[PATCH] D102834: [SLPVectorizer] Implement initial memory versioning.

[Florian Hahn via Phabricator via llvm-commits]

fhahn added inline comments.


================
Comment at: llvm/test/Transforms/SLPVectorizer/AArch64/loadi8.ll:104
 ; CHECK-LABEL: @f_alias(
-; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[SCALE:%.*]] = getelementptr inbounds [[STRUCT_WEIGHT_T:%.*]], %struct.weight_t* [[W:%.*]], i64 0, i32 0
-; CHECK-NEXT:    [[TMP0:%.*]] = load i32, i32* [[SCALE]], align 16
-; CHECK-NEXT:    [[OFFSET:%.*]] = getelementptr inbounds [[STRUCT_WEIGHT_T]], %struct.weight_t* [[W]], i64 0, i32 1
-; CHECK-NEXT:    [[TMP1:%.*]] = load i32, i32* [[OFFSET]], align 4
-; CHECK-NEXT:    [[TMP2:%.*]] = load i8, i8* [[SRC:%.*]], align 1
-; CHECK-NEXT:    [[CONV:%.*]] = zext i8 [[TMP2]] to i32
-; CHECK-NEXT:    [[MUL:%.*]] = mul nsw i32 [[TMP0]], [[CONV]]
-; CHECK-NEXT:    [[ADD:%.*]] = add nsw i32 [[MUL]], [[TMP1]]
-; CHECK-NEXT:    [[TOBOOL_NOT_I:%.*]] = icmp ult i32 [[ADD]], 256
-; CHECK-NEXT:    [[TMP3:%.*]] = icmp sgt i32 [[ADD]], 0
-; CHECK-NEXT:    [[SHR_I:%.*]] = sext i1 [[TMP3]] to i32
-; CHECK-NEXT:    [[COND_I:%.*]] = select i1 [[TOBOOL_NOT_I]], i32 [[ADD]], i32 [[SHR_I]]
-; CHECK-NEXT:    [[CONV_I:%.*]] = trunc i32 [[COND_I]] to i8
-; CHECK-NEXT:    store i8 [[CONV_I]], i8* [[DST:%.*]], align 1
-; CHECK-NEXT:    [[ARRAYIDX_1:%.*]] = getelementptr inbounds i8, i8* [[SRC]], i64 1
-; CHECK-NEXT:    [[TMP4:%.*]] = load i8, i8* [[ARRAYIDX_1]], align 1
-; CHECK-NEXT:    [[CONV_1:%.*]] = zext i8 [[TMP4]] to i32
-; CHECK-NEXT:    [[MUL_1:%.*]] = mul nsw i32 [[TMP0]], [[CONV_1]]
-; CHECK-NEXT:    [[ADD_1:%.*]] = add nsw i32 [[MUL_1]], [[TMP1]]
-; CHECK-NEXT:    [[TOBOOL_NOT_I_1:%.*]] = icmp ult i32 [[ADD_1]], 256
-; CHECK-NEXT:    [[TMP5:%.*]] = icmp sgt i32 [[ADD_1]], 0
-; CHECK-NEXT:    [[SHR_I_1:%.*]] = sext i1 [[TMP5]] to i32
-; CHECK-NEXT:    [[COND_I_1:%.*]] = select i1 [[TOBOOL_NOT_I_1]], i32 [[ADD_1]], i32 [[SHR_I_1]]
-; CHECK-NEXT:    [[CONV_I_1:%.*]] = trunc i32 [[COND_I_1]] to i8
-; CHECK-NEXT:    [[ARRAYIDX2_1:%.*]] = getelementptr inbounds i8, i8* [[DST]], i64 1
-; CHECK-NEXT:    store i8 [[CONV_I_1]], i8* [[ARRAYIDX2_1]], align 1
-; CHECK-NEXT:    [[ARRAYIDX_2:%.*]] = getelementptr inbounds i8, i8* [[SRC]], i64 2
-; CHECK-NEXT:    [[TMP6:%.*]] = load i8, i8* [[ARRAYIDX_2]], align 1
-; CHECK-NEXT:    [[CONV_2:%.*]] = zext i8 [[TMP6]] to i32
-; CHECK-NEXT:    [[MUL_2:%.*]] = mul nsw i32 [[TMP0]], [[CONV_2]]
-; CHECK-NEXT:    [[ADD_2:%.*]] = add nsw i32 [[MUL_2]], [[TMP1]]
-; CHECK-NEXT:    [[TOBOOL_NOT_I_2:%.*]] = icmp ult i32 [[ADD_2]], 256
-; CHECK-NEXT:    [[TMP7:%.*]] = icmp sgt i32 [[ADD_2]], 0
-; CHECK-NEXT:    [[SHR_I_2:%.*]] = sext i1 [[TMP7]] to i32
-; CHECK-NEXT:    [[COND_I_2:%.*]] = select i1 [[TOBOOL_NOT_I_2]], i32 [[ADD_2]], i32 [[SHR_I_2]]
-; CHECK-NEXT:    [[CONV_I_2:%.*]] = trunc i32 [[COND_I_2]] to i8
-; CHECK-NEXT:    [[ARRAYIDX2_2:%.*]] = getelementptr inbounds i8, i8* [[DST]], i64 2
-; CHECK-NEXT:    store i8 [[CONV_I_2]], i8* [[ARRAYIDX2_2]], align 1
-; CHECK-NEXT:    [[ARRAYIDX_3:%.*]] = getelementptr inbounds i8, i8* [[SRC]], i64 3
-; CHECK-NEXT:    [[TMP8:%.*]] = load i8, i8* [[ARRAYIDX_3]], align 1
-; CHECK-NEXT:    [[CONV_3:%.*]] = zext i8 [[TMP8]] to i32
-; CHECK-NEXT:    [[MUL_3:%.*]] = mul nsw i32 [[TMP0]], [[CONV_3]]
-; CHECK-NEXT:    [[ADD_3:%.*]] = add nsw i32 [[MUL_3]], [[TMP1]]
-; CHECK-NEXT:    [[TOBOOL_NOT_I_3:%.*]] = icmp ult i32 [[ADD_3]], 256
-; CHECK-NEXT:    [[TMP9:%.*]] = icmp sgt i32 [[ADD_3]], 0
-; CHECK-NEXT:    [[SHR_I_3:%.*]] = sext i1 [[TMP9]] to i32
-; CHECK-NEXT:    [[COND_I_3:%.*]] = select i1 [[TOBOOL_NOT_I_3]], i32 [[ADD_3]], i32 [[SHR_I_3]]
-; CHECK-NEXT:    [[CONV_I_3:%.*]] = trunc i32 [[COND_I_3]] to i8
-; CHECK-NEXT:    [[ARRAYIDX2_3:%.*]] = getelementptr inbounds i8, i8* [[DST]], i64 3
-; CHECK-NEXT:    store i8 [[CONV_I_3]], i8* [[ARRAYIDX2_3]], align 1
+; CHECK-NEXT:  entry.slpmemcheck:
+; CHECK-NEXT:    [[SCEVGEP:%.*]] = getelementptr i8, i8* [[DST:%.*]], i64 4
----------------
SjoerdMeijer wrote:
> ABataev wrote:
> > What's changed here? Just the code growths?
> Was wondering the same. To me it looks like we are emitting the runtime checks, but still not vectorising, which we probably want to avoid.
This is what happens if versioning was attempted, but did not enable SLP vectorisation for the block. Probably a case where some memory operations where excluded for some reason. I'll investigate.

The versioned block has been deleted, but the dead runtime checks still remain, but those should be cleaned up by some later pass.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D102834/new/

https://reviews.llvm.org/D102834