[llvm] [X86][APX] Support peephole optimization with CCMP instruction (PR #129994)

[Shengchen Kan via llvm-commits]

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@@ -0,0 +1,396 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
+# RUN: llc -o - %s -mtriple=x86_64-- -run-pass peephole-opt | FileCheck %s
+
+---
+name: opt_redundant_flags_adjusted_imm_0
+body: |
+  bb.0:
+    ; CHECK-LABEL: name: opt_redundant_flags_adjusted_imm_0
+    ; CHECK: [[COPY:%[0-9]+]]:gr64 = COPY $rsi
+    ; CHECK-NEXT: CCMP64ri32 [[COPY]], 1, 2, 5, implicit-def $eflags, implicit $eflags
+    ; CHECK-NEXT: $cl = SETCCr 4, implicit $eflags
+    ; CHECK-NEXT: $bl = SETCCr 15, implicit $eflags
+    ; CHECK-NEXT: $bl = SETCCr 7, implicit $eflags
+    ; CHECK-NEXT: $bl = SETCCr 14, implicit $eflags
+    ; CHECK-NEXT: $bl = SETCCr 6, implicit $eflags
+    %0:gr64 = COPY $rsi
+    ; CCMP+SETCC   %0 == 1
+    CCMP64ri32 %0, 1, 2, 5, implicit-def $eflags, implicit $eflags
+    $cl = SETCCr 4, implicit $eflags
+    ; CCMP+SETCC   %0 >= 2; CCMP can be removed.
+    CCMP64ri32 %0, 2, 2, 5, implicit-def $eflags, implicit $eflags
+    ; %0 >=s 2  -->  %0 >s 1
+    $bl = SETCCr 13, implicit $eflags
+    ; %0 >=u 2  -->  %0 >u 1
+    $bl = SETCCr 3, implicit $eflags
+    ; %0 <s 2  -->  %0 <=s 1
+    $bl = SETCCr 12, implicit $eflags
+    ; %0 <u 2  -->  %0 <=u 1
+    $bl = SETCCr 2, implicit $eflags
+...
+---
+name: opt_redundant_flags_adjusted_imm_1
+body: |
+  bb.0:
+    ; CHECK-LABEL: name: opt_redundant_flags_adjusted_imm_1
+    ; CHECK: [[COPY:%[0-9]+]]:gr64 = COPY $rsi
+    ; CHECK-NEXT: CCMP64ri32 [[COPY]], 42, 2, 5, implicit-def $eflags, implicit $eflags
+    ; CHECK-NEXT: $cl = SETCCr 5, implicit $eflags
+    ; CHECK-NEXT: $bl = SETCCr 13, implicit $eflags
+    ; CHECK-NEXT: $bl = SETCCr 3, implicit $eflags
+    ; CHECK-NEXT: $bl = SETCCr 12, implicit $eflags
+    ; CHECK-NEXT: $bl = SETCCr 2, implicit $eflags
+    %0:gr64 = COPY $rsi
+    ; CCMP+SETCC   %0 != 42
+    CCMP64ri32 %0, 42, 2, 5, implicit-def $eflags, implicit $eflags
+    $cl = SETCCr 5, implicit $eflags
+    ; CCMP+SETCC   %0 >= 2; CCMP can be removed.
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KanRobert wrote:

Comment here is incorrect?

https://github.com/llvm/llvm-project/pull/129994