[clang] [PS5] Enable support for DTLTO in the PS5 Clang driver (PR #158041)

[Jeremy Morse via cfe-commits]

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@@ -0,0 +1,45 @@
+// REQUIRES: lld
+
+/// Check DTLTO options are forwarded to the linker.
+
+/// Check that options are forwarded as expected with --thinlto-distributor=.
+// RUN: %clang -flto=thin %s -### --target=x86_64-sie-ps5 \
+// RUN:   -Xthinlto-distributor=a1 -Xthinlto-distributor=a2,a3 \
+// RUN:   -fthinlto-distributor=d.exe -Werror 2>&1 | \
+// RUN:   FileCheck %s --check-prefix=FORWARD
+
+// FORWARD: prospero-lld
+// FORWARD-SAME: "--thinlto-distributor=d.exe"
+// FORWARD-SAME: "--thinlto-remote-compiler={{[^"]+}}"
+// FORWARD-SAME: "--thinlto-distributor-arg=a1"
+// FORWARD-SAME: "--thinlto-distributor-arg=a2"
+// FORWARD-SAME: "--thinlto-distributor-arg=a3"
+
+/// Check that options are not added without --thinlto-distributor= and
+/// that a warning is issued for unused -Xthinlto-distributor options.
+// RUN: %clang -flto=thin %s -### --target=x86_64-sie-ps5 \
+// RUN:   -Xthinlto-distributor=a1 -Xthinlto-distributor=a2,a3 2>&1 | \
+// RUN:   FileCheck %s --check-prefix=NODIST --implicit-check-not=distributor \
+// RUN:     --implicit-check-not=remote-compiler
+
+// NODIST: warning: argument unused during compilation: '-Xthinlto-distributor=a1'
+// NODIST: warning: argument unused during compilation: '-Xthinlto-distributor=a2,a3'
+// NODIST: prospero-lld
+
+/// Check the expected arguments are forwarded by default with only
+/// --thinlto-distributor=.
+// RUN: %clang -flto=thin %s -### --target=x86_64-sie-ps5 \
+// RUN:   -fthinlto-distributor=d.exe -Werror 2>&1 | \
+// RUN:   FileCheck %s --check-prefix=DEFAULT --implicit-check-not=distributor \
+// RUN:     --implicit-check-not=remote-compiler
+
+// DEFAULT: prospero-lld
+// DEFAULT-SAME: "--thinlto-distributor=d.exe"
+// DEFAULT-SAME: "--thinlto-remote-compiler={{.*}}clang{{[^\"]*}}"
+
+/// Check that the arguments are forwarded unconditionally even when the
+/// compiler is not in LTO mode.
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jmorse wrote:

Will "unused argument" warnings be produced, and should we check for them?

https://github.com/llvm/llvm-project/pull/158041