[llvm] [Xtensa] Implement Windowed Register Option. (PR #124656)

[Andrei Safronov via llvm-commits]

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@@ -0,0 +1,105 @@
+# RUN: llvm-mc %s -triple=xtensa -show-encoding --mattr=+windowed \
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andreisfr wrote:

@MaskRay, thank you very much for comments. I used update_mc_test_checks.py to update tests. All tests updated except "llvm/test/MC/Xtensa/windowed.s". It seems script produces incorrect result. 

For asm code:
	call4	LBL0                            # encoding: [0bAA010101,A,A]
                                        #   fixup A - offset: 0, value: LBL0, kind: fixup_xtensa_call_18
this utility generates:
// CHECK: call4	LBL0                            # encoding: [0bAA010101,A,A]#   fixup A - offset: 0, value: LBL0, kind: fixup_xtensa_call_18

instead of for example:
// CHECK: call4	LBL0                            # encoding: [0bAA010101,A,A]
// CHECK-NEXT: #   fixup A - offset: 0, value: LBL0, kind: fixup_xtensa_call_18

So, maybe we should investigate and prepare fix for this problem?

https://github.com/llvm/llvm-project/pull/124656