JIT: Expand delegate calls in morph

[jakobbotsch]

Expand delegate calls in morph to allow CSE'ing and hoisting of delegate targets/instances.

Fix #75832 Close #75255

Also fix printing of GT_CALL nodes. Late args were not being printed in correct evaluation order.

[ghost]

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Issue Details

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Expand delegate calls in morph to allow CSE'ing and hoisting of delegate targets/instances.

Fix #75832 Close #75255

Author:	jakobbotsch
Assignees:	-
Labels:	area-CodeGen-coreclr
Milestone:	-

[jakobbotsch]

Looks like we may need to do something about #75751 before this to avoid regressions, I'm seeing many diffs like the following, where we now clobber an argument register containing a local we need:

 G_M13290_IG02:        ; gcrefRegs=00000002 {rcx}, byrefRegs=00000000 {}, byref
        ; gcrRegs +[rcx]
-       movzx    rdx, byte  ptr [rcx+10H]
+       mov      gword ptr [rsp+08H], rcx
+       ; GC ptr vars +{V00}
        mov      rax, gword ptr [rcx+08H]
        ; gcrRegs +[rax]
        mov      rcx, gword ptr [rax+08H]
-                                               ;; size=12 bbWeight=1    PerfScore 6.00
+       mov      rdx, gword ptr [rsp+08H]
+       ; gcrRegs +[rdx]
+       movzx    rdx, byte  ptr [rdx+10H]
+       ; gcrRegs -[rdx]
+                                               ;; size=22 bbWeight=1    PerfScore 8.00
 G_M13290_IG03:        ; , epilog, nogc, extend
-       tail.jmp [rax+18H]hackishMethodName
+       tail.jmp [rax+18H]

[ghost]

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