phi i32 [ %val3, %entry ], [ %add3, %add ]
+  %new4 = phi i32 [ %val4, %entry ], [ %add4, %add ]
+  %new5 = phi i32 [ %val5, %entry ], [ %add5, %add ]
+  %new6 = phi i32 [ %val6, %entry ], [ %add6, %add ]
+  %new7 = phi i32 [ %val7, %entry ], [ %add7, %add ]
+  %new8 = phi i32 [ %val8, %entry ], [ %add8, %add ]
+  %new9 = phi i32 [ %val9, %entry ], [ %add9, %add ]
+  %new10 = phi i32 [ %val10, %entry ], [ %add10, %add ]
+  %new11 = phi i32 [ %val11, %entry ], [ %add11, %add ]
+  %new12 = phi i32 [ %val12, %entry ], [ %add12, %add ]
+  %new13 = phi i32 [ %val13, %entry ], [ %add13, %add ]
+  %new14 = phi i32 [ %val14, %entry ], [ %add14, %add ]
+  %new15 = phi i32 [ %val15, %entry ], [ %add15, %add ]
+  %res = phi i1 [ 0, %entry ], [ %res15, %add ]
+
+  store volatile i32 %new0, i32 *%ptr
+  store volatile i32 %new1, i32 *%ptr
+  store volatile i32 %new2, i32 *%ptr
+  store volatile i32 %new3, i32 *%ptr
+  store volatile i32 %new4, i32 *%ptr
+  store volatile i32 %new5, i32 *%ptr
+  store volatile i32 %new6, i32 *%ptr
+  store volatile i32 %new7, i32 *%ptr
+  store volatile i32 %new8, i32 *%ptr
+  store volatile i32 %new9, i32 *%ptr
+  store volatile i32 %new10, i32 *%ptr
+  store volatile i32 %new11, i32 *%ptr
+  store volatile i32 %new12, i32 *%ptr
+  store volatile i32 %new13, i32 *%ptr
+  store volatile i32 %new14, i32 *%ptr
+  store volatile i32 %new15, i32 *%ptr
+
+  ret i1 %res
+}
+
+; Check that subtracting -127 from a spilled value can use ALSI.
+define zeroext i1 @f12(i32 *%ptr, i32 %sel) {
+; CHECK-LABEL: f12:
+; CHECK: alsi {{[0-9]+}}(%r15), 127
+; CHECK: br %r14
+entry:
+  %val0 = load volatile i32, i32 *%ptr
+  %val1 = load volatile i32, i32 *%ptr
+  %val2 = load volatile i32, i32 *%ptr
+  %val3 = load volatile i32, i32 *%ptr
+  %val4 = load volatile i32, i32 *%ptr
+  %val5 = load volatile i32, i32 *%ptr
+  %val6 = load volatile i32, i32 *%ptr
+  %val7 = load volatile i32, i32 *%ptr
+  %val8 = load volatile i32, i32 *%ptr
+  %val9 = load volatile i32, i32 *%ptr
+  %val10 = load volatile i32, i32 *%ptr
+  %val11 = load volatile i32, i32 *%ptr
+  %val12 = load volatile i32, i32 *%ptr
+  %val13 = load volatile i32, i32 *%ptr
+  %val14 = load volatile i32, i32 *%ptr
+  %val15 = load volatile i32, i32 *%ptr
+
+  %test = icmp ne i32 %sel, 0
+  br i1 %test, label %add, label %store
+
+add:
+  %t0 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val0, i32 -127)
+  %add0 = extractvalue {i32, i1} %t0, 0
+  %obit0 = extractvalue {i32, i1} %t0, 1
+  %t1 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val1, i32 -127)
+  %add1 = extractvalue {i32, i1} %t1, 0
+  %obit1 = extractvalue {i32, i1} %t1, 1
+  %res1 = or i1 %obit0, %obit1
+  %t2 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val2, i32 -127)
+  %add2 = extractvalue {i32, i1} %t2, 0
+  %obit2 = extractvalue {i32, i1} %t2, 1
+  %res2 = or i1 %res1, %obit2
+  %t3 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val3, i32 -127)
+  %add3 = extractvalue {i32, i1} %t3, 0
+  %obit3 = extractvalue {i32, i1} %t3, 1
+  %res3 = or i1 %res2, %obit3
+  %t4 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val4, i32 -127)
+  %add4 = extractvalue {i32, i1} %t4, 0
+  %obit4 = extractvalue {i32, i1} %t4, 1
+  %res4 = or i1 %res3, %obit4
+  %t5 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val5, i32 -127)
+  %add5 = extractvalue {i32, i1} %t5, 0
+  %obit5 = extractvalue {i32, i1} %t5, 1
+  %res5 = or i1 %res4, %obit5
+  %t6 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val6, i32 -127)
+  %add6 = extractvalue {i32, i1} %t6, 0
+  %obit6 = extractvalue {i32, i1} %t6, 1
+  %res6 = or i1 %res5, %obit6
+  %t7 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val7, i32 -127)
+  %add7 = extractvalue {i32, i1} %t7, 0
+  %obit7 = extractvalue {i32, i1} %t7, 1
+  %res7 = or i1 %res6, %obit7
+  %t8 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val8, i32 -127)
+  %add8 = extractvalue {i32, i1} %t8, 0
+  %obit8 = extractvalue {i32, i1} %t8, 1
+  %res8 = or i1 %res7, %obit8
+  %t9 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val9, i32 -127)
+  %add9 = extractvalue {i32, i1} %t9, 0
+  %obit9 = extractvalue {i32, i1} %t9, 1
+  %res9 = or i1 %res8, %obit9
+  %t10 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val10, i32 -127)
+  %add10 = extractvalue {i32, i1} %t10, 0
+  %obit10 = extractvalue {i32, i1} %t10, 1
+  %res10 = or i1 %res9, %obit10
+  %t11 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val11, i32 -127)
+  %add11 = extractvalue {i32, i1} %t11, 0
+  %obit11 = extractvalue {i32, i1} %t11, 1
+  %res11 = or i1 %res10, %obit11
+  %t12 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val12, i32 -127)
+  %add12 = extractvalue {i32, i1} %t12, 0
+  %obit12 = extractvalue {i32, i1} %t12, 1
+  %res12 = or i1 %res11, %obit12
+  %t13 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val13, i32 -127)
+  %add13 = extractvalue {i32, i1} %t13, 0
+  %obit13 = extractvalue {i32, i1} %t13, 1
+  %res13 = or i1 %res12, %obit13
+  %t14 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val14, i32 -127)
+  %add14 = extractvalue {i32, i1} %t14, 0
+  %obit14 = extractvalue {i32, i1} %t14, 1
+  %res14 = or i1 %res13, %obit14
+  %t15 = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %val15, i32 -127)
+  %add15 = extractvalue {i32, i1} %t15, 0
+  %obit15 = extractvalue {i32, i1} %t15, 1
+  %res15 = or i1 %res14, %obit15
+
+  br label %store
+
+store:
+  %new0 = phi i32 [ %val0, %entry ], [ %add0, %add ]
+  %new1 = phi i32 [ %val1, %entry ], [ %add1, %add ]
+  %new2 = phi i32 [ %val2, %entry ], [ %add2, %add ]
+  %new3 = phi i32 [ %val3, %entry ], [ %add3, %add ]
+  %new4 = phi i32 [ %val4, %entry ], [ %add4, %add ]
+  %new5 = phi i32 [ %val5, %entry ], [ %add5, %add ]
+  %new6 = phi i32 [ %val6, %entry ], [ %add6, %add ]
+  %new7 = phi i32 [ %val7, %entry ], [ %add7, %add ]
+  %new8 = phi i32 [ %val8, %entry ], [ %add8, %add ]
+  %new9 = phi i32 [ %val9, %entry ], [ %add9, %add ]
+  %new10 = phi i32 [ %val10, %entry ], [ %add10, %add ]
+  %new11 = phi i32 [ %val11, %entry ], [ %add11, %add ]
+  %new12 = phi i32 [ %val12, %entry ], [ %add12, %add ]
+  %new13 = phi i32 [ %val13, %entry ], [ %add13, %add ]
+  %new14 = phi i32 [ %val14, %entry ], [ %add14, %add ]
+  %new15 = phi i32 [ %val15, %entry ], [ %add15, %add ]
+  %res = phi i1 [ 0, %entry ], [ %res15, %add ]
+
+  store volatile i32 %new0, i32 *%ptr
+  store volatile i32 %new1, i32 *%ptr
+  store volatile i32 %new2, i32 *%ptr
+  store volatile i32 %new3, i32 *%ptr
+  store volatile i32 %new4, i32 *%ptr
+  store volatile i32 %new5, i32 *%ptr
+  store volatile i32 %new6, i32 *%ptr
+  store volatile i32 %new7, i32 *%ptr
+  store volatile i32 %new8, i32 *%ptr
+  store volatile i32 %new9, i32 *%ptr
+  store volatile i32 %new10, i32 *%ptr
+  store volatile i32 %new11, i32 *%ptr
+  store volatile i32 %new12, i32 *%ptr
+  store volatile i32 %new13, i32 *%ptr
+  store volatile i32 %new14, i32 *%ptr
+  store volatile i32 %new15, i32 *%ptr
+
+  ret i1 %res
+}
+
+; Check using the overflow result for a branch.
+define void @f13(i32 *%ptr) {
+; CHECK-LABEL: f13:
+; CHECK: alsi 0(%r2), -1
+; CHECK: jgle foo@PLT
+; CHECK: br %r14
+  %a = load i32, i32 *%ptr
+  %t = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 1)
+  %val = extractvalue {i32, i1} %t, 0
+  %obit = extractvalue {i32, i1} %t, 1
+  store i32 %val, i32 *%ptr
+  br i1 %obit, label %call, label %exit
+
+call:
+  tail call i32 @foo()
+  br label %exit
+
+exit:
+  ret void
+}
+
+; ... and the same with the inverted direction.
+define void @f14(i32 *%ptr) {
+; CHECK-LABEL: f14:
+; CHECK: alsi 0(%r2), -1
+; CHECK: jgnle foo@PLT
+; CHECK: br %r14
+  %a = load i32, i32 *%ptr
+  %t = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 1)
+  %val = extractvalue {i32, i1} %t, 0
+  %obit = extractvalue {i32, i1} %t, 1
+  store i32 %val, i32 *%ptr
+  br i1 %obit, label %exit, label %call
+
+call:
+  tail call i32 @foo()
+  br label %exit
+
+exit:
+  ret void
+}
+
+declare {i32, i1} @llvm.usub.with.overflow.i32(i32, i32) nounwind readnone
+