for musttail, also use tail call code to forward arguments

folkertdev · folkertdev · commit 2482d8f87147 · 2025-11-22T20:51:33.000+01:00
diff --git a/llvm/lib/Target/X86/X86ISelLoweringCall.cpp b/llvm/lib/Target/X86/X86ISelLoweringCall.cpp
@@ -2285,7 +2285,7 @@ X86TargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
         if (ShadowReg)
           RegsToPass.push_back(std::make_pair(ShadowReg, Arg));
       }
-    } else if (!IsSibcall && (!isTailCall || isByVal)) {
+    } else if (!IsSibcall && (!isTailCall || (isByVal && !IsMustTail))) {
       assert(VA.isMemLoc());
       if (!StackPtr.getNode())
         StackPtr = DAG.getCopyFromReg(Chain, dl, RegInfo->getStackRegister(),

Original file line number	Diff line number	Diff line change
`@@ -2285,7 +2285,7 @@ X86TargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,`
`2285`	`2285`	`if (ShadowReg)`
`2286`	`2286`	`RegsToPass.push_back(std::make_pair(ShadowReg, Arg));`
`2287`	`2287`	`}`
`2288`		`- } else if (!IsSibcall && (!isTailCall \|\| isByVal)) {`
	`2288`	`+ } else if (!IsSibcall && (!isTailCall \|\| (isByVal && !IsMustTail))) {`
`2289`	`2289`	`assert(VA.isMemLoc());`
`2290`	`2290`	`if (!StackPtr.getNode())`
`2291`	`2291`	`StackPtr = DAG.getCopyFromReg(Chain, dl, RegInfo->getStackRegister(),`