| ; RUN: llc -mtriple=aarch64-gnu-linux -mcpu=cortex-a57 -enable-unsafe-fp-math -disable-post-ra < %s | FileCheck %s | |
| ; Incremental updates of the instruction depths should be enough for this test | |
| ; case. | |
| ; RUN: llc -mtriple=aarch64-gnu-linux -mcpu=cortex-a57 -enable-unsafe-fp-math \ | |
| ; RUN: -disable-post-ra -machine-combiner-inc-threshold=0 -machine-combiner-verify-pattern-order=true < %s | FileCheck %s | |
| ; Verify that the first two adds are independent regardless of how the inputs are | |
| ; commuted. The destination registers are used as source registers for the third add. | |
| define float @reassociate_adds1(float %x0, float %x1, float %x2, float %x3) { | |
| ; CHECK-LABEL: reassociate_adds1: | |
| ; CHECK: fadd s0, s0, s1 | |
| ; CHECK-NEXT: fadd s1, s2, s3 | |
| ; CHECK-NEXT: fadd s0, s0, s1 | |
| ; CHECK-NEXT: ret | |
| %t0 = fadd float %x0, %x1 | |
| %t1 = fadd float %t0, %x2 | |
| %t2 = fadd float %t1, %x3 | |
| ret float %t2 | |
| } | |
| define float @reassociate_adds2(float %x0, float %x1, float %x2, float %x3) { | |
| ; CHECK-LABEL: reassociate_adds2: | |
| ; CHECK: fadd s0, s0, s1 | |
| ; CHECK-NEXT: fadd s1, s2, s3 | |
| ; CHECK-NEXT: fadd s0, s0, s1 | |
| ; CHECK-NEXT: ret | |
| %t0 = fadd float %x0, %x1 | |
| %t1 = fadd float %x2, %t0 | |
| %t2 = fadd float %t1, %x3 | |
| ret float %t2 | |
| } | |
| define float @reassociate_adds3(float %x0, float %x1, float %x2, float %x3) { | |
| ; CHECK-LABEL: reassociate_adds3: | |
| ; CHECK: s0, s0, s1 | |
| ; CHECK-NEXT: s1, s2, s3 | |
| ; CHECK-NEXT: s0, s0, s1 | |
| ; CHECK-NEXT: ret | |
| %t0 = fadd float %x0, %x1 | |
| %t1 = fadd float %t0, %x2 | |
| %t2 = fadd float %x3, %t1 | |
| ret float %t2 | |
| } | |
| define float @reassociate_adds4(float %x0, float %x1, float %x2, float %x3) { | |
| ; CHECK-LABEL: reassociate_adds4: | |
| ; CHECK: s0, s0, s1 | |
| ; CHECK-NEXT: s1, s2, s3 | |
| ; CHECK-NEXT: s0, s0, s1 | |
| ; CHECK-NEXT: ret | |
| %t0 = fadd float %x0, %x1 | |
| %t1 = fadd float %x2, %t0 | |
| %t2 = fadd float %x3, %t1 | |
| ret float %t2 | |
| } | |
| ; Verify that we reassociate some of these ops. The optimal balanced tree of adds is not | |
| ; produced because that would cost more compile time. | |
| define float @reassociate_adds5(float %x0, float %x1, float %x2, float %x3, float %x4, float %x5, float %x6, float %x7) { | |
| ; CHECK-LABEL: reassociate_adds5: | |
| ; CHECK: fadd s0, s0, s1 | |
| ; CHECK-NEXT: fadd s1, s2, s3 | |
| ; CHECK-NEXT: fadd s0, s0, s1 | |
| ; CHECK-NEXT: fadd s1, s4, s5 | |
| ; CHECK-NEXT: fadd s1, s1, s6 | |
| ; CHECK-NEXT: fadd s0, s0, s1 | |
| ; CHECK-NEXT: fadd s0, s0, s7 | |
| ; CHECK-NEXT: ret | |
| %t0 = fadd float %x0, %x1 | |
| %t1 = fadd float %t0, %x2 | |
| %t2 = fadd float %t1, %x3 | |
| %t3 = fadd float %t2, %x4 | |
| %t4 = fadd float %t3, %x5 | |
| %t5 = fadd float %t4, %x6 | |
| %t6 = fadd float %t5, %x7 | |
| ret float %t6 | |
| } | |
| ; Verify that we only need two associative operations to reassociate the operands. | |
| ; Also, we should reassociate such that the result of the high latency division | |
| ; is used by the final 'add' rather than reassociating the %x3 operand with the | |
| ; division. The latter reassociation would not improve anything. | |
| define float @reassociate_adds6(float %x0, float %x1, float %x2, float %x3) { | |
| ; CHECK-LABEL: reassociate_adds6: | |
| ; CHECK: fdiv s0, s0, s1 | |
| ; CHECK-NEXT: fadd s1, s2, s3 | |
| ; CHECK-NEXT: fadd s0, s0, s1 | |
| ; CHECK-NEXT: ret | |
| %t0 = fdiv float %x0, %x1 | |
| %t1 = fadd float %x2, %t0 | |
| %t2 = fadd float %x3, %t1 | |
| ret float %t2 | |
| } | |
| ; Verify that scalar single-precision multiplies are reassociated. | |
| define float @reassociate_muls1(float %x0, float %x1, float %x2, float %x3) { | |
| ; CHECK-LABEL: reassociate_muls1: | |
| ; CHECK: fdiv s0, s0, s1 | |
| ; CHECK-NEXT: fmul s1, s2, s3 | |
| ; CHECK-NEXT: fmul s0, s0, s1 | |
| ; CHECK-NEXT: ret | |
| %t0 = fdiv float %x0, %x1 | |
| %t1 = fmul float %x2, %t0 | |
| %t2 = fmul float %x3, %t1 | |
| ret float %t2 | |
| } | |
| ; Verify that scalar double-precision adds are reassociated. | |
| define double @reassociate_adds_double(double %x0, double %x1, double %x2, double %x3) { | |
| ; CHECK-LABEL: reassociate_adds_double: | |
| ; CHECK: fdiv d0, d0, d1 | |
| ; CHECK-NEXT: fadd d1, d2, d3 | |
| ; CHECK-NEXT: fadd d0, d0, d1 | |
| ; CHECK-NEXT: ret | |
| %t0 = fdiv double %x0, %x1 | |
| %t1 = fadd double %x2, %t0 | |
| %t2 = fadd double %x3, %t1 | |
| ret double %t2 | |
| } | |
| ; Verify that scalar double-precision multiplies are reassociated. | |
| define double @reassociate_muls_double(double %x0, double %x1, double %x2, double %x3) { | |
| ; CHECK-LABEL: reassociate_muls_double: | |
| ; CHECK: fdiv d0, d0, d1 | |
| ; CHECK-NEXT: fmul d1, d2, d3 | |
| ; CHECK-NEXT: fmul d0, d0, d1 | |
| ; CHECK-NEXT: ret | |
| %t0 = fdiv double %x0, %x1 | |
| %t1 = fmul double %x2, %t0 | |
| %t2 = fmul double %x3, %t1 | |
| ret double %t2 | |
| } | |
| ; Verify that we reassociate vector instructions too. | |
| define <4 x float> @vector_reassociate_adds1(<4 x float> %x0, <4 x float> %x1, <4 x float> %x2, <4 x float> %x3) { | |
| ; CHECK-LABEL: vector_reassociate_adds1: | |
| ; CHECK: fadd v0.4s, v0.4s, v1.4s | |
| ; CHECK-NEXT: fadd v1.4s, v2.4s, v3.4s | |
| ; CHECK-NEXT: fadd v0.4s, v0.4s, v1.4s | |
| ; CHECK-NEXT: ret | |
| %t0 = fadd <4 x float> %x0, %x1 | |
| %t1 = fadd <4 x float> %t0, %x2 | |
| %t2 = fadd <4 x float> %t1, %x3 | |
| ret <4 x float> %t2 | |
| } | |
| define <4 x float> @vector_reassociate_adds2(<4 x float> %x0, <4 x float> %x1, <4 x float> %x2, <4 x float> %x3) { | |
| ; CHECK-LABEL: vector_reassociate_adds2: | |
| ; CHECK: fadd v0.4s, v0.4s, v1.4s | |
| ; CHECK-NEXT: fadd v1.4s, v2.4s, v3.4s | |
| ; CHECK-NEXT: fadd v0.4s, v0.4s, v1.4s | |
| %t0 = fadd <4 x float> %x0, %x1 | |
| %t1 = fadd <4 x float> %x2, %t0 | |
| %t2 = fadd <4 x float> %t1, %x3 | |
| ret <4 x float> %t2 | |
| } | |
| define <4 x float> @vector_reassociate_adds3(<4 x float> %x0, <4 x float> %x1, <4 x float> %x2, <4 x float> %x3) { | |
| ; CHECK-LABEL: vector_reassociate_adds3: | |
| ; CHECK: fadd v0.4s, v0.4s, v1.4s | |
| ; CHECK-NEXT: fadd v1.4s, v2.4s, v3.4s | |
| ; CHECK-NEXT: fadd v0.4s, v0.4s, v1.4s | |
| %t0 = fadd <4 x float> %x0, %x1 | |
| %t1 = fadd <4 x float> %t0, %x2 | |
| %t2 = fadd <4 x float> %x3, %t1 | |
| ret <4 x float> %t2 | |
| } | |
| define <4 x float> @vector_reassociate_adds4(<4 x float> %x0, <4 x float> %x1, <4 x float> %x2, <4 x float> %x3) { | |
| ; CHECK-LABEL: vector_reassociate_adds4: | |
| ; CHECK: fadd v0.4s, v0.4s, v1.4s | |
| ; CHECK-NEXT: fadd v1.4s, v2.4s, v3.4s | |
| ; CHECK-NEXT: fadd v0.4s, v0.4s, v1.4s | |
| %t0 = fadd <4 x float> %x0, %x1 | |
| %t1 = fadd <4 x float> %x2, %t0 | |
| %t2 = fadd <4 x float> %x3, %t1 | |
| ret <4 x float> %t2 | |
| } | |
| ; Verify that 128-bit vector single-precision multiplies are reassociated. | |
| define <4 x float> @reassociate_muls_v4f32(<4 x float> %x0, <4 x float> %x1, <4 x float> %x2, <4 x float> %x3) { | |
| ; CHECK-LABEL: reassociate_muls_v4f32: | |
| ; CHECK: fadd v0.4s, v0.4s, v1.4s | |
| ; CHECK-NEXT: fmul v1.4s, v2.4s, v3.4s | |
| ; CHECK-NEXT: fmul v0.4s, v0.4s, v1.4s | |
| ; CHECK-NEXT: ret | |
| %t0 = fadd <4 x float> %x0, %x1 | |
| %t1 = fmul <4 x float> %x2, %t0 | |
| %t2 = fmul <4 x float> %x3, %t1 | |
| ret <4 x float> %t2 | |
| } | |
| ; Verify that 128-bit vector double-precision multiplies are reassociated. | |
| define <2 x double> @reassociate_muls_v2f64(<2 x double> %x0, <2 x double> %x1, <2 x double> %x2, <2 x double> %x3) { | |
| ; CHECK-LABEL: reassociate_muls_v2f64: | |
| ; CHECK: fadd v0.2d, v0.2d, v1.2d | |
| ; CHECK-NEXT: fmul v1.2d, v2.2d, v3.2d | |
| ; CHECK-NEXT: fmul v0.2d, v0.2d, v1.2d | |
| ; CHECK-NEXT: ret | |
| %t0 = fadd <2 x double> %x0, %x1 | |
| %t1 = fmul <2 x double> %x2, %t0 | |
| %t2 = fmul <2 x double> %x3, %t1 | |
| ret <2 x double> %t2 | |
| } | |
| ; PR25016: https://llvm.org/bugs/show_bug.cgi?id=25016 | |
| ; Verify that reassociation is not happening needlessly or wrongly. | |
| declare double @bar() | |
| define double @reassociate_adds_from_calls() { | |
| ; CHECK-LABEL: reassociate_adds_from_calls: | |
| ; CHECK: bl bar | |
| ; CHECK-NEXT: mov v8.16b, v0.16b | |
| ; CHECK-NEXT: bl bar | |
| ; CHECK-NEXT: mov v9.16b, v0.16b | |
| ; CHECK-NEXT: bl bar | |
| ; CHECK-NEXT: mov v10.16b, v0.16b | |
| ; CHECK-NEXT: bl bar | |
| ; CHECK: fadd d1, d8, d9 | |
| ; CHECK-NEXT: fadd d0, d10, d0 | |
| ; CHECK-NEXT: fadd d0, d1, d0 | |
| %x0 = call double @bar() | |
| %x1 = call double @bar() | |
| %x2 = call double @bar() | |
| %x3 = call double @bar() | |
| %t0 = fadd double %x0, %x1 | |
| %t1 = fadd double %t0, %x2 | |
| %t2 = fadd double %t1, %x3 | |
| ret double %t2 | |
| } | |
| define double @already_reassociated() { | |
| ; CHECK-LABEL: already_reassociated: | |
| ; CHECK: bl bar | |
| ; CHECK-NEXT: mov v8.16b, v0.16b | |
| ; CHECK-NEXT: bl bar | |
| ; CHECK-NEXT: mov v9.16b, v0.16b | |
| ; CHECK-NEXT: bl bar | |
| ; CHECK-NEXT: mov v10.16b, v0.16b | |
| ; CHECK-NEXT: bl bar | |
| ; CHECK: fadd d1, d8, d9 | |
| ; CHECK-NEXT: fadd d0, d10, d0 | |
| ; CHECK-NEXT: fadd d0, d1, d0 | |
| %x0 = call double @bar() | |
| %x1 = call double @bar() | |
| %x2 = call double @bar() | |
| %x3 = call double @bar() | |
| %t0 = fadd double %x0, %x1 | |
| %t1 = fadd double %x2, %x3 | |
| %t2 = fadd double %t0, %t1 | |
| ret double %t2 | |
| } | |