GlobalISel: Enable CSE of G_SELECT

Stop trying to delete a select in one combine since it would
be deleting the CSE'd instruction if that happened.

diff --git a/llvm/lib/CodeGen/GlobalISel/CSEInfo.cpp b/llvm/lib/CodeGen/GlobalISel/CSEInfo.cpp
index 6a0d1c3..4257fc6 100644 (file)
--- a/llvm/lib/CodeGen/GlobalISel/CSEInfo.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/CSEInfo.cpp
@@ -61,6 +61,7 @@ bool CSEConfigFull::shouldCSEOpc(unsigned Opc) {
   case TargetOpcode::G_TRUNC:
   case TargetOpcode::G_PTR_ADD:
   case TargetOpcode::G_EXTRACT:
+  case TargetOpcode::G_SELECT:
     return true;
   }
   return false;

diff --git a/llvm/lib/CodeGen/GlobalISel/CombinerHelper.cpp b/llvm/lib/CodeGen/GlobalISel/CombinerHelper.cpp
index 5ff3dd2..d9ae99f 100644 (file)
--- a/llvm/lib/CodeGen/GlobalISel/CombinerHelper.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/CombinerHelper.cpp
@@ -3262,8 +3262,6 @@ bool CombinerHelper::applyFoldBinOpIntoSelect(MachineInstr &MI,
   }
 
   Builder.buildSelect(Dst, SelectCond, FoldTrue, FoldFalse, MI.getFlags());
-  Observer.erasingInstr(*Select);
-  Select->eraseFromParent();
   MI.eraseFromParent();
 
   return true;

diff --git a/llvm/test/CodeGen/AMDGPU/GlobalISel/combine-fold-binop-into-select.mir b/llvm/test/CodeGen/AMDGPU/GlobalISel/combine-fold-binop-into-select.mir
index add7816..b633fff 100644 (file)
--- a/llvm/test/CodeGen/AMDGPU/GlobalISel/combine-fold-binop-into-select.mir
+++ b/llvm/test/CodeGen/AMDGPU/GlobalISel/combine-fold-binop-into-select.mir
@@ -938,8 +938,8 @@ body: |
     ; CHECK-NEXT: %cond:_(s1) = G_ICMP intpred(eq), %reg(s32), %zero
     ; CHECK-NEXT: %ten:_(s32) = G_CONSTANT i32 10
     ; CHECK-NEXT: %twenty:_(s32) = G_CONSTANT i32 20
-    ; CHECK-NEXT: %smin:_(s32) = G_SELECT %cond(s1), %ten, %twenty
-    ; CHECK-NEXT: S_ENDPGM 0, implicit %smin(s32)
+    ; CHECK-NEXT: %select:_(s32) = G_SELECT %cond(s1), %ten, %twenty
+    ; CHECK-NEXT: S_ENDPGM 0, implicit %select(s32)
     %reg:_(s32) = COPY $vgpr0
     %zero:_(s32) = G_CONSTANT i32 0
     %cond:_(s1) = G_ICMP intpred(eq), %reg, %zero
@@ -987,8 +987,8 @@ body: |
     ; CHECK-NEXT: %cond:_(s1) = G_ICMP intpred(eq), %reg(s32), %zero
     ; CHECK-NEXT: %ten:_(s32) = G_CONSTANT i32 10
     ; CHECK-NEXT: %twenty:_(s32) = G_CONSTANT i32 20
-    ; CHECK-NEXT: %umin:_(s32) = G_SELECT %cond(s1), %ten, %twenty
-    ; CHECK-NEXT: S_ENDPGM 0, implicit %umin(s32)
+    ; CHECK-NEXT: %select:_(s32) = G_SELECT %cond(s1), %ten, %twenty
+    ; CHECK-NEXT: S_ENDPGM 0, implicit %select(s32)
     %reg:_(s32) = COPY $vgpr0
     %zero:_(s32) = G_CONSTANT i32 0
     %cond:_(s1) = G_ICMP intpred(eq), %reg, %zero