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-rw-r--r--contrib/llvm/lib/Target/SystemZ/SystemZTargetMachine.cpp108
1 files changed, 108 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/SystemZ/SystemZTargetMachine.cpp b/contrib/llvm/lib/Target/SystemZ/SystemZTargetMachine.cpp
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index 000000000000..dee92e960c54
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+++ b/contrib/llvm/lib/Target/SystemZ/SystemZTargetMachine.cpp
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+//===-- SystemZTargetMachine.cpp - Define TargetMachine for SystemZ -------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "SystemZTargetMachine.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/Transforms/Scalar.h"
+
+using namespace llvm;
+
+extern "C" void LLVMInitializeSystemZTarget() {
+ // Register the target.
+ RegisterTargetMachine<SystemZTargetMachine> X(TheSystemZTarget);
+}
+
+SystemZTargetMachine::SystemZTargetMachine(const Target &T, StringRef TT,
+ StringRef CPU, StringRef FS,
+ const TargetOptions &Options,
+ Reloc::Model RM,
+ CodeModel::Model CM,
+ CodeGenOpt::Level OL)
+ : LLVMTargetMachine(T, TT, CPU, FS, Options, RM, CM, OL),
+ Subtarget(TT, CPU, FS),
+ // Make sure that global data has at least 16 bits of alignment by default,
+ // so that we can refer to it using LARL. We don't have any special
+ // requirements for stack variables though.
+ DL("E-p:64:64:64-i1:8:16-i8:8:16-i16:16-i32:32-i64:64"
+ "-f32:32-f64:64-f128:64-a0:8:16-n32:64"),
+ InstrInfo(*this), TLInfo(*this), TSInfo(*this),
+ FrameLowering(*this, Subtarget) {
+ initAsmInfo();
+}
+
+namespace {
+/// SystemZ Code Generator Pass Configuration Options.
+class SystemZPassConfig : public TargetPassConfig {
+public:
+ SystemZPassConfig(SystemZTargetMachine *TM, PassManagerBase &PM)
+ : TargetPassConfig(TM, PM) {}
+
+ SystemZTargetMachine &getSystemZTargetMachine() const {
+ return getTM<SystemZTargetMachine>();
+ }
+
+ virtual void addIRPasses() LLVM_OVERRIDE;
+ virtual bool addInstSelector() LLVM_OVERRIDE;
+ virtual bool addPreSched2() LLVM_OVERRIDE;
+ virtual bool addPreEmitPass() LLVM_OVERRIDE;
+};
+} // end anonymous namespace
+
+void SystemZPassConfig::addIRPasses() {
+ TargetPassConfig::addIRPasses();
+ addPass(createPartiallyInlineLibCallsPass());
+}
+
+bool SystemZPassConfig::addInstSelector() {
+ addPass(createSystemZISelDag(getSystemZTargetMachine(), getOptLevel()));
+ return false;
+}
+
+bool SystemZPassConfig::addPreSched2() {
+ if (getSystemZTargetMachine().getSubtargetImpl()->hasLoadStoreOnCond())
+ addPass(&IfConverterID);
+ return true;
+}
+
+bool SystemZPassConfig::addPreEmitPass() {
+ // We eliminate comparisons here rather than earlier because some
+ // transformations can change the set of available CC values and we
+ // generally want those transformations to have priority. This is
+ // especially true in the commonest case where the result of the comparison
+ // is used by a single in-range branch instruction, since we will then
+ // be able to fuse the compare and the branch instead.
+ //
+ // For example, two-address NILF can sometimes be converted into
+ // three-address RISBLG. NILF produces a CC value that indicates whether
+ // the low word is zero, but RISBLG does not modify CC at all. On the
+ // other hand, 64-bit ANDs like NILL can sometimes be converted to RISBG.
+ // The CC value produced by NILL isn't useful for our purposes, but the
+ // value produced by RISBG can be used for any comparison with zero
+ // (not just equality). So there are some transformations that lose
+ // CC values (while still being worthwhile) and others that happen to make
+ // the CC result more useful than it was originally.
+ //
+ // Another reason is that we only want to use BRANCH ON COUNT in cases
+ // where we know that the count register is not going to be spilled.
+ //
+ // Doing it so late makes it more likely that a register will be reused
+ // between the comparison and the branch, but it isn't clear whether
+ // preventing that would be a win or not.
+ if (getOptLevel() != CodeGenOpt::None)
+ addPass(createSystemZElimComparePass(getSystemZTargetMachine()));
+ if (getOptLevel() != CodeGenOpt::None)
+ addPass(createSystemZShortenInstPass(getSystemZTargetMachine()));
+ addPass(createSystemZLongBranchPass(getSystemZTargetMachine()));
+ return true;
+}
+
+TargetPassConfig *SystemZTargetMachine::createPassConfig(PassManagerBase &PM) {
+ return new SystemZPassConfig(this, PM);
+}