[llvm] [llvm] Support multiple save/restore points in mir (PR #119357)

[Michael Maitland via llvm-commits]

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@@ -0,0 +1,81 @@
+# RUN: llc -mtriple=x86_64 -run-pass none -o - %s | FileCheck %s
+# This test ensures that the MIR parser parses the save and restore points in
+# the machine frame info correctly.
+
+--- |
+
+  define i32 @foo(i32 %a, i32 %b) {
+  entry:
+    %tmp = alloca i32, align 4
+    %tmp2 = icmp slt i32 %a, %b
+    br i1 %tmp2, label %true, label %false
+
+  true:
+    store i32 %a, ptr %tmp, align 4
+    %tmp4 = call i32 @doSomething(i32 0, ptr %tmp)
+    br label %false
+
+  false:
+    %tmp.0 = phi i32 [ %tmp4, %true ], [ %a, %entry ]
+    ret i32 %tmp.0
+  }
+
+  declare i32 @doSomething(i32, ptr)
+
+...
+---
+name:            foo
+tracksRegLiveness: true
+liveins:
+  - { reg: '$edi' }
+  - { reg: '$esi' }
+# CHECK: frameInfo:
+# CHECK:      savePoint:
+# CHECK-NEXT:   - point:           '%bb.1'
+# CHECK-NEXT:   - point:           '%bb.2'
+# CHECK:      restorePoint:
+# CHECK-NEXT:   - point:           '%bb.2'
+# CHECK-NEXT:   - point:           '%bb.3'
+# CHECK: stack
+frameInfo:
+  maxAlignment:  4
+  hasCalls:      true
+  savePoint:
+    - point:     '%bb.1'
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michaelmaitland wrote:

Does this test need updating? What do the points correspond to? registers? frame idxs?

https://github.com/llvm/llvm-project/pull/119357