[llvm] r305509 - [InstCombine] Add test cases to demonstrate instcombine increasing instruction count when trying to fold (select (icmp eq (and X, C1), 0), Y, (or Y, C2))->(or (shl (and X, C1), C3), y) when the pieces have multiple uses.
Craig Topper via llvm-commits
llvm-commits at lists.llvm.org
Thu Jun 15 14:38:45 PDT 2017
Author: ctopper
Date: Thu Jun 15 16:38:44 2017
New Revision: 305509
URL: http://llvm.org/viewvc/llvm-project?rev=305509&view=rev
Log:
[InstCombine] Add test cases to demonstrate instcombine increasing instruction count when trying to fold (select (icmp eq (and X, C1), 0), Y, (or Y, C2))->(or (shl (and X, C1), C3), y) when the pieces have multiple uses.
Modified:
llvm/trunk/test/Transforms/InstCombine/select-with-bitwise-ops.ll
Modified: llvm/trunk/test/Transforms/InstCombine/select-with-bitwise-ops.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/select-with-bitwise-ops.ll?rev=305509&r1=305508&r2=305509&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/select-with-bitwise-ops.ll (original)
+++ llvm/trunk/test/Transforms/InstCombine/select-with-bitwise-ops.ll Thu Jun 15 16:38:44 2017
@@ -326,3 +326,240 @@ define i32 @test69(i32 %x, i32 %y) {
%select = select i1 %cmp, i32 %y, i32 %or
ret i32 %select
}
+
+define i32 @shift_no_xor_multiuse_or(i32 %x, i32 %y) {
+; CHECK-LABEL: @shift_no_xor_multiuse_or(
+; CHECK-NEXT: [[OR:%.*]] = or i32 [[Y:%.*]], 2
+; CHECK-NEXT: [[AND:%.*]] = shl i32 [[X:%.*]], 1
+; CHECK-NEXT: [[TMP1:%.*]] = and i32 [[AND]], 2
+; CHECK-NEXT: [[TMP2:%.*]] = or i32 [[TMP1]], [[Y]]
+; CHECK-NEXT: [[RES:%.*]] = mul i32 [[TMP2]], [[OR]]
+; CHECK-NEXT: ret i32 [[RES]]
+;
+ %and = and i32 %x, 1
+ %cmp = icmp eq i32 %and, 0
+ %or = or i32 %y, 2
+ %select = select i1 %cmp, i32 %y, i32 %or
+ %res = mul i32 %select, %or ; to bump up use count of the Or
+ ret i32 %res
+}
+
+define i32 @no_shift_no_xor_multiuse_or(i32 %x, i32 %y) {
+; CHECK-LABEL: @no_shift_no_xor_multiuse_or(
+; CHECK-NEXT: [[AND:%.*]] = and i32 [[X:%.*]], 4096
+; CHECK-NEXT: [[OR:%.*]] = or i32 [[Y:%.*]], 4096
+; CHECK-NEXT: [[TMP1:%.*]] = or i32 [[AND]], [[Y]]
+; CHECK-NEXT: [[RES:%.*]] = mul i32 [[TMP1]], [[OR]]
+; CHECK-NEXT: ret i32 [[RES]]
+;
+ %and = and i32 %x, 4096
+ %cmp = icmp eq i32 %and, 0
+ %or = or i32 %y, 4096
+ %select = select i1 %cmp, i32 %y, i32 %or
+ %res = mul i32 %select, %or ; to bump up use count of the Or
+ ret i32 %res
+}
+
+define i32 @no_shift_xor_multiuse_or(i32 %x, i32 %y) {
+; CHECK-LABEL: @no_shift_xor_multiuse_or(
+; CHECK-NEXT: [[AND:%.*]] = and i32 [[X:%.*]], 4096
+; CHECK-NEXT: [[OR:%.*]] = or i32 [[Y:%.*]], 4096
+; CHECK-NEXT: [[TMP1:%.*]] = xor i32 [[AND]], 4096
+; CHECK-NEXT: [[TMP2:%.*]] = or i32 [[TMP1]], [[Y]]
+; CHECK-NEXT: [[RES:%.*]] = mul i32 [[TMP2]], [[OR]]
+; CHECK-NEXT: ret i32 [[RES]]
+;
+ %and = and i32 %x, 4096
+ %cmp = icmp ne i32 0, %and
+ %or = or i32 %y, 4096
+ %select = select i1 %cmp, i32 %y, i32 %or
+ %res = mul i32 %select, %or ; to bump up use count of the Or
+ ret i32 %res
+}
+
+; TODO this increased the number of instructions
+define i32 @shift_xor_multiuse_or(i32 %x, i32 %y) {
+; CHECK-LABEL: @shift_xor_multiuse_or(
+; CHECK-NEXT: [[OR:%.*]] = or i32 [[Y:%.*]], 2048
+; CHECK-NEXT: [[AND:%.*]] = lshr i32 [[X:%.*]], 1
+; CHECK-NEXT: [[TMP1:%.*]] = and i32 [[AND]], 2048
+; CHECK-NEXT: [[TMP2:%.*]] = xor i32 [[TMP1]], 2048
+; CHECK-NEXT: [[TMP3:%.*]] = or i32 [[TMP2]], [[Y]]
+; CHECK-NEXT: [[RES:%.*]] = mul i32 [[TMP3]], [[OR]]
+; CHECK-NEXT: ret i32 [[RES]]
+;
+ %and = and i32 %x, 4096
+ %cmp = icmp ne i32 0, %and
+ %or = or i32 %y, 2048
+ %select = select i1 %cmp, i32 %y, i32 %or
+ %res = mul i32 %select, %or ; to bump up use count of the Or
+ ret i32 %res
+}
+
+define i32 @shift_no_xor_multiuse_cmp(i32 %x, i32 %y, i32 %z, i32 %w) {
+; CHECK-LABEL: @shift_no_xor_multiuse_cmp(
+; CHECK-NEXT: [[AND:%.*]] = and i32 [[X:%.*]], 1
+; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[AND]], 0
+; CHECK-NEXT: [[TMP1:%.*]] = shl nuw nsw i32 [[AND]], 1
+; CHECK-NEXT: [[TMP2:%.*]] = or i32 [[TMP1]], [[Y:%.*]]
+; CHECK-NEXT: [[SELECT2:%.*]] = select i1 [[CMP]], i32 [[Z:%.*]], i32 [[W:%.*]]
+; CHECK-NEXT: [[RES:%.*]] = mul i32 [[TMP2]], [[SELECT2]]
+; CHECK-NEXT: ret i32 [[RES]]
+;
+ %and = and i32 %x, 1
+ %cmp = icmp eq i32 %and, 0
+ %or = or i32 %y, 2
+ %select = select i1 %cmp, i32 %y, i32 %or
+ %select2 = select i1 %cmp, i32 %z, i32 %w ; to bump up use count of the cmp
+ %res = mul i32 %select, %select2
+ ret i32 %res
+}
+
+define i32 @no_shift_no_xor_multiuse_cmp(i32 %x, i32 %y, i32 %z, i32 %w) {
+; CHECK-LABEL: @no_shift_no_xor_multiuse_cmp(
+; CHECK-NEXT: [[AND:%.*]] = and i32 [[X:%.*]], 4096
+; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[AND]], 0
+; CHECK-NEXT: [[TMP1:%.*]] = or i32 [[AND]], [[Y:%.*]]
+; CHECK-NEXT: [[SELECT2:%.*]] = select i1 [[CMP]], i32 [[Z:%.*]], i32 [[W:%.*]]
+; CHECK-NEXT: [[RES:%.*]] = mul i32 [[TMP1]], [[SELECT2]]
+; CHECK-NEXT: ret i32 [[RES]]
+;
+ %and = and i32 %x, 4096
+ %cmp = icmp eq i32 %and, 0
+ %or = or i32 %y, 4096
+ %select = select i1 %cmp, i32 %y, i32 %or
+ %select2 = select i1 %cmp, i32 %z, i32 %w ; to bump up use count of the cmp
+ %res = mul i32 %select, %select2
+ ret i32 %res
+}
+
+define i32 @no_shift_xor_multiuse_cmp(i32 %x, i32 %y, i32 %z, i32 %w) {
+; CHECK-LABEL: @no_shift_xor_multiuse_cmp(
+; CHECK-NEXT: [[AND:%.*]] = and i32 [[X:%.*]], 4096
+; CHECK-NEXT: [[CMP:%.*]] = icmp ne i32 [[AND]], 0
+; CHECK-NEXT: [[TMP1:%.*]] = xor i32 [[AND]], 4096
+; CHECK-NEXT: [[TMP2:%.*]] = or i32 [[TMP1]], [[Y:%.*]]
+; CHECK-NEXT: [[SELECT2:%.*]] = select i1 [[CMP]], i32 [[Z:%.*]], i32 [[W:%.*]]
+; CHECK-NEXT: [[RES:%.*]] = mul i32 [[TMP2]], [[SELECT2]]
+; CHECK-NEXT: ret i32 [[RES]]
+;
+ %and = and i32 %x, 4096
+ %cmp = icmp ne i32 0, %and
+ %or = or i32 %y, 4096
+ %select = select i1 %cmp, i32 %y, i32 %or
+ %select2 = select i1 %cmp, i32 %z, i32 %w ; to bump up use count of the cmp
+ %res = mul i32 %select, %select2
+ ret i32 %res
+}
+
+; TODO this increased the number of instructions
+define i32 @shift_xor_multiuse_cmp(i32 %x, i32 %y, i32 %z, i32 %w) {
+; CHECK-LABEL: @shift_xor_multiuse_cmp(
+; CHECK-NEXT: [[AND:%.*]] = and i32 [[X:%.*]], 4096
+; CHECK-NEXT: [[CMP:%.*]] = icmp ne i32 [[AND]], 0
+; CHECK-NEXT: [[TMP1:%.*]] = lshr exact i32 [[AND]], 1
+; CHECK-NEXT: [[TMP2:%.*]] = xor i32 [[TMP1]], 2048
+; CHECK-NEXT: [[TMP3:%.*]] = or i32 [[TMP2]], [[Y:%.*]]
+; CHECK-NEXT: [[SELECT2:%.*]] = select i1 [[CMP]], i32 [[Z:%.*]], i32 [[W:%.*]]
+; CHECK-NEXT: [[RES:%.*]] = mul i32 [[TMP3]], [[SELECT2]]
+; CHECK-NEXT: ret i32 [[RES]]
+;
+ %and = and i32 %x, 4096
+ %cmp = icmp ne i32 0, %and
+ %or = or i32 %y, 2048
+ %select = select i1 %cmp, i32 %y, i32 %or
+ %select2 = select i1 %cmp, i32 %z, i32 %w ; to bump up use count of the cmp
+ %res = mul i32 %select, %select2
+ ret i32 %res
+}
+
+; TODO this increased the number of instructions
+define i32 @shift_no_xor_multiuse_cmp_or(i32 %x, i32 %y, i32 %z, i32 %w) {
+; CHECK-LABEL: @shift_no_xor_multiuse_cmp_or(
+; CHECK-NEXT: [[AND:%.*]] = and i32 [[X:%.*]], 1
+; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[AND]], 0
+; CHECK-NEXT: [[OR:%.*]] = or i32 [[Y:%.*]], 2
+; CHECK-NEXT: [[TMP1:%.*]] = shl nuw nsw i32 [[AND]], 1
+; CHECK-NEXT: [[TMP2:%.*]] = or i32 [[TMP1]], [[Y]]
+; CHECK-NEXT: [[SELECT2:%.*]] = select i1 [[CMP]], i32 [[Z:%.*]], i32 [[W:%.*]]
+; CHECK-NEXT: [[RES:%.*]] = mul i32 [[TMP2]], [[SELECT2]]
+; CHECK-NEXT: [[RES2:%.*]] = mul i32 [[RES]], [[OR]]
+; CHECK-NEXT: ret i32 [[RES2]]
+;
+ %and = and i32 %x, 1
+ %cmp = icmp eq i32 %and, 0
+ %or = or i32 %y, 2
+ %select = select i1 %cmp, i32 %y, i32 %or
+ %select2 = select i1 %cmp, i32 %z, i32 %w ; to bump up use count of the cmp
+ %res = mul i32 %select, %select2
+ %res2 = mul i32 %res, %or ; to bump up the use count of the or
+ ret i32 %res2
+}
+
+define i32 @no_shift_no_xor_multiuse_cmp_or(i32 %x, i32 %y, i32 %z, i32 %w) {
+; CHECK-LABEL: @no_shift_no_xor_multiuse_cmp_or(
+; CHECK-NEXT: [[AND:%.*]] = and i32 [[X:%.*]], 4096
+; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[AND]], 0
+; CHECK-NEXT: [[OR:%.*]] = or i32 [[Y:%.*]], 4096
+; CHECK-NEXT: [[TMP1:%.*]] = or i32 [[AND]], [[Y]]
+; CHECK-NEXT: [[SELECT2:%.*]] = select i1 [[CMP]], i32 [[Z:%.*]], i32 [[W:%.*]]
+; CHECK-NEXT: [[RES:%.*]] = mul i32 [[TMP1]], [[SELECT2]]
+; CHECK-NEXT: [[RES2:%.*]] = mul i32 [[RES]], [[OR]]
+; CHECK-NEXT: ret i32 [[RES2]]
+;
+ %and = and i32 %x, 4096
+ %cmp = icmp eq i32 %and, 0
+ %or = or i32 %y, 4096
+ %select = select i1 %cmp, i32 %y, i32 %or
+ %select2 = select i1 %cmp, i32 %z, i32 %w ; to bump up use count of the cmp
+ %res = mul i32 %select, %select2
+ %res2 = mul i32 %res, %or ; to bump up the use count of the or
+ ret i32 %res2
+}
+
+; TODO this increased the number of instructions
+define i32 @no_shift_xor_multiuse_cmp_or(i32 %x, i32 %y, i32 %z, i32 %w) {
+; CHECK-LABEL: @no_shift_xor_multiuse_cmp_or(
+; CHECK-NEXT: [[AND:%.*]] = and i32 [[X:%.*]], 4096
+; CHECK-NEXT: [[CMP:%.*]] = icmp ne i32 [[AND]], 0
+; CHECK-NEXT: [[OR:%.*]] = or i32 [[Y:%.*]], 4096
+; CHECK-NEXT: [[TMP1:%.*]] = xor i32 [[AND]], 4096
+; CHECK-NEXT: [[TMP2:%.*]] = or i32 [[TMP1]], [[Y]]
+; CHECK-NEXT: [[SELECT2:%.*]] = select i1 [[CMP]], i32 [[Z:%.*]], i32 [[W:%.*]]
+; CHECK-NEXT: [[RES:%.*]] = mul i32 [[TMP2]], [[SELECT2]]
+; CHECK-NEXT: [[RES2:%.*]] = mul i32 [[RES]], [[OR]]
+; CHECK-NEXT: ret i32 [[RES2]]
+;
+ %and = and i32 %x, 4096
+ %cmp = icmp ne i32 0, %and
+ %or = or i32 %y, 4096
+ %select = select i1 %cmp, i32 %y, i32 %or
+ %select2 = select i1 %cmp, i32 %z, i32 %w ; to bump up use count of the cmp
+ %res = mul i32 %select, %select2
+ %res2 = mul i32 %res, %or ; to bump up the use count of the or
+ ret i32 %res2
+}
+
+; TODO this increased the number of instructions
+define i32 @shift_xor_multiuse_cmp_or(i32 %x, i32 %y, i32 %z, i32 %w) {
+; CHECK-LABEL: @shift_xor_multiuse_cmp_or(
+; CHECK-NEXT: [[AND:%.*]] = and i32 [[X:%.*]], 4096
+; CHECK-NEXT: [[CMP:%.*]] = icmp ne i32 [[AND]], 0
+; CHECK-NEXT: [[OR:%.*]] = or i32 [[Y:%.*]], 2048
+; CHECK-NEXT: [[TMP1:%.*]] = lshr exact i32 [[AND]], 1
+; CHECK-NEXT: [[TMP2:%.*]] = xor i32 [[TMP1]], 2048
+; CHECK-NEXT: [[TMP3:%.*]] = or i32 [[TMP2]], [[Y]]
+; CHECK-NEXT: [[SELECT2:%.*]] = select i1 [[CMP]], i32 [[Z:%.*]], i32 [[W:%.*]]
+; CHECK-NEXT: [[RES:%.*]] = mul i32 [[TMP3]], [[SELECT2]]
+; CHECK-NEXT: [[RES2:%.*]] = mul i32 [[RES]], [[OR]]
+; CHECK-NEXT: ret i32 [[RES2]]
+;
+ %and = and i32 %x, 4096
+ %cmp = icmp ne i32 0, %and
+ %or = or i32 %y, 2048
+ %select = select i1 %cmp, i32 %y, i32 %or
+ %select2 = select i1 %cmp, i32 %z, i32 %w ; to bump up use count of the cmp
+ %res = mul i32 %select, %select2
+ %res2 = mul i32 %res, %or ; to bump up the use count of the or
+ ret i32 %res2
+}
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