Introduce fgDebugCheckTypes

[EgorBo]

• Validate types used in IR nodes.
• Remove varTypeIsSmallInt because it's the same as varTypeIsSmall.
• Remove varTypeGCtype because it's the same as varTypeGC
• Fix small-typed nodes produced by optOptimizeBools (e.g. ubyte GT_OR(op1, op2) ...)
• Fix small-typed nodes used by GT_HWINTRINSIC, e.g. all comparisons and ToScalar

[ghost]

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Issue Details

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Validate types used in IR nodes.

Also, remove varTypeIsSmallInt because it's the same as varTypeIsSmall.

PS: plan to remove the GT_HWINTRINSIC quirk as part of this PR.

Author:	EgorBo
Assignees:	EgorBo
Labels:	area-CodeGen-coreclr
Milestone:	-

[EgorBo]

/azp list

[EgorBo]

/azp run runtime-coreclr outerloop, runtime-coreclr jitstress, runtime-coreclr pgo

[azure-pipelines]

Azure Pipelines successfully started running 3 pipeline(s).

[EgorBo]

the latest diffs are better https://dev.azure.com/dnceng-public/public/_build/results?buildId=467438&view=ms.vss-build-web.run-extensions-tab but there are still regressions because of GT_HWINTRINSIC (mainly around op_Equality)

[EgorBo]

@jakobbotsch @dotnet/jit-contrib PTAL

Small diffs are caused by the GT_HWINTRINSIC changes (there were qute a few trees with small types as IR types)

Size regressions on arm64 seem to be perf improvements - optOptimizeBool kicks in where previously it didn't, e.g.:

(less branches, but larger size), in IR it's:

Main:

***** BB02
N006 ( 11, 10) [000025] -----------                         *  JTRUE     void   $VN.Void
N005 (  9,  8) [000024] J------N---                         \--*  NE        int    $181
N003 (  7,  5) [000176] -----------                            +--*  HWINTRINSIC ubyte  int op_Equality $141
N001 (  3,  2) [000283] -----------                            |  +--*  CNS_VEC   simd16<0x00000005, 0x00000005, 0x00000005, 0x00000005> $101
N002 (  3,  2) [000282] -----------                            |  \--*  CNS_VEC   simd16<0x00000003, 0x00000003, 0x00000003, 0x00000003> $100
N004 (  1,  2) [000023] -----------                            \--*  CNS_INT   int    0 $40

***** BB03
N006 (  9, 10) [000032] -----------                         *  JTRUE     void   $VN.Void
N005 (  7,  8) [000031] J------N---                         \--*  NE        int    $182
N003 (  5,  5) [000207] -----------                            +--*  HWINTRINSIC ubyte  int op_Equality $142
N001 (  1,  2) [000206] -----------                            |  +--*  CNS_VEC   simd16<0x00000000, 0x00000000, 0x00000000, 0x00000000> $102
N002 (  3,  2) [000284] -----------                            |  \--*  CNS_VEC   simd16<0x00000003, 0x00000003, 0x00000003, 0x00000003> $100
N004 (  1,  2) [000030] -----------                            \--*  CNS_INT   int    0 $40

PR:

N010 ( 17, 16) [000025] -----------                         *  JTRUE     void   $VN.Void
N009 ( 15, 14) [000024] J------N---                         \--*  NE        int   
N007 ( 13, 11) [000295] -----------                            +--*  OR        int   
N003 (  7,  5) [000177] -----------                            |  +--*  HWINTRINSIC int    int op_Equality $142
N001 (  3,  2) [000288] -----------                            |  |  +--*  CNS_VEC   simd16<0x00000005, 0x00000005, 0x00000005, 0x00000005> $101
N002 (  3,  2) [000287] -----------                            |  |  \--*  CNS_VEC   simd16<0x00000003, 0x00000003, 0x00000003, 0x00000003> $100
N006 (  5,  5) [000209] -----------                            |  \--*  HWINTRINSIC int    int op_Equality $144

[BruceForstall]

Thanks for doing this! I'm looking forward to all the follow-up work on the TODOs :-)