[llvm-branch-commits] [llvm] [TargetInstrInfo] Fix folding inline asm operands next to tied operands (PR #229627)

[Bill Wendling via llvm-branch-commits]

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@@ -0,0 +1,80 @@
+# RUN: llc -mtriple=x86_64-unknown-linux-gnu -run-pass=greedy \
+# RUN:   -verify-machineinstrs %s -o - | FileCheck %s
+
+# The greedy register allocator spills a value used by a foldable ("rm")
+# inline asm operand by folding the operand to the value's stack slot. The
+# clobbers below leave six GPRs, and the asm needs seven registers, so one
+# value is spilled. Folding replaces an operand with the five operands of a
+# memory reference, moving every operand after it, which must keep any tied
+# operands tied.
+
+---
+# One value passed to two "rm" operands: both operands fold to its stack slot.
+name: rm_same_value_twice
+tracksRegLiveness: true
+fixedStack:
+  - { id: 0, size: 8, alignment: 16, isImmutable: true }
+body: |
+  bb.0:
+    liveins: $rdi, $rsi, $rdx, $rcx, $r8, $r9
+
+    ; CHECK-LABEL: name: rm_same_value_twice
+    ; CHECK: INLINEASM &"", sideeffect mayload attdialect, mem:m, %stack.[[SLOT:[0-9]+]], 1, $noreg, 0, $noreg, mem:m, %stack.[[SLOT]], 1, $noreg, 0, $noreg, reguse:GR64,
+    %0:gr64 = COPY $rdi
+    %1:gr64 = COPY $rsi
+    %2:gr64 = COPY $rdx
+    %3:gr64 = COPY $rcx
+    %4:gr64 = COPY $r8
+    %5:gr64 = COPY $r9
+    %6:gr64 = MOV64rm %fixed-stack.0, 1, $noreg, 0, $noreg :: (load (s64) from %fixed-stack.0, align 16)
+    INLINEASM &"", sideeffect attdialect, reguse:GR64 foldable, %0, reguse:GR64 foldable, %0, reguse:GR64, %1, reguse:GR64, %2, reguse:GR64, %3, reguse:GR64, %4, reguse:GR64, %5, reguse:GR64, %6, clobber, implicit-def dead early-clobber $rax, clobber, implicit-def dead early-clobber $rbx, clobber, implicit-def dead early-clobber $rbp, clobber, implicit-def dead early-clobber $r10, clobber, implicit-def dead early-clobber $r11, clobber, implicit-def dead early-clobber $r12, clobber, implicit-def dead early-clobber $r13, clobber, implicit-def dead early-clobber $r14, clobber, implicit-def dead early-clobber $r15
+    RET 0
+...
+---
+# Folding the "rm" input moves the input tied to the "=r" output after it.
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isanbard wrote:

Done.

https://github.com/llvm/llvm-project/pull/229627