[lld] [lld] [MinGW] Support targeting ARM64EC (PR #78911)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-lld-elf

Author: Billy Laws (bylaws)

<details>
<summary>Changes</summary>

'arm64ecpe' was chosen arbitrarily as gcc MinGW doesn't provide EC support.

CC: @<!-- -->cjacek 

---
Full diff: https://github.com/llvm/llvm-project/pull/78911.diff


3 Files Affected:

- (modified) lld/Common/DriverDispatcher.cpp (+2-1) 
- (modified) lld/MinGW/Driver.cpp (+3) 
- (modified) lld/test/MinGW/driver.test (+6) 


``````````diff
diff --git a/lld/Common/DriverDispatcher.cpp b/lld/Common/DriverDispatcher.cpp
index 435acfd277654b..f5c8bcdef4e0f0 100644
--- a/lld/Common/DriverDispatcher.cpp
+++ b/lld/Common/DriverDispatcher.cpp
@@ -44,7 +44,8 @@ static cl::TokenizerCallback getDefaultQuotingStyle() {
 }
 
 static bool isPETargetName(StringRef s) {
-  return s == "i386pe" || s == "i386pep" || s == "thumb2pe" || s == "arm64pe";
+  return s == "i386pe" || s == "i386pep" || s == "thumb2pe" || s == "arm64pe" ||
+         s == "arm64ecpe";
 }
 
 static std::optional<bool> isPETarget(llvm::ArrayRef<const char *> args) {
diff --git a/lld/MinGW/Driver.cpp b/lld/MinGW/Driver.cpp
index 4752d92e3b1d71..290eecaacda7d4 100644
--- a/lld/MinGW/Driver.cpp
+++ b/lld/MinGW/Driver.cpp
@@ -346,6 +346,7 @@ bool link(ArrayRef<const char *> argsArr, llvm::raw_ostream &stdoutOS,
 
   if (args.getLastArgValue(OPT_m) != "thumb2pe" &&
       args.getLastArgValue(OPT_m) != "arm64pe" &&
+      args.getLastArgValue(OPT_m) != "arm64ecpe" &&
       args.hasFlag(OPT_disable_dynamicbase, OPT_dynamicbase, false))
     add("-dynamicbase:no");
   if (args.hasFlag(OPT_disable_high_entropy_va, OPT_high_entropy_va, false))
@@ -409,6 +410,8 @@ bool link(ArrayRef<const char *> argsArr, llvm::raw_ostream &stdoutOS,
       add("-machine:arm");
     else if (s == "arm64pe")
       add("-machine:arm64");
+    else if (s == "arm64ecpe")
+      add("-machine:arm64ec");
     else
       error("unknown parameter: -m" + s);
   }
diff --git a/lld/test/MinGW/driver.test b/lld/test/MinGW/driver.test
index 559a32bfa242f8..46b3b6d7a862a6 100644
--- a/lld/test/MinGW/driver.test
+++ b/lld/test/MinGW/driver.test
@@ -25,6 +25,12 @@ ARM64-SAME: -machine:arm64
 ARM64-SAME: -alternatename:__image_base__=__ImageBase
 ARM64-SAME: foo.o
 
+RUN: ld.lld -### foo.o -m arm64ecpe 2>&1 | FileCheck -check-prefix=ARM64EC %s
+ARM64EC:      -out:a.exe
+ARM64EC-SAME: -machine:arm64ec
+ARM64EC-SAME: -alternatename:__image_base__=__ImageBase
+ARM64EC-SAME: foo.o
+
 RUN: ld.lld -### foo.o -m i386pep -shared 2>&1 | FileCheck -check-prefix=SHARED %s
 RUN: ld.lld -### foo.o -m i386pep --shared 2>&1 | FileCheck -check-prefix=SHARED %s
 RUN: ld.lld -### foo.o -m i386pep --dll 2>&1 | FileCheck -check-prefix=SHARED %s

``````````

</details>


https://github.com/llvm/llvm-project/pull/78911