[clang] 157cd93 - [clang] Disallow fbasic-block-sections on non-ELF, non-x86 targets.

[Snehasish Kumar via cfe-commits]

Author: Snehasish Kumar
Date: 2020-09-10T00:15:33-07:00
New Revision: 157cd93b48a90f484e9eb2ed9997e0372b9c7ebb

URL: https://github.com/llvm/llvm-project/commit/157cd93b48a90f484e9eb2ed9997e0372b9c7ebb
DIFF: https://github.com/llvm/llvm-project/commit/157cd93b48a90f484e9eb2ed9997e0372b9c7ebb.diff

LOG: [clang] Disallow fbasic-block-sections on non-ELF, non-x86 targets.

Basic block sections is untested on other platforms and binary formats apart
from x86,elf. This patch emits a warning and drops the flag if the platform
and binary format are not compatible. Add a test to ensure that
specifying an incompatible target in the driver does not enable the
feature.

Differential Revision: https://reviews.llvm.org/D87426

Added: 
    

Modified: 
    clang/lib/Driver/ToolChains/Clang.cpp
    clang/test/Driver/fbasic-block-sections.c

Removed: 
    


################################################################################
diff  --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index 1680f2ad91ea..40659ebb1395 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -4880,13 +4880,18 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   }
 
   if (Arg *A = Args.getLastArg(options::OPT_fbasic_block_sections_EQ)) {
-    StringRef Val = A->getValue();
-    if (Val != "all" && Val != "labels" && Val != "none" &&
-        !(Val.startswith("list=") && llvm::sys::fs::exists(Val.substr(5))))
-      D.Diag(diag::err_drv_invalid_value)
-          << A->getAsString(Args) << A->getValue();
-    else
-      A->render(Args, CmdArgs);
+    if (Triple.isX86() && Triple.isOSBinFormatELF()) {
+      StringRef Val = A->getValue();
+      if (Val != "all" && Val != "labels" && Val != "none" &&
+          !(Val.startswith("list=") && llvm::sys::fs::exists(Val.substr(5))))
+        D.Diag(diag::err_drv_invalid_value)
+            << A->getAsString(Args) << A->getValue();
+      else
+        A->render(Args, CmdArgs);
+    } else {
+      D.Diag(diag::err_drv_unsupported_opt_for_target)
+          << A->getAsString(Args) << TripleStr;
+    }
   }
 
   if (Args.hasFlag(options::OPT_fdata_sections, options::OPT_fno_data_sections,

diff  --git a/clang/test/Driver/fbasic-block-sections.c b/clang/test/Driver/fbasic-block-sections.c
index 2ff98c94222b..93c7fe9fc069 100644
--- a/clang/test/Driver/fbasic-block-sections.c
+++ b/clang/test/Driver/fbasic-block-sections.c
@@ -1,9 +1,12 @@
-// RUN: %clang -### -fbasic-block-sections=none %s -S 2>&1 | FileCheck -check-prefix=CHECK-OPT-NONE %s
-// RUN: %clang -### -fbasic-block-sections=all %s -S 2>&1 | FileCheck -check-prefix=CHECK-OPT-ALL %s
-// RUN: %clang -### -fbasic-block-sections=list=%s %s -S 2>&1 | FileCheck -check-prefix=CHECK-OPT-LIST %s
-// RUN: %clang -### -fbasic-block-sections=labels %s -S 2>&1 | FileCheck -check-prefix=CHECK-OPT-LABELS %s
+// RUN: %clang -### -target x86_64 -fbasic-block-sections=none %s -S 2>&1 | FileCheck -check-prefix=CHECK-OPT-NONE %s
+// RUN: %clang -### -target x86_64 -fbasic-block-sections=all %s -S 2>&1 | FileCheck -check-prefix=CHECK-OPT-ALL %s
+// RUN: %clang -### -target x86_64 -fbasic-block-sections=list=%s %s -S 2>&1 | FileCheck -check-prefix=CHECK-OPT-LIST %s
+// RUN: %clang -### -target x86_64 -fbasic-block-sections=labels %s -S 2>&1 | FileCheck -check-prefix=CHECK-OPT-LABELS %s
+// RUN: not %clang -c -target arm-unknown-linux -fbasic-block-sections=all %s -S 2>&1 | FileCheck -check-prefix=CHECK-TRIPLE %s
+// RUN: not %clang -c -target x86_64-apple-darwin10 -fbasic-block-sections=all %s -S 2>&1 | FileCheck -check-prefix=CHECK-TRIPLE %s
 //
-// CHECK-OPT-NONE: "-fbasic-block-sections=none"
-// CHECK-OPT-ALL: "-fbasic-block-sections=all"
-// CHECK-OPT-LIST: "-fbasic-block-sections={{[^ ]*}}fbasic-block-sections.c"
+// CHECK-OPT-NONE:   "-fbasic-block-sections=none"
+// CHECK-OPT-ALL:    "-fbasic-block-sections=all"
+// CHECK-OPT-LIST:   "-fbasic-block-sections={{[^ ]*}}fbasic-block-sections.c"
 // CHECK-OPT-LABELS: "-fbasic-block-sections=labels"
+// CHECK-TRIPLE:     error: unsupported option '-fbasic-block-sections=all' for target