[PowerPC] Restrict various P10 options to P10 only.

[amyk]

Summary

This patch attempts to restrict the following P10 options:

-mprefixed
-mpcrel
-mpaired-vector-memops

To P10 only. This will prevent the use of these options on P9 and earlier.

The behaviour of this patch looks like the following on pre-P10:

$ clang -mcpu=pwr9 -mpaired-vector-memops test.c -o test
error: option '-mpaired-vector-memops' cannot be specified without '-mcpu=pwr10'

$ clang -mcpu=pwr9 -mprefixed test.c -o test
error: option '-mprefixed' cannot be specified without '-mcpu=pwr10'

$ clang -mcpu=pwr9 -mprefixed -mpcrel test.c -o test
error: option '-mpcrel' cannot be specified without '-mcpu=pwr10 -mprefixed'

$ clang -mcpu=pwr9 -mpcrel -mprefixed test.c -o test
error: option '-mpcrel' cannot be specified without '-mcpu=pwr10 -mprefixed'

$ clang -mcpu=pwr9 -mpcrel test.c -o test
error: option '-mpcrel' cannot be specified without '-mcpu=pwr10 -mprefixed'

[Conanap]

LGTM

[lei]

clang/lib/Basic/Targets/PPC.cpp

585–588

I think this need more thought:

$ clang -mcpu=pwr9 -mprefixed -mpcrel test.c -o test
error: option '-mpcrel' cannot be specified without '-mprefixed'
error: option '-mprefixed' cannot be specified without '-mcpu=pwr10'

$ clang -mcpu=pwr9 -mpcrel test.c -o test
error: option '-mpcrel' cannot be specified without '-mprefixed'

For this, the first err makes not sense since both -mprefixed and -mpcrel is specified:

$ clang -mcpu=pwr9 -mprefixed -mpcrel test.c -o test
error: option '-mpcrel' cannot be specified without '-mprefixed'
error: option '-mprefixed' cannot be specified without '-mcpu=pwr10'

Shouldn't it just give:

$ clang -mcpu=pwr9 -mprefixed -mpcrel test.c -o test
error: option '-mpcrel' cannot be specified without '-mcpu=pwr10 -mprefixed'

For this:

$ clang -mcpu=pwr9 -mpcrel test.c -o test
error: option '-mpcrel' cannot be specified without '-mprefixed'

I think it's better if it says:

$ clang -mcpu=pwr9 -mpcrel test.c -o test
error: option '-mpcrel' cannot be specified without '-mcpu=pwr10 -mprefixed'

[amyk]

Addressed Lei's review comments to output:

error: option '-mpcrel' cannot be specified without '-mcpu=pwr10 -mprefixed'

when PC-Rel is specified pre-P10.

Also updated the comment for MMA on pre-P10 so it makes more sense and is more consistent with the comments I've added.

[amyk]

Ping.

[amyk]

Ping @lei.

[lei]

LGTM
I think you went a bit overkill with the tests for this patch 🙂. Please cut down the number of run lines before committing.

clang/test/Driver/ppc-p10-features-support-check.c

5

I think you can just use pwr10 and power10 in diff run lines if you need, but no need to test for both in this case.

12

might be an overkill to also test for pwr7/8. I think pwr9/10 test is enough.

20

same comment for the set of runlines below.

clang/lib/Basic/Targets/PPC.cpp

bool PPCTargetInfo::initFeatureMap(
 
   if (!(ArchDefs & ArchDefinePwr9) && (ArchDefs & ArchDefinePpcgr) &&
       llvm::is_contained(FeaturesVec, "+float128")) {
     // We have __float128 on PPC but not power 9 and above.
     Diags.Report(diag::err_opt_not_valid_with_opt) << "-mfloat128" << CPU;
     return false;
   }
 
-  if (!(ArchDefs & ArchDefinePwr10) &&
-      llvm::is_contained(FeaturesVec, "+mma")) {
-    // We have MMA on PPC but not power 10 and above.
+  if (!(ArchDefs & ArchDefinePwr10)) {
+    if (llvm::find(FeaturesVec, "+mma") != FeaturesVec.end()) {
+      // MMA operations are not available pre-Power10.
       Diags.Report(diag::err_opt_not_valid_with_opt) << "-mmma" << CPU;
       return false;
     }
+    if (llvm::find(FeaturesVec, "+pcrel") != FeaturesVec.end()) {
+      // PC-Relative instructions are not available pre-Power10,
+      // and these instructions also require prefixed instructions support.
+      Diags.Report(diag::err_opt_not_valid_without_opt)
+          << "-mpcrel"
+          << "-mcpu=pwr10 -mprefixed";
+      return false;
+    }
+    if (llvm::find(FeaturesVec, "+prefixed") != FeaturesVec.end()) {
+      // Prefixed instructions are not available pre-Power10.
+      Diags.Report(diag::err_opt_not_valid_without_opt) << "-mprefixed"
+                                                        << "-mcpu=pwr10";
+      return false;
+    }
+    if (llvm::find(FeaturesVec, "+paired-vector-memops") != FeaturesVec.end()) {
+      // Paired vector memops are not available pre-Power10.
+      Diags.Report(diag::err_opt_not_valid_without_opt)
+          << "-mpaired-vector-memops"
+          << "-mcpu=pwr10";
+      return false;
+    }
+  }
 
   if (!(ArchDefs & ArchDefinePwr8) &&
       llvm::is_contained(FeaturesVec, "+rop-protect")) {
     // We can turn on ROP Protect on Power 8 and above.
     Diags.Report(diag::err_opt_not_valid_with_opt) << "-mrop-protect" << CPU;
     return false;
   }
 

clang/test/Driver/ppc-p10-features-support-check.c

+// RUN: %clang -target powerpc64le-unknown-linux-gnu -S -emit-llvm  \
+// RUN:   -mcpu=pwr10 -mpaired-vector-memops %s -o - | FileCheck %s \
+// RUN:   --check-prefix=HASPAIRED
+// RUN: not %clang -target powerpc64le-unknown-linux-gnu -fsyntax-only \
+// RUN:   -mcpu=pwr9 -mpaired-vector-memops %s 2>&1 | FileCheck %s \
+// RUN:   --check-prefix=NOPAIRED
+// RUN: not %clang -target powerpc64le-unknown-linux-gnu -fsyntax-only \
+// RUN:   -mpaired-vector-memops %s 2>&1 | FileCheck %s \
+// RUN:   --check-prefix=NOPAIRED
+
+// RUN: %clang -target powerpc64le-unknown-linux-gnu -S -emit-llvm  \
+// RUN:   -mcpu=pwr10 -mprefixed %s -o - | FileCheck %s \
+// RUN:   --check-prefix=HASPREFIXED
+// RUN: not %clang -target powerpc64le-unknown-linux-gnu -fsyntax-only \
+// RUN:   -mcpu=pwr9 -mprefixed %s 2>&1 | FileCheck %s \
+// RUN:   --check-prefix=NOPREFIXED
+// RUN: not %clang -target powerpc64le-unknown-linux-gnu -fsyntax-only \
+// RUN:   -mprefixed %s 2>&1 | FileCheck %s \
+// RUN:   --check-prefix=NOPREFIXED
+
+// RUN: %clang -target powerpc64le-unknown-linux-gnu -S -emit-llvm  \
+// RUN:   -mcpu=pwr10 -mpcrel %s -o - | FileCheck %s \
+// RUN:   --check-prefix=HASPCREL
+// RUN: not %clang -target powerpc64le-unknown-linux-gnu -fsyntax-only \
+// RUN:   -mcpu=pwr9 -mpcrel %s 2>&1 | FileCheck %s \
+// RUN:   --check-prefix=NOPCREL
+// RUN: not %clang -target powerpc64le-unknown-linux-gnu -fsyntax-only \
+// RUN:   -mpcrel %s 2>&1 | FileCheck %s \
+// RUN:   --check-prefix=NOPCREL
+
+// RUN: %clang -target powerpc64le-unknown-linux-gnu -S -emit-llvm  \
+// RUN:   -mcpu=pwr10 -mpcrel -mprefixed %s -o - | FileCheck %s \
+// RUN:   --check-prefix=HASPCREL-PREFIX
+// RUN: not %clang -target powerpc64le-unknown-linux-gnu -fsyntax-only \
+// RUN:   -mcpu=pwr9 -mpcrel -mprefixed %s 2>&1 | FileCheck %s \
+// RUN:   --check-prefix=NOPCREL-PREFIX
+// RUN: not %clang -target powerpc64le-unknown-linux-gnu -fsyntax-only \
+// RUN:   -mpcrel -mprefixed %s 2>&1 | FileCheck %s \
+// RUN:   --check-prefix=NOPCREL-PREFIX
+
+int test_p10_features() {
+  return 0;
+}
+
+// HASPAIRED: test_p10_features() #0 {
+// HASPAIRED: attributes #0 = {
+// HASPAIRED-SAME: +paired-vector-memops
+// NOPAIRED: option '-mpaired-vector-memops' cannot be specified without '-mcpu=pwr10'
+
+// HASPREFIXED: test_p10_features() #0 {
+// HASPREFIXED: attributes #0 = {
+// HASPREFIXED-SAME: +prefix-instrs
+// NOPREFIXED: option '-mprefixed' cannot be specified without '-mcpu=pwr10'
+
+// HASPCREL: test_p10_features() #0 {
+// HASPCREL: attributes #0 = {
+// HASPCREL-SAME: +pcrelative-memops
+// NOPCREL: option '-mpcrel' cannot be specified without '-mcpu=pwr10 -mprefixed'
+
+// HASPCREL-PREFIX: test_p10_features() #0 {
+// HASPCREL-PREFIX: attributes #0 = {
+// HASPCREL-PREFIX-SAME: +pcrelative-memops
+// HASPCREL-PREFIX-SAME: +prefix-instrs
+// NOPCREL-PREFIX: option '-mpcrel' cannot be specified without '-mcpu=pwr10 -mprefixed'
+