[llvm] [llvm] Allow Fast and Tail CC in UEFI (PR #138361)

[Prabhu Rajasekaran via llvm-commits]

https://github.com/Prabhuk created https://github.com/llvm/llvm-project/pull/138361

Allow tail call and fastcc optimizations for UEFI X86_64 targets.


>From f8e35c774c1cc8cd7cca2e3e66089c66bc195fbf Mon Sep 17 00:00:00 2001
From: prabhukr <prabhukr at google.com>
Date: Fri, 2 May 2025 23:20:21 +0000
Subject: [PATCH] [llvm] Allow Fast and Tail CC in UEFI

Allow tail call and fastcc optimizations for UEFI X86_64 targets.
---
 llvm/lib/Target/X86/X86Subtarget.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/llvm/lib/Target/X86/X86Subtarget.h b/llvm/lib/Target/X86/X86Subtarget.h
index a0b182d3f4c9b..c2b7d3780a983 100644
--- a/llvm/lib/Target/X86/X86Subtarget.h
+++ b/llvm/lib/Target/X86/X86Subtarget.h
@@ -352,9 +352,9 @@ class X86Subtarget final : public X86GenSubtargetInfo {
     switch (CC) {
     // On Win64, all these conventions just use the default convention.
     case CallingConv::C:
-      return isTargetWin64() || isTargetUEFI64();
     case CallingConv::Fast:
     case CallingConv::Tail:
+      return isTargetWin64() || isTargetUEFI64();
     case CallingConv::Swift:
     case CallingConv::SwiftTail:
     case CallingConv::X86_FastCall: