[AArch64] Implement Clang CLI interface proposal about "-march".
1. Revert "Add default feature for CPUs on AArch64 target in Clang"
at r210625. Then, all enabled feature will by passed explicitly by
-target-feature in -cc1 option.
2. Get "-mfpu" deprecated.
3. Implement support of "-march". Usage is:
-march=armv8-a+[no]feature
For instance, "-march=armv8-a+neon+crc+nocrypto". Here "armv8-a" is
necessary, and CPU names are not acceptable. Candidate features are
fp, neon, crc and crypto. Where conflicting feature modifiers are
specified, the right-most feature is used.
4. Implement support of "-mtune". Usage is:
-march=CPU_NAME
For instance, "-march=cortex-a57". This option will ONLY get
micro-architectural feature enabled specifying to target CPU,
like "+zcm" and "+zcz" for cyclone. Any architectural features
WON'T be modified.
5. Change usage of "-mcpu" to "-mcpu=CPU_NAME+[no]feature", which is
an alias to "-march={feature of CPU_NAME}+[no]feature" and
"-mtune=CPU_NAME" together. Where this option is used in conjunction
with -march or -mtune, those options take precedence over the
appropriate part of this option.
llvm-svn: 213353
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index e5db2f0..d436ce6 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -488,29 +488,6 @@
}
}
-// Handle -mfpu=.
-//
-// FIXME: Centralize feature selection, defaulting shouldn't be also in the
-// frontend target.
-static void getAArch64FPUFeatures(const Driver &D, const Arg *A,
- const ArgList &Args,
- std::vector<const char *> &Features) {
- StringRef FPU = A->getValue();
- if (FPU == "fp-armv8") {
- Features.push_back("+fp-armv8");
- } else if (FPU == "neon-fp-armv8") {
- Features.push_back("+fp-armv8");
- Features.push_back("+neon");
- } else if (FPU == "crypto-neon-fp-armv8") {
- Features.push_back("+fp-armv8");
- Features.push_back("+neon");
- Features.push_back("+crypto");
- } else if (FPU == "neon") {
- Features.push_back("+neon");
- } else
- D.Diag(diag::err_drv_clang_unsupported) << A->getAsString(Args);
-}
-
// Handle -mhwdiv=.
static void getARMHWDivFeatures(const Driver &D, const Arg *A,
const ArgList &Args,
@@ -849,18 +826,21 @@
/// getAArch64TargetCPU - Get the (LLVM) name of the AArch64 cpu we are
/// targeting.
static std::string getAArch64TargetCPU(const ArgList &Args) {
- // If we have -mcpu=, use that.
- if (Arg *A = Args.getLastArg(options::OPT_mcpu_EQ)) {
- StringRef MCPU = A->getValue();
- // Handle -mcpu=native.
- if (MCPU == "native")
- return llvm::sys::getHostCPUName();
- else
- return MCPU;
+ Arg *A;
+ std::string CPU;
+ // If we have -mtune or -mcpu, use that.
+ if ((A = Args.getLastArg(options::OPT_mtune_EQ))) {
+ CPU = A->getValue();
+ } else if ((A = Args.getLastArg(options::OPT_mcpu_EQ))) {
+ StringRef Mcpu = A->getValue();
+ CPU = Mcpu.split("+").first;
}
- // At some point, we may need to check -march here, but for now we only
- // one arm64 architecture.
+ // Handle CPU name is 'native'.
+ if (CPU == "native")
+ return llvm::sys::getHostCPUName();
+ else if (CPU.size())
+ return CPU;
// Make sure we pick "cyclone" if -arch is used.
// FIXME: Should this be picked by checking the target triple instead?
@@ -895,9 +875,6 @@
CmdArgs.push_back("-target-abi");
CmdArgs.push_back(ABIName);
- CmdArgs.push_back("-target-cpu");
- CmdArgs.push_back(Args.MakeArgString(getAArch64TargetCPU(Args)));
-
if (Args.hasArg(options::OPT_mstrict_align)) {
CmdArgs.push_back("-backend-option");
CmdArgs.push_back("-aarch64-strict-align");
@@ -1610,13 +1587,126 @@
CmdArgs.push_back ("-machine-sink-split=0");
}
+// Decode AArch64 features from string like +[no]featureA+[no]featureB+...
+static bool DecodeAArch64Features(const Driver &D, const StringRef &text,
+ std::vector<const char *> &Features) {
+ SmallVector<StringRef, 8> Split;
+ text.split(Split, StringRef("+"), -1, false);
+
+ for (unsigned I = 0, E = Split.size(); I != E; ++I) {
+ const char *result = llvm::StringSwitch<const char *>(Split[I])
+ .Case("fp", "+fp-armv8")
+ .Case("simd", "+neon")
+ .Case("crc", "+crc")
+ .Case("crypto", "+crypto")
+ .Case("nofp", "-fp-armv8")
+ .Case("nosimd", "-neon")
+ .Case("nocrc", "-crc")
+ .Case("nocrypto", "-crypto")
+ .Default(nullptr);
+ if (result)
+ Features.push_back(result);
+ else if (Split[I] == "neon" || Split[I] == "noneon")
+ D.Diag(diag::err_drv_no_neon_modifier);
+ else
+ return false;
+ }
+ return true;
+}
+
+// Check if the CPU name and feature modifiers in -mcpu are legal. If yes,
+// decode CPU and feature.
+static bool DecodeAArch64Mcpu(const Driver &D, StringRef Mcpu, StringRef &CPU,
+ std::vector<const char *> &Features) {
+ std::pair<StringRef, StringRef> Split = Mcpu.split("+");
+ CPU = Split.first;
+ if (CPU == "cyclone" || CPU == "cortex-a53" || CPU == "cortex-a57") {
+ Features.push_back("+neon");
+ Features.push_back("+crc");
+ Features.push_back("+crypto");
+ } else if (CPU == "generic") {
+ Features.push_back("+neon");
+ } else {
+ return false;
+ }
+
+ if (Split.second.size() && !DecodeAArch64Features(D, Split.second, Features))
+ return false;
+
+ return true;
+}
+
+static bool
+getAArch64ArchFeaturesFromMarch(const Driver &D, StringRef March,
+ const ArgList &Args,
+ std::vector<const char *> &Features) {
+ std::pair<StringRef, StringRef> Split = March.split("+");
+ if (Split.first != "armv8-a")
+ return false;
+
+ if (Split.second.size() && !DecodeAArch64Features(D, Split.second, Features))
+ return false;
+
+ return true;
+}
+
+static bool
+getAArch64ArchFeaturesFromMcpu(const Driver &D, StringRef Mcpu,
+ const ArgList &Args,
+ std::vector<const char *> &Features) {
+ StringRef CPU;
+ if (!DecodeAArch64Mcpu(D, Mcpu, CPU, Features))
+ return false;
+
+ return true;
+}
+
+static bool
+getAArch64MicroArchFeaturesFromMtune(const Driver &D, StringRef Mtune,
+ const ArgList &Args,
+ std::vector<const char *> &Features) {
+ // Handle CPU name is 'native'.
+ if (Mtune == "native")
+ Mtune = llvm::sys::getHostCPUName();
+ if (Mtune == "cyclone") {
+ Features.push_back("+zcm");
+ Features.push_back("+zcz");
+ }
+ return true;
+}
+
+static bool
+getAArch64MicroArchFeaturesFromMcpu(const Driver &D, StringRef Mcpu,
+ const ArgList &Args,
+ std::vector<const char *> &Features) {
+ StringRef CPU;
+ std::vector<const char *> DecodedFeature;
+ if (!DecodeAArch64Mcpu(D, Mcpu, CPU, DecodedFeature))
+ return false;
+
+ return getAArch64MicroArchFeaturesFromMtune(D, CPU, Args, Features);
+}
+
static void getAArch64TargetFeatures(const Driver &D, const ArgList &Args,
std::vector<const char *> &Features) {
- // Honor -mfpu=.
- if (const Arg *A = Args.getLastArg(options::OPT_mfpu_EQ))
- getAArch64FPUFeatures(D, A, Args, Features);
- else
- Features.push_back("+neon");
+ Arg *A;
+ bool success = true;
+ // Enable NEON by default.
+ Features.push_back("+neon");
+ if ((A = Args.getLastArg(options::OPT_march_EQ)))
+ success = getAArch64ArchFeaturesFromMarch(D, A->getValue(), Args, Features);
+ else if ((A = Args.getLastArg(options::OPT_mcpu_EQ)))
+ success = getAArch64ArchFeaturesFromMcpu(D, A->getValue(), Args, Features);
+
+ if (success && (A = Args.getLastArg(options::OPT_mtune_EQ)))
+ success =
+ getAArch64MicroArchFeaturesFromMtune(D, A->getValue(), Args, Features);
+ else if (success && (A = Args.getLastArg(options::OPT_mcpu_EQ)))
+ success =
+ getAArch64MicroArchFeaturesFromMcpu(D, A->getValue(), Args, Features);
+
+ if (!success)
+ D.Diag(diag::err_drv_clang_unsupported) << A->getAsString(Args);
if (Args.getLastArg(options::OPT_mgeneral_regs_only)) {
Features.push_back("-fp-armv8");