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1; RUN: llc < %s -mtriple=thumbv7-apple-ios -mcpu=cortex-a8 | FileCheck %s2 3; ARM has a peephole optimization which looks for a def / use pair. The def4; produces a 32-bit immediate which is consumed by the use. It tries to 5; fold the immediate by breaking it into two parts and fold them into the6; immmediate fields of two uses. e.g7; movw r2, #408858; movt r3, #465409; add r0, r0, r310; =>11; add.w r0, r0, #301989888012; add.w r0, r0, #3014656013;14; However, this transformation is incorrect if the user produces a flag. e.g.15; movw r2, #4088516; movt r3, #4654017; adds r0, r0, r318; =>19; add.w r0, r0, #301989888020; adds.w r0, r0, #3014656021; Note the adds.w may not set the carry flag even if the original sequence22; would.23;24; rdar://1111618925define i64 @t(i64 %aInput) nounwind {26; CHECK-LABEL: t:27; CHECK: movs [[REG:(r[0-9]+)]], #028; CHECK: movt [[REG]], #4654029; CHECK: adds r{{[0-9]+}}, r{{[0-9]+}}, [[REG]]30 %1 = mul i64 %aInput, 100000031 %2 = add i64 %1, -795261838919493222432 ret i64 %233}34