[llvm] [GlobalIsel] combine ext of trunc with flags (PR #87115)

[Thorsten Schütt via llvm-commits]

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@@ -0,0 +1,156 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
+# RUN: llc -run-pass=aarch64-prelegalizer-combiner -verify-machineinstrs -mtriple aarch64-unknown-unknown %s -o - | FileCheck %s
+
+---
+name:            zext_trunc_nuw
+body:             |
+  bb.0:
+    liveins: $w0, $w1
+    ; CHECK-LABEL: name: zext_trunc_nuw
+    ; CHECK: liveins: $w0, $w1
+    ; CHECK-NEXT: {{  $}}
+    ; CHECK-NEXT: [[COPY:%[0-9]+]]:_(s64) = COPY $x0
+    ; CHECK-NEXT: $x1 = COPY [[COPY]](s64)
+    %0:_(s64) = COPY $x0
+    %2:_(s32) = nuw G_TRUNC %0
+    %3:_(s64) = G_ZEXT  %2
+    $x1 = COPY %3
+...
+---
+name:            zext_trunc_nsw
+body:             |
+  bb.0:
+    liveins: $w0, $w1
+    ; CHECK-LABEL: name: zext_trunc_nsw
+    ; CHECK: liveins: $w0, $w1
+    ; CHECK-NEXT: {{  $}}
+    ; CHECK-NEXT: [[COPY:%[0-9]+]]:_(s64) = COPY $x0
+    ; CHECK-NEXT: [[TRUNC:%[0-9]+]]:_(s32) = nsw G_TRUNC [[COPY]](s64)
+    ; CHECK-NEXT: [[ZEXT:%[0-9]+]]:_(s64) = G_ZEXT [[TRUNC]](s32)
+    ; CHECK-NEXT: $x1 = COPY [[ZEXT]](s64)
+    %0:_(s64) = COPY $x0
+    %2:_(s32) = nsw G_TRUNC %0
+    %3:_(s64) = G_ZEXT  %2
+    $x1 = COPY %3
+...
+---
+name:            zext_trunc
+body:             |
+  bb.0:
+    liveins: $w0, $w1
+    ; CHECK-LABEL: name: zext_trunc
+    ; CHECK: liveins: $w0, $w1
+    ; CHECK-NEXT: {{  $}}
+    ; CHECK-NEXT: [[COPY:%[0-9]+]]:_(s64) = COPY $x0
+    ; CHECK-NEXT: [[TRUNC:%[0-9]+]]:_(s32) = G_TRUNC [[COPY]](s64)
+    ; CHECK-NEXT: [[ZEXT:%[0-9]+]]:_(s64) = G_ZEXT [[TRUNC]](s32)
+    ; CHECK-NEXT: $x1 = COPY [[ZEXT]](s64)
+    %0:_(s64) = COPY $x0
+    %2:_(s32) = G_TRUNC %0
+    %3:_(s64) = G_ZEXT  %2
+    $x1 = COPY %3
+...
+---
+name:            zext_trunc_nuw_vector
+body:             |
+  bb.0:
+    liveins: $w0, $w1
+    ; CHECK-LABEL: name: zext_trunc_nuw_vector
+    ; CHECK: liveins: $w0, $w1
+    ; CHECK-NEXT: {{  $}}
+    ; CHECK-NEXT: [[COPY:%[0-9]+]]:_(s32) = COPY $w0
+    ; CHECK-NEXT: [[COPY1:%[0-9]+]]:_(s32) = COPY $w1
+    ; CHECK-NEXT: %bv0:_(<4 x s32>) = G_BUILD_VECTOR [[COPY]](s32), [[COPY1]](s32), [[COPY]](s32), [[COPY1]](s32)
+    ; CHECK-NEXT: $q0 = COPY %bv0(<4 x s32>)
+    ; CHECK-NEXT: RET_ReallyLR implicit $w0
+    %0:_(s32) = COPY $w0
+    %1:_(s32) = COPY $w1
+    %2:_(s32) = COPY $w2
+    %3:_(s32) = COPY $w3
+    %bv0:_(<4 x s32>) = G_BUILD_VECTOR %0:_(s32), %1:_(s32), %0:_(s32), %1:_(s32)
+    %trunc:_(<4 x s16>) = nuw G_TRUNC %bv0
+    %zext:_(<4 x s32>) = G_ZEXT  %trunc
+    $q0 = COPY %zext(<4 x s32>)
+    RET_ReallyLR implicit $w0
+...
+---
+name:            sext_trunc_nsw
+body:             |
+  bb.0:
+    liveins: $w0, $w1
+    ; CHECK-LABEL: name: sext_trunc_nsw
+    ; CHECK: liveins: $w0, $w1
+    ; CHECK-NEXT: {{  $}}
+    ; CHECK-NEXT: [[COPY:%[0-9]+]]:_(s64) = COPY $x0
+    ; CHECK-NEXT: $x1 = COPY [[COPY]](s64)
+    %0:_(s64) = COPY $x0
+    %2:_(s32) = nsw G_TRUNC %0
+    %3:_(s64) = G_SEXT  %2
+    $x1 = COPY %3
+...
+---
+name:            sext_trunc_nuw
+body:             |
+  bb.0:
+    liveins: $w0, $w1
+    ; CHECK-LABEL: name: sext_trunc_nuw
+    ; CHECK: liveins: $w0, $w1
+    ; CHECK-NEXT: {{  $}}
+    ; CHECK-NEXT: [[COPY:%[0-9]+]]:_(s64) = COPY $x0
+    ; CHECK-NEXT: [[TRUNC:%[0-9]+]]:_(s32) = nuw G_TRUNC [[COPY]](s64)
+    ; CHECK-NEXT: [[SEXT:%[0-9]+]]:_(s64) = G_SEXT [[TRUNC]](s32)
+    ; CHECK-NEXT: $x1 = COPY [[SEXT]](s64)
+    %0:_(s64) = COPY $x0
+    %2:_(s32) = nuw G_TRUNC %0
+    %3:_(s64) = G_SEXT  %2
+    $x1 = COPY %3
+...
+---
+name:            sext_trunc
+body:             |
+  bb.0:
+    liveins: $w0, $w1
+    ; CHECK-LABEL: name: sext_trunc
+    ; CHECK: liveins: $w0, $w1
+    ; CHECK-NEXT: {{  $}}
+    ; CHECK-NEXT: [[COPY:%[0-9]+]]:_(s64) = COPY $x0
+    ; CHECK-NEXT: [[TRUNC:%[0-9]+]]:_(s32) = G_TRUNC [[COPY]](s64)
+    ; CHECK-NEXT: [[SEXT:%[0-9]+]]:_(s64) = G_SEXT [[TRUNC]](s32)
+    ; CHECK-NEXT: $x1 = COPY [[SEXT]](s64)
+    %0:_(s64) = COPY $x0
+    %2:_(s32) = G_TRUNC %0
+    %3:_(s64) = G_SEXT  %2
+    $x1 = COPY %3
+...
+---
+name:            sext_trunc_nsw_types_wrong
+body:             |
+  bb.0:
+    liveins: $w0, $w1
+    ; CHECK-LABEL: name: sext_trunc_nsw_types_wrong
+    ; CHECK: liveins: $w0, $w1
+    ; CHECK-NEXT: {{  $}}
+    ; CHECK-NEXT: [[COPY:%[0-9]+]]:_(s64) = COPY $x0
+    ; CHECK-NEXT: [[TRUNC:%[0-9]+]]:_(s16) = nsw G_TRUNC [[COPY]](s64)
+    ; CHECK-NEXT: [[SEXT:%[0-9]+]]:_(s32) = G_SEXT [[TRUNC]](s16)
+    ; CHECK-NEXT: $w1 = COPY [[SEXT]](s32)
+    %0:_(s64) = COPY $x0
+    %2:_(s16) = nsw G_TRUNC %0
----------------
tschuett wrote:

This test failed because the types s64 and s32 don't match. The correct flag nsw was set. 

https://github.com/llvm/llvm-project/pull/87115