From 52c08fdb906cbdaa10cb5f46351ebc777debf292 Mon Sep 17 00:00:00 2001 From: Bob Wilson Date: Wed, 1 Oct 2014 22:44:01 +0000 Subject: [PATCH] PR21101: tablegen's FastISel emitter should filter out unused functions. FastISel has a fixed set of virtual functions that are overridden by the tablegen-generated code for each target. These functions are distinguished by the kinds of operands, e.g., register + immediate = "ri". The FastISel emitter has been blindly emitting functions with different combinations of operand kinds, even for combinations that are completely unused by FastISel, e.g., "fastEmit_rrr". Change to filter out functions that will be irrelevant for FastISel and do not bother generating the code for them. Also add explicit "override" keywords for the virtual functions that are overridden. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218838 91177308-0d34-0410-b5e6-96231b3b80d8 --- utils/TableGen/FastISelEmitter.cpp | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/utils/TableGen/FastISelEmitter.cpp b/utils/TableGen/FastISelEmitter.cpp index 12be6a63bd3..675207d2362 100644 --- a/utils/TableGen/FastISelEmitter.cpp +++ b/utils/TableGen/FastISelEmitter.cpp @@ -19,6 +19,7 @@ #include "CodeGenDAGPatterns.h" #include "llvm/ADT/SmallString.h" +#include "llvm/ADT/StringSwitch.h" #include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/TableGen/Error.h" @@ -541,6 +542,17 @@ void FastISelMap::collectPatterns(CodeGenDAGPatterns &CGP) { continue; } + // Check if the operands match one of the patterns handled by FastISel. + std::string ManglingSuffix; + raw_string_ostream SuffixOS(ManglingSuffix); + Operands.PrintManglingSuffix(SuffixOS, ImmediatePredicates, true); + SuffixOS.flush(); + if (!StringSwitch(ManglingSuffix) + .Cases("", "r", "rr", "ri", "rf", true) + .Cases("rri", "i", "f", true) + .Default(false)) + continue; + // Get the predicate that guards this pattern. std::string PredicateCheck = Pattern.getPredicateCheck(); @@ -803,7 +815,10 @@ void FastISelMap::printFunctionDefinitions(raw_ostream &OS) { if (!Operands.empty()) OS << ", "; Operands.PrintParameters(OS); - OS << ") {\n"; + OS << ") "; + if (!Operands.hasAnyImmediateCodes()) + OS << "override "; + OS << "{\n"; // If there are any forms of this signature available that operate on // constrained forms of the immediate (e.g., 32-bit sext immediate in a -- 2.34.1