Merge pull request #19914 from CarolEidt/AltJitTailCall

CarolEidt · web-flow · commit 9ff41e739123 · 2018-10-15T17:27:22.000Z
Dummy TailCallCopyArgsThunk for altjit
diff --git a/src/jit/morph.cpp b/src/jit/morph.cpp
@@ -8312,7 +8312,15 @@ GenTree* Compiler::fgMorphCall(GenTreeCall* call)
                                                                               : CORINFO_TAILCALL_NORMAL);
             if (pfnCopyArgs == nullptr)
             {
-                szFailReason = "TailCallCopyArgsThunk not available.";
+                if (!info.compMatchedVM)
+                {
+                    // If we don't have a matched VM, we won't get valid results when asking for a thunk.
+                    pfnCopyArgs = (void*)0xCA11CA11; // "callcall"
+                }
+                else
+                {
+                    szFailReason = "TailCallCopyArgsThunk not available.";
+                }
             }
         }
 #endif // !_TARGET_X86_

Original file line number	Diff line number	Diff line change
`@@ -8312,7 +8312,15 @@ GenTree* Compiler::fgMorphCall(GenTreeCall* call)`
`8312`	`8312`	`: CORINFO_TAILCALL_NORMAL);`
`8313`	`8313`	`if (pfnCopyArgs == nullptr)`
`8314`	`8314`	`{`
`8315`		`- szFailReason = "TailCallCopyArgsThunk not available.";`
	`8315`	`+ if (!info.compMatchedVM)`
	`8316`	`+ {`
	`8317`	`+ // If we don't have a matched VM, we won't get valid results when asking for a thunk.`
	`8318`	`+ pfnCopyArgs = (void*)0xCA11CA11; // "callcall"`
	`8319`	`+ }`
	`8320`	`+ else`
	`8321`	`+ {`
	`8322`	`+ szFailReason = "TailCallCopyArgsThunk not available.";`
	`8323`	`+ }`
`8316`	`8324`	`}`
`8317`	`8325`	`}`
`8318`	`8326`	`#endif // !_TARGET_X86_`