[llvm] [KeyInstr][DwarfDebug] Add is_stmt emission support (PR #133495)

[Orlando Cazalet-Hyams via llvm-commits]

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@@ -0,0 +1,117 @@
+; RUN: llc %s --filetype=obj -o - --dwarf-use-key-instructions \
+; RUN: | llvm-objdump -d - --no-show-raw-insn \
+; RUN: | FileCheck %s --check-prefix=OBJ
+
+; RUN: llc %s --filetype=obj -o - --dwarf-use-key-instructions \
+; RUN: | llvm-dwarfdump - --debug-line \
+; RUN: | FileCheck %s --check-prefix=DBG
+
+; OBJ:0000000000000000 <fun>:
+; OBJ-NEXT:  0:       pushq   %rbp
+; OBJ-NEXT:  1:       pushq   %r14
+; OBJ-NEXT:  3:       pushq   %rbx
+; OBJ-NEXT:  4:       movq    (%rip), %rax
+; OBJ-NEXT:  b:       movl    (%rax), %ebp
+; OBJ-NEXT:  d:       callq   0x12 <fun+0x12>
+; OBJ-NEXT: 12:       callq   0x17 <fun+0x17>
+; OBJ-NEXT: 17:       movl    %eax, %ebx
+; OBJ-NEXT: 19:       addl    %ebp, %ebx
+; OBJ-NEXT: 1b:       movq    (%rip), %r14
+; OBJ-NEXT: 22:       movl    $0x1, (%r14)
+; OBJ-NEXT: 29:       callq   0x2e <fun+0x2e>
+; OBJ-NEXT: 2e:       movl    $0x2, (%r14)
+; OBJ-NEXT: 35:       callq   0x3a <fun+0x3a>
+; OBJ-NEXT: 3a:       movl    $0x3, (%r14)
+; OBJ-NEXT: 41:       callq   0x46 <fun+0x46>
+; OBJ-NEXT: 46:       movl    $0x4, (%r14)
+; OBJ-NEXT: 4d:       callq   0x52 <fun+0x52>
+; OBJ-NEXT: 52:       movl    %ebx, %eax
+; OBJ-NEXT: 54:       popq    %rbx
+; OBJ-NEXT: 55:       popq    %r14
+; OBJ-NEXT: 57:       popq    %rbp
+; OBJ-NEXT: 58:       retq
+
+; DBG:      Address            Line   Column File   ISA Discriminator OpIndex Flags
+; DBG-NEXT: ------------------ ------ ------ ------ --- ------------- ------- -------------
+; DBG-NEXT: 0x0000000000000000      1      0      0   0             0       0  is_stmt
+; DBG-NEXT: 0x0000000000000004      2      0      0   0             0       0  is_stmt prologue_end
+
+;; Test A:
+;; Check the 1st call (line 3) gets is_stmt despite having no atom group.
+; DBG-NEXT: 0x000000000000000d      3      0      0   0             0       0  is_stmt
+
+;; Test B:
+;; Check the 2nd call (line 4) gets is_stmt applied despite being part of group
+;; 1 and having lower precedence than the add. Check that the add stil gets
+;; is_stmt applied.
+;; There are two is_stmt line 4 entries are is_stmt because we don't float
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OCHyams wrote:

done

https://github.com/llvm/llvm-project/pull/133495