7faf1a0868
This patch adds a pass that provides workarounds for the errata described in GRLIB-TN-0009, GRLIB-TN-0010, GRLIB-TN-0011, GRLIB-TN-0012, and GRLIB-TN-0013, that are applicable to the GR712RC and UT700. The documents are available for download from here: https://www.gaisler.com/index.php/information/app-tech-notes The pass will detect certain sensitive instruction sequences and prevent them from occurring by inserting NOP instruction. Below is an overview of each of the workarounds. A similar implementation is available in GCC. GRLIB-TN-0009: * Insert NOPs to prevent the sequence (stb/sth/st/stf) -> (single non-store/load instruction) -> (any store) * Insert NOPs to prevent the sequence (std/stdf) -> (any store) GRLIB-TN-0010: * Insert a NOP between load instruction and atomic instruction (swap and casa). * Insert a NOP at branch target if load in delay slot and atomic instruction at branch target. * Do not allow functions to begin with atomic instruction. GRLIB-TN-0011: * Insert .p2align 4 before atomic instructions (swap and casa). GRLIB-TN-0012: * Place a NOP at the branch target of an integer branch if it is a floating-point operation or a floating-point branch. GRLIB-TN-0013: * Prevent (div/sqrt) instructions in the delay slot. * Insert NOPs to prevent the sequence (div/sqrt) -> (two or three floating point operations or loads) -> (div/sqrt). * Do not insert NOPs if any of the floating point operations have a dependency on the destination register of the first (div/sqrt). * Do not insert NOPs if one of the floating point operations is a (div/sqrt). * Insert NOPs to prevent (div/sqrt) followed by a branch.
99 lines
2.8 KiB
TableGen
99 lines
2.8 KiB
TableGen
//===-- LeonFeatures.td - Describe the Leon Features -------*- tablegen -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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//
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//===----------------------------------------------------------------------===//
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//===----------------------------------------------------------------------===//
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// UMAC and SMAC support for LEON3 and LEON4 processors.
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//===----------------------------------------------------------------------===//
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//support to casa instruction; for leon3 subtarget only
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def UMACSMACSupport : SubtargetFeature<
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"hasumacsmac",
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"HasUmacSmac",
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"true",
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"Enable UMAC and SMAC for LEON3 and LEON4 processors"
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>;
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//===----------------------------------------------------------------------===//
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// CASA Support differs between LEON3-FT GR712RC and LEON3-FT UT699
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// We need to have the option to switch this on and off.
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//===----------------------------------------------------------------------===//
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//support to casa instruction; for leon3 subtarget only
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def LeonCASA : SubtargetFeature<
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"hasleoncasa",
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"HasLeonCasa",
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"true",
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"Enable CASA instruction for LEON3 and LEON4 processors"
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>;
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def InsertNOPLoad: SubtargetFeature<
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"insertnopload",
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"InsertNOPLoad",
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"true",
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"LEON3 erratum fix: Insert a NOP instruction after every single-cycle load instruction when the next instruction is another load/store instruction"
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>;
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def DetectRoundChange : SubtargetFeature<
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"detectroundchange",
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"DetectRoundChange",
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"true",
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"LEON3 erratum detection: Detects any rounding mode change "
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"request: use only the round-to-nearest rounding mode"
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>;
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def FixAllFDIVSQRT : SubtargetFeature<
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"fixallfdivsqrt",
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"FixAllFDIVSQRT",
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"true",
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"LEON erratum fix: Fix FDIVS/FDIVD/FSQRTS/FSQRTD instructions with NOPs and floating-point store"
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>;
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def LeonCycleCounter
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: SubtargetFeature<"leoncyclecounter", "HasLeonCycleCounter", "true",
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"Use the Leon cycle counter register">;
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def FixTN0009 : SubtargetFeature<
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"fix-tn0009",
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"FixTN0009",
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"true",
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"Enable workaround for errata described in GRLIB-TN-0009"
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>;
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def FixTN0010 : SubtargetFeature<
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"fix-tn0010",
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"FixTN0010",
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"true",
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"Enable workaround for errata described in GRLIB-TN-0010"
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>;
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def FixTN0011 : SubtargetFeature<
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"fix-tn0011",
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"FixTN0011",
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"true",
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"Enable workaround for errata described in GRLIB-TN-0011"
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>;
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def FixTN0012 : SubtargetFeature<
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"fix-tn0012",
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"FixTN0012",
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"true",
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"Enable workaround for errata described in GRLIB-TN-0012"
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>;
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def FixTN0013 : SubtargetFeature<
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"fix-tn0013",
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"FixTN0013",
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"true",
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"Enable workaround for errata described in GRLIB-TN-0013"
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>;
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