Revert "[InstCombine] Remove the canonicalization of trunc to i1 (llvm#84628)"

cyyself · cyyself · commit e2de1ade1424 · 2024-07-24T16:03:46.000+08:00
This reverts commit 56b3222.
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
@@ -736,18 +736,19 @@ Instruction *InstCombinerImpl::visitTrunc(TruncInst &Trunc) {
 
   if (DestWidth == 1) {
     Value *Zero = Constant::getNullValue(SrcTy);
-
-    Value *X;
-    const APInt *C1;
-    Constant *C2;
-    if (match(Src, m_OneUse(m_Shr(m_Shl(m_Power2(C1), m_Value(X)),
-                                  m_ImmConstant(C2))))) {
-      // trunc ((C1 << X) >> C2) to i1 --> X == (C2-cttz(C1)), where C1 is pow2
-      Constant *Log2C1 = ConstantInt::get(SrcTy, C1->exactLogBase2());
-      Constant *CmpC = ConstantExpr::getSub(C2, Log2C1);
-      return new ICmpInst(ICmpInst::ICMP_EQ, X, CmpC);
+    if (DestTy->isIntegerTy()) {
+      // Canonicalize trunc x to i1 -> icmp ne (and x, 1), 0 (scalar only).
+      // TODO: We canonicalize to more instructions here because we are probably
+      // lacking equivalent analysis for trunc relative to icmp. There may also
+      // be codegen concerns. If those trunc limitations were removed, we could
+      // remove this transform.
+      Value *And = Builder.CreateAnd(Src, ConstantInt::get(SrcTy, 1));
+      return new ICmpInst(ICmpInst::ICMP_NE, And, Zero);
     }
 
+    // For vectors, we do not canonicalize all truncs to icmp, so optimize
+    // patterns that would be covered within visitICmpInst.
+    Value *X;
     Constant *C;
     if (match(Src, m_OneUse(m_LShr(m_Value(X), m_ImmConstant(C))))) {
       // trunc (lshr X, C) to i1 --> icmp ne (and X, C'), 0
diff --git a/llvm/test/Transforms/InstCombine/X86/x86-avx512-inseltpoison.ll b/llvm/test/Transforms/InstCombine/X86/x86-avx512-inseltpoison.ll
diff --git a/llvm/test/Transforms/InstCombine/X86/x86-avx512.ll b/llvm/test/Transforms/InstCombine/X86/x86-avx512.ll
diff --git a/llvm/test/Transforms/InstCombine/apint-shl-trunc.ll b/llvm/test/Transforms/InstCombine/apint-shl-trunc.ll
@@ -3,8 +3,9 @@
 
 define i1 @test0(i39 %X, i39 %A) {
 ; CHECK-LABEL: @test0(
-; CHECK-NEXT:    [[B:%.*]] = lshr i39 [[X:%.*]], [[A:%.*]]
-; CHECK-NEXT:    [[D:%.*]] = trunc i39 [[B]] to i1
+; CHECK-NEXT:    [[TMP1:%.*]] = shl nuw i39 1, [[A:%.*]]
+; CHECK-NEXT:    [[TMP2:%.*]] = and i39 [[TMP1]], [[X:%.*]]
+; CHECK-NEXT:    [[D:%.*]] = icmp ne i39 [[TMP2]], 0
 ; CHECK-NEXT:    ret i1 [[D]]
 ;
   %B = lshr i39 %X, %A
@@ -14,8 +15,9 @@ define i1 @test0(i39 %X, i39 %A) {
 
 define i1 @test1(i799 %X, i799 %A) {
 ; CHECK-LABEL: @test1(
-; CHECK-NEXT:    [[B:%.*]] = lshr i799 [[X:%.*]], [[A:%.*]]
-; CHECK-NEXT:    [[D:%.*]] = trunc i799 [[B]] to i1
+; CHECK-NEXT:    [[TMP1:%.*]] = shl nuw i799 1, [[A:%.*]]
+; CHECK-NEXT:    [[TMP2:%.*]] = and i799 [[TMP1]], [[X:%.*]]
+; CHECK-NEXT:    [[D:%.*]] = icmp ne i799 [[TMP2]], 0
 ; CHECK-NEXT:    ret i1 [[D]]
 ;
   %B = lshr i799 %X, %A
diff --git a/llvm/test/Transforms/InstCombine/cast.ll b/llvm/test/Transforms/InstCombine/cast.ll
@@ -1397,7 +1397,8 @@ define float @sitofp_zext(i16 %a) {
 define i1 @PR23309(i32 %A, i32 %B) {
 ; ALL-LABEL: @PR23309(
 ; ALL-NEXT:    [[SUB:%.*]] = sub i32 [[A:%.*]], [[B:%.*]]
-; ALL-NEXT:    [[TRUNC:%.*]] = trunc i32 [[SUB]] to i1
+; ALL-NEXT:    [[TMP1:%.*]] = and i32 [[SUB]], 1
+; ALL-NEXT:    [[TRUNC:%.*]] = icmp ne i32 [[TMP1]], 0
 ; ALL-NEXT:    ret i1 [[TRUNC]]
 ;
   %add = add i32 %A, -4
@@ -1409,7 +1410,8 @@ define i1 @PR23309(i32 %A, i32 %B) {
 define i1 @PR23309v2(i32 %A, i32 %B) {
 ; ALL-LABEL: @PR23309v2(
 ; ALL-NEXT:    [[SUB:%.*]] = add i32 [[A:%.*]], [[B:%.*]]
-; ALL-NEXT:    [[TRUNC:%.*]] = trunc i32 [[SUB]] to i1
+; ALL-NEXT:    [[TMP1:%.*]] = and i32 [[SUB]], 1
+; ALL-NEXT:    [[TRUNC:%.*]] = icmp ne i32 [[TMP1]], 0
 ; ALL-NEXT:    ret i1 [[TRUNC]]
 ;
   %add = add i32 %A, -4
diff --git a/llvm/test/Transforms/InstCombine/catchswitch-phi.ll b/llvm/test/Transforms/InstCombine/catchswitch-phi.ll
@@ -24,11 +24,11 @@ define void @test0(i1 %c1) personality ptr @__gxx_wasm_personality_v0 {
 ; CHECK:       bb1:
 ; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr inbounds i8, ptr [[TMP0]], i32 4
 ; CHECK-NEXT:    invoke void @foo()
-; CHECK-NEXT:            to label [[BB3:%.*]] unwind label [[BB4:%.*]]
+; CHECK-NEXT:    to label [[BB3:%.*]] unwind label [[BB4:%.*]]
 ; CHECK:       bb2:
 ; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr inbounds i8, ptr [[TMP0]], i32 4
 ; CHECK-NEXT:    invoke void @foo()
-; CHECK-NEXT:            to label [[BB3]] unwind label [[BB4]]
+; CHECK-NEXT:    to label [[BB3]] unwind label [[BB4]]
 ; CHECK:       bb3:
 ; CHECK-NEXT:    unreachable
 ; CHECK:       bb4:
@@ -37,7 +37,7 @@ define void @test0(i1 %c1) personality ptr @__gxx_wasm_personality_v0 {
 ; CHECK:       bb5:
 ; CHECK-NEXT:    [[TMP5:%.*]] = catchpad within [[TMP4]] [ptr null]
 ; CHECK-NEXT:    invoke void @foo() [ "funclet"(token [[TMP5]]) ]
-; CHECK-NEXT:            to label [[BB6:%.*]] unwind label [[BB7]]
+; CHECK-NEXT:    to label [[BB6:%.*]] unwind label [[BB7]]
 ; CHECK:       bb6:
 ; CHECK-NEXT:    unreachable
 ; CHECK:       bb7:
@@ -89,10 +89,10 @@ define void @test1() personality ptr @__gxx_wasm_personality_v0 {
 ; CHECK-LABEL: @test1(
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    invoke void @foo()
-; CHECK-NEXT:            to label [[INVOKE_CONT:%.*]] unwind label [[CATCH_DISPATCH1:%.*]]
+; CHECK-NEXT:    to label [[INVOKE_CONT:%.*]] unwind label [[CATCH_DISPATCH1:%.*]]
 ; CHECK:       invoke.cont:
 ; CHECK-NEXT:    [[CALL:%.*]] = invoke i32 @baz()
-; CHECK-NEXT:            to label [[INVOKE_CONT1:%.*]] unwind label [[CATCH_DISPATCH:%.*]]
+; CHECK-NEXT:    to label [[INVOKE_CONT1:%.*]] unwind label [[CATCH_DISPATCH:%.*]]
 ; CHECK:       invoke.cont1:
 ; CHECK-NEXT:    [[TOBOOL_NOT:%.*]] = icmp eq i32 [[CALL]], 0
 ; CHECK-NEXT:    br i1 [[TOBOOL_NOT]], label [[IF_END:%.*]], label [[IF_THEN:%.*]]
@@ -101,7 +101,7 @@ define void @test1() personality ptr @__gxx_wasm_personality_v0 {
 ; CHECK:       if.end:
 ; CHECK-NEXT:    [[AP_0:%.*]] = phi i8 [ 1, [[IF_THEN]] ], [ 0, [[INVOKE_CONT1]] ]
 ; CHECK-NEXT:    invoke void @foo()
-; CHECK-NEXT:            to label [[INVOKE_CONT2:%.*]] unwind label [[CATCH_DISPATCH]]
+; CHECK-NEXT:    to label [[INVOKE_CONT2:%.*]] unwind label [[CATCH_DISPATCH]]
 ; CHECK:       invoke.cont2:
 ; CHECK-NEXT:    br label [[TRY_CONT:%.*]]
 ; CHECK:       catch.dispatch:
@@ -114,16 +114,17 @@ define void @test1() personality ptr @__gxx_wasm_personality_v0 {
 ; CHECK-NEXT:    catchret from [[TMP1]] to label [[TRY_CONT]]
 ; CHECK:       rethrow:
 ; CHECK-NEXT:    invoke void @llvm.wasm.rethrow() #[[ATTR0:[0-9]+]] [ "funclet"(token [[TMP1]]) ]
-; CHECK-NEXT:            to label [[UNREACHABLE:%.*]] unwind label [[CATCH_DISPATCH1]]
+; CHECK-NEXT:    to label [[UNREACHABLE:%.*]] unwind label [[CATCH_DISPATCH1]]
 ; CHECK:       catch.dispatch1:
 ; CHECK-NEXT:    [[AP_2:%.*]] = phi i8 [ [[AP_1]], [[CATCH_DISPATCH]] ], [ [[AP_1]], [[RETHROW]] ], [ 0, [[ENTRY:%.*]] ]
 ; CHECK-NEXT:    [[TMP2:%.*]] = catchswitch within none [label %catch.start1] unwind to caller
 ; CHECK:       catch.start1:
 ; CHECK-NEXT:    [[TMP3:%.*]] = catchpad within [[TMP2]] [ptr null]
-; CHECK-NEXT:    [[TOBOOL1_NOT:%.*]] = trunc i8 [[AP_2]] to i1
+; CHECK-NEXT:    [[TMP0:%.*]] = and i8 [[AP_2]], 1
+; CHECK-NEXT:    [[TOBOOL1_NOT:%.*]] = icmp eq i8 [[TMP0]], 0
 ; CHECK-NEXT:    br i1 [[TOBOOL1_NOT]], label [[IF_END1:%.*]], label [[IF_THEN1:%.*]]
 ; CHECK:       if.then1:
-; CHECK-NEXT:    br label [[IF_THEN1]]
+; CHECK-NEXT:    br label [[IF_END1]]
 ; CHECK:       if.end1:
 ; CHECK-NEXT:    catchret from [[TMP3]] to label [[TRY_CONT]]
 ; CHECK:       try.cont:
diff --git a/llvm/test/Transforms/InstCombine/icmp-mul-and.ll b/llvm/test/Transforms/InstCombine/icmp-mul-and.ll
@@ -267,10 +267,10 @@ define i1 @pr51551_neg1(i32 %x, i32 %y) {
 
 define i1 @pr51551_neg2(i32 %x, i32 %y) {
 ; CHECK-LABEL: @pr51551_neg2(
-; CHECK-NEXT:    [[TMP1:%.*]] = trunc i32 [[Y:%.*]] to i1
+; CHECK-NEXT:    [[TMP1:%.*]] = and i32 [[Y:%.*]], 1
+; CHECK-NEXT:    [[DOTNOT:%.*]] = icmp eq i32 [[TMP1]], 0
 ; CHECK-NEXT:    [[TMP2:%.*]] = and i32 [[X:%.*]], 7
 ; CHECK-NEXT:    [[CMP1:%.*]] = icmp eq i32 [[TMP2]], 0
-; CHECK-NEXT:    [[DOTNOT:%.*]] = xor i1 [[TMP1]], true
 ; CHECK-NEXT:    [[CMP:%.*]] = select i1 [[DOTNOT]], i1 true, i1 [[CMP1]]
 ; CHECK-NEXT:    ret i1 [[CMP]]
 ;
diff --git a/llvm/test/Transforms/InstCombine/icmp-mul-zext.ll b/llvm/test/Transforms/InstCombine/icmp-mul-zext.ll
@@ -128,12 +128,12 @@ define i1 @PR46561(i1 %a, i1 %x, i1 %y, i8 %z) {
 ; CHECK-NEXT:    br i1 [[A:%.*]], label [[COND_TRUE:%.*]], label [[END:%.*]]
 ; CHECK:       cond.true:
 ; CHECK-NEXT:    [[MULBOOL:%.*]] = and i1 [[X:%.*]], [[Y:%.*]]
-; CHECK-NEXT:    [[TMP1:%.*]] = trunc i8 [[Z:%.*]] to i1
+; CHECK-NEXT:    [[TMP0:%.*]] = and i8 [[Z:%.*]], 1
+; CHECK-NEXT:    [[TMP1:%.*]] = icmp eq i8 [[TMP0]], 0
 ; CHECK-NEXT:    [[TMP2:%.*]] = xor i1 [[MULBOOL]], [[TMP1]]
-; CHECK-NEXT:    [[TMP3:%.*]] = xor i1 [[TMP2]], true
 ; CHECK-NEXT:    br label [[END]]
 ; CHECK:       end:
-; CHECK-NEXT:    [[P:%.*]] = phi i1 [ [[TMP3]], [[COND_TRUE]] ], [ false, [[ENTRY:%.*]] ]
+; CHECK-NEXT:    [[P:%.*]] = phi i1 [ [[TMP2]], [[COND_TRUE]] ], [ false, [[ENTRY:%.*]] ]
 ; CHECK-NEXT:    ret i1 [[P]]
 ;
 entry:
diff --git a/llvm/test/Transforms/InstCombine/mul-masked-bits.ll b/llvm/test/Transforms/InstCombine/mul-masked-bits.ll
@@ -214,8 +214,9 @@ define i64 @scalar_mul_bit_x0_y0_uses(i64 %x, i64 %y) {
 define i64 @scalar_mul_bit_x0_y1(i64 %x, i64 %y) {
 ; CHECK-LABEL: @scalar_mul_bit_x0_y1(
 ; CHECK-NEXT:    [[AND2:%.*]] = and i64 [[Y:%.*]], 2
-; CHECK-NEXT:    [[TMP1:%.*]] = trunc i64 [[X:%.*]] to i1
-; CHECK-NEXT:    [[MUL:%.*]] = select i1 [[TMP1]], i64 [[AND2]], i64 0
+; CHECK-NEXT:    [[TMP1:%.*]] = and i64 [[X:%.*]], 1
+; CHECK-NEXT:    [[DOTNOT:%.*]] = icmp eq i64 [[TMP1]], 0
+; CHECK-NEXT:    [[MUL:%.*]] = select i1 [[DOTNOT]], i64 0, i64 [[AND2]]
 ; CHECK-NEXT:    ret i64 [[MUL]]
 ;
   %and1 = and i64 %x, 1
@@ -227,8 +228,9 @@ define i64 @scalar_mul_bit_x0_y1(i64 %x, i64 %y) {
 define i64 @scalar_mul_bit_x0_yC(i64 %x, i64 %y, i64 %c) {
 ; CHECK-LABEL: @scalar_mul_bit_x0_yC(
 ; CHECK-NEXT:    [[AND2:%.*]] = and i64 [[Y:%.*]], [[C:%.*]]
-; CHECK-NEXT:    [[TMP1:%.*]] = trunc i64 [[X:%.*]] to i1
-; CHECK-NEXT:    [[MUL:%.*]] = select i1 [[TMP1]], i64 [[AND2]], i64 0
+; CHECK-NEXT:    [[TMP1:%.*]] = and i64 [[X:%.*]], 1
+; CHECK-NEXT:    [[DOTNOT:%.*]] = icmp eq i64 [[TMP1]], 0
+; CHECK-NEXT:    [[MUL:%.*]] = select i1 [[DOTNOT]], i64 0, i64 [[AND2]]
 ; CHECK-NEXT:    ret i64 [[MUL]]
 ;
   %and1 = and i64 %x, 1
diff --git a/llvm/test/Transforms/InstCombine/mul.ll b/llvm/test/Transforms/InstCombine/mul.ll
@@ -684,8 +684,9 @@ define <2 x i32> @signbit_mul_vec_commute(<2 x i32> %a, <2 x i32> %b) {
 
 define i32 @lowbit_mul(i32 %a, i32 %b) {
 ; CHECK-LABEL: @lowbit_mul(
-; CHECK-NEXT:    [[TMP1:%.*]] = trunc i32 [[A:%.*]] to i1
-; CHECK-NEXT:    [[E:%.*]] = select i1 [[TMP1]], i32 [[B:%.*]], i32 0
+; CHECK-NEXT:    [[TMP1:%.*]] = and i32 [[A:%.*]], 1
+; CHECK-NEXT:    [[DOTNOT:%.*]] = icmp eq i32 [[TMP1]], 0
+; CHECK-NEXT:    [[E:%.*]] = select i1 [[DOTNOT]], i32 0, i32 [[B:%.*]]
 ; CHECK-NEXT:    ret i32 [[E]]
 ;
   %d = and i32 %a, 1
diff --git a/llvm/test/Transforms/InstCombine/phi.ll b/llvm/test/Transforms/InstCombine/phi.ll
@@ -137,8 +137,8 @@ define i32 @test6(i16 %A, i1 %b) {
 ; CHECK:       BB1:
 ; CHECK-NEXT:    br label [[BB2]]
 ; CHECK:       BB2:
-; CHECK-NEXT:    [[C:%.*]] = zext i16 [[A:%.*]] to i32
-; CHECK-NEXT:    ret i32 [[C]]
+; CHECK-NEXT:    [[B:%.*]] = zext i16 [[A:%.*]] to i32
+; CHECK-NEXT:    ret i32 [[B]]
 ;
 BB0:
   %X = zext i16 %A to i32
@@ -150,8 +150,8 @@ BB1:
 
 BB2:
   ;; Suck casts into phi
-  %c = phi i32 [ %X, %BB0 ], [ %Y, %BB1 ]
-  ret i32 %c
+  %B = phi i32 [ %X, %BB0 ], [ %Y, %BB1 ]
+  ret i32 %B
 }
 
 define i32 @test_dead_cycle(i32 %A, i1 %cond) {
@@ -253,8 +253,8 @@ define ptr @test8(ptr %A, i1 %b) {
 ; CHECK:       BB1:
 ; CHECK-NEXT:    br label [[BB2]]
 ; CHECK:       BB2:
-; CHECK-NEXT:    [[C:%.*]] = getelementptr i8, ptr [[A:%.*]], i64 4
-; CHECK-NEXT:    ret ptr [[C]]
+; CHECK-NEXT:    [[B:%.*]] = getelementptr i8, ptr [[A:%.*]], i64 4
+; CHECK-NEXT:    ret ptr [[B]]
 ;
 BB0:
   %X = getelementptr inbounds { i32, i32 }, ptr %A, i32 0, i32 1
@@ -266,8 +266,8 @@ BB1:
 
 BB2:
   ;; Suck GEPs into phi
-  %c = phi ptr [ %X, %BB0 ], [ %Y, %BB1 ]
-  ret ptr %c
+  %B = phi ptr [ %X, %BB0 ], [ %Y, %BB1 ]
+  ret ptr %B
 }
 
 define i32 @test9(ptr %A, ptr %B) {
@@ -510,8 +510,9 @@ define i64 @test15b(i64 %A, i1 %b) {
 ; CHECK-NEXT:    [[Y_OFF0:%.*]] = phi i64 [ [[A]], [[ENTRY]] ], [ [[C]], [[ONE]] ]
 ; CHECK-NEXT:    [[Y_OFF64]] = phi i64 [ [[A]], [[ENTRY]] ], [ 0, [[ONE]] ]
 ; CHECK-NEXT:    [[D:%.*]] = call i64 @test15a(i64 [[Y_OFF64]])
-; CHECK-NEXT:    [[D1:%.*]] = trunc i64 [[D]] to i1
-; CHECK-NEXT:    br i1 [[D1]], label [[ONE]], label [[END:%.*]]
+; CHECK-NEXT:    [[TMP0:%.*]] = and i64 [[D]], 1
+; CHECK-NEXT:    [[D1_NOT:%.*]] = icmp eq i64 [[TMP0]], 0
+; CHECK-NEXT:    br i1 [[D1_NOT]], label [[END:%.*]], label [[ONE]]
 ; CHECK:       end:
 ; CHECK-NEXT:    ret i64 [[Y_OFF0]]
 ;
diff --git a/llvm/test/Transforms/InstCombine/ptr-int-cast.ll b/llvm/test/Transforms/InstCombine/ptr-int-cast.ll
@@ -6,7 +6,8 @@ define i1 @test1(ptr %x) nounwind {
 ; CHECK-LABEL: @test1(
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    [[TMP0:%.*]] = ptrtoint ptr [[X:%.*]] to i64
-; CHECK-NEXT:    [[TMP2:%.*]] = trunc i64 [[TMP0]] to i1
+; CHECK-NEXT:    [[TMP1:%.*]] = and i64 [[TMP0]], 1
+; CHECK-NEXT:    [[TMP2:%.*]] = icmp ne i64 [[TMP1]], 0
 ; CHECK-NEXT:    ret i1 [[TMP2]]
 ;
 entry:
diff --git a/llvm/test/Transforms/PhaseOrdering/X86/merge-functions.ll b/llvm/test/Transforms/PhaseOrdering/X86/merge-functions.ll
@@ -14,7 +14,8 @@ define i1 @test1(i32 %c) {
 ; CHECK-NEXT:    [[TMP0:%.*]] = icmp ult i32 [[SWITCH_TABLEIDX]], 20
 ; CHECK-NEXT:    [[SWITCH_CAST:%.*]] = trunc i32 [[SWITCH_TABLEIDX]] to i20
 ; CHECK-NEXT:    [[SWITCH_DOWNSHIFT:%.*]] = lshr i20 -490991, [[SWITCH_CAST]]
-; CHECK-NEXT:    [[SWITCH_MASKED:%.*]] = trunc i20 [[SWITCH_DOWNSHIFT]] to i1
+; CHECK-NEXT:    [[TMP1:%.*]] = and i20 [[SWITCH_DOWNSHIFT]], 1
+; CHECK-NEXT:    [[SWITCH_MASKED:%.*]] = icmp ne i20 [[TMP1]], 0
 ; CHECK-NEXT:    [[I_0:%.*]] = select i1 [[TMP0]], i1 [[SWITCH_MASKED]], i1 false
 ; CHECK-NEXT:    ret i1 [[I_0]]
 ;
