[llvm] Xtensa] Implement windowed call ABI. (PR #130001)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,103 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=xtensa -O1 -mattr=+windowed -verify-machineinstrs < %s \
+; RUN:   | FileCheck %s -check-prefix=XTENSA
+
+; Check placement of first 6 arguments in registers and 7th argument on stack
+define dso_local i32 @test1(i32 noundef %0, i32 noundef %1, i32 noundef %2, i32 noundef %3, i32 noundef %4, i32 noundef %5, ptr nocapture noundef readonly byval(i32) align 4 %6) {
+; XTENSA-LABEL: test1:
+; XTENSA:         .cfi_startproc
+; XTENSA-NEXT:  # %bb.0:
+; XTENSA-NEXT:    entry a1, 32
+; XTENSA-NEXT:    .cfi_def_cfa_offset 32
+; XTENSA-NEXT:    add a8, a7, a2
+; XTENSA-NEXT:    l32i a9, a1, 32
+; XTENSA-NEXT:    add a2, a8, a9
+; XTENSA-NEXT:    retw
+  %8 = load i32, ptr %6, align 4
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arsenm wrote:

Use named values in tests 

https://github.com/llvm/llvm-project/pull/130001