llvm-mirror/test/Transforms/LoopVectorize/float-minmax-instruction-flag.ll
Florian Hahn 639aa30744 [LV] Either get invariant condition OR vector condition.
Currently we unconditionally get the first lane of the condition
operand, even if we later use the full vector condition. This can result
in some unnecessary instructions being generated.

Suggested as follow-up in D80219.
2020-05-24 17:16:42 +01:00

158 lines
7.7 KiB
LLVM

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -loop-vectorize -force-vector-width=4 -S | FileCheck %s
; The function finds the smallest value from a float vector.
; Check if vectorization is enabled by instruction flag `fcmp nnan`.
define float @minloop(float* nocapture readonly %arg) {
; CHECK-LABEL: @minloop(
; CHECK-NEXT: top:
; CHECK-NEXT: [[T:%.*]] = load float, float* [[ARG:%.*]], align 4
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[T1:%.*]] = phi i64 [ [[T7:%.*]], [[LOOP]] ], [ 1, [[TOP:%.*]] ]
; CHECK-NEXT: [[T2:%.*]] = phi float [ [[T6:%.*]], [[LOOP]] ], [ [[T]], [[TOP]] ]
; CHECK-NEXT: [[T3:%.*]] = getelementptr float, float* [[ARG]], i64 [[T1]]
; CHECK-NEXT: [[T4:%.*]] = load float, float* [[T3]], align 4
; CHECK-NEXT: [[T5:%.*]] = fcmp nnan olt float [[T2]], [[T4]]
; CHECK-NEXT: [[T6]] = select i1 [[T5]], float [[T2]], float [[T4]]
; CHECK-NEXT: [[T7]] = add i64 [[T1]], 1
; CHECK-NEXT: [[T8:%.*]] = icmp eq i64 [[T7]], 65537
; CHECK-NEXT: br i1 [[T8]], label [[OUT:%.*]], label [[LOOP]]
; CHECK: out:
; CHECK-NEXT: [[T6_LCSSA:%.*]] = phi float [ [[T6]], [[LOOP]] ]
; CHECK-NEXT: ret float [[T6_LCSSA]]
;
top:
%t = load float, float* %arg
br label %loop
loop: ; preds = %loop, %top
%t1 = phi i64 [ %t7, %loop ], [ 1, %top ]
%t2 = phi float [ %t6, %loop ], [ %t, %top ]
%t3 = getelementptr float, float* %arg, i64 %t1
%t4 = load float, float* %t3, align 4
%t5 = fcmp nnan olt float %t2, %t4
%t6 = select i1 %t5, float %t2, float %t4
%t7 = add i64 %t1, 1
%t8 = icmp eq i64 %t7, 65537
br i1 %t8, label %out, label %loop
out: ; preds = %loop
ret float %t6
}
; Check if vectorization is still enabled by function attribute.
define float @minloopattr(float* nocapture readonly %arg) #0 {
; CHECK-LABEL: @minloopattr(
; CHECK-NEXT: top:
; CHECK-NEXT: [[T:%.*]] = load float, float* [[ARG:%.*]], align 4
; CHECK-NEXT: br i1 false, label [[SCALAR_PH:%.*]], label [[VECTOR_PH:%.*]]
; CHECK: vector.ph:
; CHECK-NEXT: [[MINMAX_IDENT_SPLATINSERT:%.*]] = insertelement <4 x float> undef, float [[T]], i32 0
; CHECK-NEXT: [[MINMAX_IDENT_SPLAT:%.*]] = shufflevector <4 x float> [[MINMAX_IDENT_SPLATINSERT]], <4 x float> undef, <4 x i32> zeroinitializer
; CHECK-NEXT: br label [[VECTOR_BODY:%.*]]
; CHECK: vector.body:
; CHECK-NEXT: [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]
; CHECK-NEXT: [[VEC_PHI:%.*]] = phi <4 x float> [ [[MINMAX_IDENT_SPLAT]], [[VECTOR_PH]] ], [ [[TMP5:%.*]], [[VECTOR_BODY]] ]
; CHECK-NEXT: [[OFFSET_IDX:%.*]] = add i64 1, [[INDEX]]
; CHECK-NEXT: [[TMP0:%.*]] = add i64 [[OFFSET_IDX]], 0
; CHECK-NEXT: [[TMP1:%.*]] = getelementptr float, float* [[ARG]], i64 [[TMP0]]
; CHECK-NEXT: [[TMP2:%.*]] = getelementptr float, float* [[TMP1]], i32 0
; CHECK-NEXT: [[TMP3:%.*]] = bitcast float* [[TMP2]] to <4 x float>*
; CHECK-NEXT: [[WIDE_LOAD:%.*]] = load <4 x float>, <4 x float>* [[TMP3]], align 4
; CHECK-NEXT: [[TMP4:%.*]] = fcmp olt <4 x float> [[VEC_PHI]], [[WIDE_LOAD]]
; CHECK-NEXT: [[TMP5]] = select <4 x i1> [[TMP4]], <4 x float> [[VEC_PHI]], <4 x float> [[WIDE_LOAD]]
; CHECK-NEXT: [[INDEX_NEXT]] = add i64 [[INDEX]], 4
; CHECK-NEXT: [[TMP6:%.*]] = icmp eq i64 [[INDEX_NEXT]], 65536
; CHECK-NEXT: br i1 [[TMP6]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop !0
; CHECK: middle.block:
; CHECK-NEXT: [[RDX_SHUF:%.*]] = shufflevector <4 x float> [[TMP5]], <4 x float> undef, <4 x i32> <i32 2, i32 3, i32 undef, i32 undef>
; CHECK-NEXT: [[RDX_MINMAX_CMP:%.*]] = fcmp fast olt <4 x float> [[TMP5]], [[RDX_SHUF]]
; CHECK-NEXT: [[RDX_MINMAX_SELECT:%.*]] = select fast <4 x i1> [[RDX_MINMAX_CMP]], <4 x float> [[TMP5]], <4 x float> [[RDX_SHUF]]
; CHECK-NEXT: [[RDX_SHUF1:%.*]] = shufflevector <4 x float> [[RDX_MINMAX_SELECT]], <4 x float> undef, <4 x i32> <i32 1, i32 undef, i32 undef, i32 undef>
; CHECK-NEXT: [[RDX_MINMAX_CMP2:%.*]] = fcmp fast olt <4 x float> [[RDX_MINMAX_SELECT]], [[RDX_SHUF1]]
; CHECK-NEXT: [[RDX_MINMAX_SELECT3:%.*]] = select fast <4 x i1> [[RDX_MINMAX_CMP2]], <4 x float> [[RDX_MINMAX_SELECT]], <4 x float> [[RDX_SHUF1]]
; CHECK-NEXT: [[TMP7:%.*]] = extractelement <4 x float> [[RDX_MINMAX_SELECT3]], i32 0
; CHECK-NEXT: [[CMP_N:%.*]] = icmp eq i64 65536, 65536
; CHECK-NEXT: br i1 [[CMP_N]], label [[OUT:%.*]], label [[SCALAR_PH]]
; CHECK: scalar.ph:
; CHECK-NEXT: [[BC_RESUME_VAL:%.*]] = phi i64 [ 65537, [[MIDDLE_BLOCK]] ], [ 1, [[TOP:%.*]] ]
; CHECK-NEXT: [[BC_MERGE_RDX:%.*]] = phi float [ [[T]], [[TOP]] ], [ [[TMP7]], [[MIDDLE_BLOCK]] ]
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[T1:%.*]] = phi i64 [ [[T7:%.*]], [[LOOP]] ], [ [[BC_RESUME_VAL]], [[SCALAR_PH]] ]
; CHECK-NEXT: [[T2:%.*]] = phi float [ [[T6:%.*]], [[LOOP]] ], [ [[BC_MERGE_RDX]], [[SCALAR_PH]] ]
; CHECK-NEXT: [[T3:%.*]] = getelementptr float, float* [[ARG]], i64 [[T1]]
; CHECK-NEXT: [[T4:%.*]] = load float, float* [[T3]], align 4
; CHECK-NEXT: [[T5:%.*]] = fcmp olt float [[T2]], [[T4]]
; CHECK-NEXT: [[T6]] = select i1 [[T5]], float [[T2]], float [[T4]]
; CHECK-NEXT: [[T7]] = add i64 [[T1]], 1
; CHECK-NEXT: [[T8:%.*]] = icmp eq i64 [[T7]], 65537
; CHECK-NEXT: br i1 [[T8]], label [[OUT]], label [[LOOP]], !llvm.loop !2
; CHECK: out:
; CHECK-NEXT: [[T6_LCSSA:%.*]] = phi float [ [[T6]], [[LOOP]] ], [ [[TMP7]], [[MIDDLE_BLOCK]] ]
; CHECK-NEXT: ret float [[T6_LCSSA]]
;
top:
%t = load float, float* %arg
br label %loop
loop: ; preds = %loop, %top
%t1 = phi i64 [ %t7, %loop ], [ 1, %top ]
%t2 = phi float [ %t6, %loop ], [ %t, %top ]
%t3 = getelementptr float, float* %arg, i64 %t1
%t4 = load float, float* %t3, align 4
%t5 = fcmp olt float %t2, %t4
%t6 = select i1 %t5, float %t2, float %t4
%t7 = add i64 %t1, 1
%t8 = icmp eq i64 %t7, 65537
br i1 %t8, label %out, label %loop
out: ; preds = %loop
ret float %t6
}
; Check if vectorization is prevented without the flag or attribute.
define float @minloopnovec(float* nocapture readonly %arg) {
; CHECK-LABEL: @minloopnovec(
; CHECK-NEXT: top:
; CHECK-NEXT: [[T:%.*]] = load float, float* [[ARG:%.*]], align 4
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[T1:%.*]] = phi i64 [ [[T7:%.*]], [[LOOP]] ], [ 1, [[TOP:%.*]] ]
; CHECK-NEXT: [[T2:%.*]] = phi float [ [[T6:%.*]], [[LOOP]] ], [ [[T]], [[TOP]] ]
; CHECK-NEXT: [[T3:%.*]] = getelementptr float, float* [[ARG]], i64 [[T1]]
; CHECK-NEXT: [[T4:%.*]] = load float, float* [[T3]], align 4
; CHECK-NEXT: [[T5:%.*]] = fcmp olt float [[T2]], [[T4]]
; CHECK-NEXT: [[T6]] = select i1 [[T5]], float [[T2]], float [[T4]]
; CHECK-NEXT: [[T7]] = add i64 [[T1]], 1
; CHECK-NEXT: [[T8:%.*]] = icmp eq i64 [[T7]], 65537
; CHECK-NEXT: br i1 [[T8]], label [[OUT:%.*]], label [[LOOP]]
; CHECK: out:
; CHECK-NEXT: [[T6_LCSSA:%.*]] = phi float [ [[T6]], [[LOOP]] ]
; CHECK-NEXT: ret float [[T6_LCSSA]]
;
top:
%t = load float, float* %arg
br label %loop
loop: ; preds = %loop, %top
%t1 = phi i64 [ %t7, %loop ], [ 1, %top ]
%t2 = phi float [ %t6, %loop ], [ %t, %top ]
%t3 = getelementptr float, float* %arg, i64 %t1
%t4 = load float, float* %t3, align 4
%t5 = fcmp olt float %t2, %t4
%t6 = select i1 %t5, float %t2, float %t4
%t7 = add i64 %t1, 1
%t8 = icmp eq i64 %t7, 65537
br i1 %t8, label %out, label %loop
out: ; preds = %loop
ret float %t6
}
attributes #0 = { "no-nans-fp-math"="true" }