[PGO] Enable clang to pass compiler-rt profile support library to linker on Windows

[slingn]

Summary

This change enables clang to automatically link binaries built with the -fprofile-instr-generate against the clang_rt.profile-i386.lib library.

[davidxl]

need a test case in test/Driver/instrprof-ld.c

[slingn]

Updated for davidxl's comments:

-Added test for linker flag in test/Driver/instrprof-ld.c

[davidxl]

test/Driver/instrprof-ld.c

119

Is this check necessary?

[davidxl]

I meant the first line that checks the linker.

David

[slingn]

-Fix instrprof-ld.c test to correctly skip to linker input.

test/Driver/instrprof-ld.c

119

Ah - that wasn't doing quite what I wanted. Similar to the other tests we want to skip to the point where the linker args are given. Fixed.

[davidxl]

test/Driver/instrprof-ld.c

114

Can the linker be 'lld-link.exe'?

[slingn]

-Fixed to accept any linker with name ending in 'link(.exe)?'

[davidxl]

lgtm

lib/Driver/Tools.cpp

if (A.getOption().matches(options::OPT_l)) {
       continue;
     }
 
     // Otherwise, this is some other kind of linker input option like -Wl, -z,
     // or -L. Render it, even if MSVC doesn't understand it.
     A.renderAsInput(Args, CmdArgs);
   }
 
+  TC.addProfileRTLibs(Args, CmdArgs);
+
   // We need to special case some linker paths.  In the case of lld, we need to
   // translate 'lld' into 'lld-link', and in the case of the regular msvc
   // linker, we need to use a special search algorithm.
   llvm::SmallString<128> linkPath;
   StringRef Linker = Args.getLastArgValue(options::OPT_fuse_ld_EQ, "link");
   if (Linker.equals_lower("lld"))
     Linker = "lld-link";
 

test/Driver/instrprof-ld.c

 //
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     -target armv7s-apple-darwin10 -mwatchos-version-min=2.0 -arch armv7k -fprofile-instr-generate \
 // RUN:     -resource-dir=%S/Inputs/resource_dir \
 // RUN:   | FileCheck --check-prefix=CHECK-WATCHOS-ARMV7 %s
 //
 // CHECK-WATCHOS-ARMV7: "{{(.*[^-.0-9A-Z_a-z])?}}ld{{(.exe)?}}"
 // CHECK-WATCHOS-ARMV7: "{{.*}}/Inputs/resource_dir{{/|\\\\}}lib{{/|\\\\}}darwin{{/|\\\\}}libclang_rt.profile_watchos.a"
+//
+// RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
+// RUN:     -target i386-pc-win32 -fprofile-instr-generate \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:   | FileCheck --check-prefix=CHECK-WINDOWS-I386 %s
+//
+// CHECK-WINDOWS-I386: "{{.*}}link{{(.exe)?}}"
+// CHECK-WINDOWS-I386: "{{.*}}clang_rt.profile-i386.lib"
+//
+// RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
+// RUN:     -target x86_64-pc-win32 -fprofile-instr-generate \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:   | FileCheck --check-prefix=CHECK-WINDOWS-X86-64 %s
+//
+// CHECK-WINDOWS-X86-64: "{{.*}}link{{(.exe)?}}"
+// CHECK-WINDOWS-X86-64: "{{.*}}clang_rt.profile-x86_64.lib"