1 # RUN: llc -march=hexagon -run-pass hwloops %s -o - | FileCheck %s 2 3 # Normally, if the registers holding the induction variable's bounds 4 # are redefined inside of the loop's body, the loop cannot be converted 5 # to a hardware loop. However, if the redefining instruction is actually 6 # loading an immediate value into the register, this conversion is both 7 # possible and legal (since the immediate itself will be used in the 8 # loop setup in the preheader). 9 10 # CHECK: [[R0:%[0-9]+]]:intregs = A2_tfrsi 1920 11 # CHECK: J2_loop0r %bb.1, [[R0]] 12 # 13 # CHECK: bb.1.b1 (address-taken): 14 # CHECK: ENDLOOP0 %bb.1 15 16 17 --- | 18 define void @fred() { 19 b0: 20 br label %b1 21 b1: 22 br label %b2 23 b2: 24 ret void 25 } 26 ... 27 28 --- 29 name: fred 30 tracksRegLiveness: true 31 registers: 32 - { id: 0, class: intregs } 33 - { id: 1, class: intregs } 34 - { id: 2, class: intregs } 35 - { id: 3, class: intregs } 36 - { id: 4, class: intregs } 37 - { id: 5, class: intregs } 38 - { id: 6, class: intregs } 39 - { id: 7, class: intregs } 40 - { id: 8, class: predregs } 41 body: | 42 bb.0.b0: 43 liveins: $r0 44 successors: %bb.1 45 %0 = A2_tfrsi 0 46 %1 = A2_tfrsi 0 47 %2 = COPY $r0 48 49 bb.1.b1: 50 successors: %bb.1, %bb.2 51 %3 = PHI %0, %bb.0, %6, %bb.1 52 %4 = PHI %1, %bb.0, %5, %bb.1 53 S4_storerh_rr %2, %4, 0, %3 54 %5 = A2_addi %4, 2 55 %6 = A2_addi %3, 1 56 ; This definition of %7 should not prevent conversion to hardware loop. 57 %7 = A2_tfrsi 3840 58 %8 = C2_cmpeq %5, %7 59 J2_jumpf %8, %bb.1, implicit-def $pc 60 J2_jump %bb.2, implicit-def $pc 61 62 bb.2.b2: 63 ... 64
