Revert "[DAG] Fold (umin (sub a b) a) -> (usubo a b); (select usubo.1 a usubo.0)"#167854
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Revert "[DAG] Fold (umin (sub a b) a) -> (usubo a b); (select usubo.1 a usubo.0)"#167854
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… a usubo…" This reverts commit 1f58cbe.
llvmbot
added
backend:AArch64
backend:X86
llvm:SelectionDAG
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@llvm/pr-subscribers-llvm-selectiondag @llvm/pr-subscribers-backend-x86 Author: Simon Pilgrim (RKSimon) ChangesReverts llvm/llvm-project#161651 due to downstream bad codegen reports Full diff: https://github.com/llvm/llvm-project/pull/167854.diff 3 Files Affected:
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index d9d3a3ec01757..df353c4d91b1a 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -6219,25 +6219,6 @@ SDValue DAGCombiner::visitIMINMAX(SDNode *N) {
SDLoc(N), VT, N0, N1))
return SD;
- if (TLI.isOperationLegalOrCustom(ISD::USUBO, VT) &&
- !TLI.isOperationLegalOrCustom(ISD::UMIN, VT)) {
- SDValue B;
-
- // (umin (sub a, b), a) -> (usubo a, b); (select usubo.1, a, usubo.0)
- if (sd_match(N0, m_Sub(m_Specific(N1), m_Value(B)))) {
- SDVTList VTs = DAG.getVTList(VT, getSetCCResultType(VT));
- SDValue USO = DAG.getNode(ISD::USUBO, DL, VTs, N1, B);
- return DAG.getSelect(DL, VT, USO.getValue(1), N1, USO.getValue(0));
- }
-
- // (umin a, (sub a, b)) -> (usubo a, b); (select usubo.1, a, usubo.0)
- if (sd_match(N1, m_Sub(m_Specific(N0), m_Value(B)))) {
- SDVTList VTs = DAG.getVTList(VT, getSetCCResultType(VT));
- SDValue USO = DAG.getNode(ISD::USUBO, DL, VTs, N0, B);
- return DAG.getSelect(DL, VT, USO.getValue(1), N0, USO.getValue(0));
- }
- }
-
// Simplify the operands using demanded-bits information.
if (SimplifyDemandedBits(SDValue(N, 0)))
return SDValue(N, 0);
diff --git a/llvm/test/CodeGen/AArch64/umin-sub-to-usubo-select-combine.ll b/llvm/test/CodeGen/AArch64/umin-sub-to-usubo-select-combine.ll
deleted file mode 100644
index fe3eee06db65e..0000000000000
--- a/llvm/test/CodeGen/AArch64/umin-sub-to-usubo-select-combine.ll
+++ /dev/null
@@ -1,151 +0,0 @@
-; RUN: llc < %s -mtriple=aarch64 | FileCheck %s
-
-; GitHub issue #161036
-
-; Positive test : umin(sub(a,b),a) with scalar types should be folded
-define i64 @underflow_compare_fold_i64(i64 %a, i64 %b) {
-; CHECK-LABEL: underflow_compare_fold_i64
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: subs x8, x0, x1
-; CHECK-NEXT: csel x0, x0, x8, lo
-; CHECK-NEXT: ret
- %sub = sub i64 %a, %b
- %cond = tail call i64 @llvm.umin.i64(i64 %sub, i64 %a)
- ret i64 %cond
-}
-
-; Positive test : umin(a,sub(a,b)) with scalar types should be folded
-define i64 @underflow_compare_fold_i64_commute(i64 %a, i64 %b) {
-; CHECK-LABEL: underflow_compare_fold_i64_commute
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: subs x8, x0, x1
-; CHECK-NEXT: csel x0, x0, x8, lo
-; CHECK-NEXT: ret
- %sub = sub i64 %a, %b
- %cond = tail call i64 @llvm.umin.i64(i64 %a, i64 %sub)
- ret i64 %cond
-}
-
-; Positive test : multi-use is OK since the sub instruction still runs once
-define i64 @underflow_compare_fold_i64_multi_use(i64 %a, i64 %b, ptr addrspace(1) %ptr) {
-; CHECK-LABEL: underflow_compare_fold_i64_multi_use
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: subs x8, x0, x1
-; CHECK-NEXT: csel x0, x0, x8, lo
-; CHECK-NEXT: str x8, [x2]
-; CHECK-NEXT: ret
- %sub = sub i64 %a, %b
- store i64 %sub, ptr addrspace(1) %ptr
- %cond = call i64 @llvm.umin.i64(i64 %sub, i64 %a)
- ret i64 %cond
-}
-
-; Positive test : i32
-define i32 @underflow_compare_fold_i32(i32 %a, i32 %b) {
-; CHECK-LABEL: underflow_compare_fold_i32
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: subs w8, w0, w1
-; CHECK-NEXT: csel w0, w0, w8, lo
-; CHECK-NEXT: ret
- %sub = sub i32 %a, %b
- %cond = tail call i32 @llvm.umin.i32(i32 %sub, i32 %a)
- ret i32 %cond
-}
-
-; Positive test : i32
-define i32 @underflow_compare_fold_i32_commute(i32 %a, i32 %b) {
-; CHECK-LABEL: underflow_compare_fold_i32_commute
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: subs w8, w0, w1
-; CHECK-NEXT: csel w0, w0, w8, lo
-; CHECK-NEXT: ret
- %sub = sub i32 %a, %b
- %cond = tail call i32 @llvm.umin.i32(i32 %a, i32 %sub)
- ret i32 %cond
-}
-
-; Positive test : i32
-define i32 @underflow_compare_fold_i32_multi_use(i32 %a, i32 %b, ptr addrspace(1) %ptr) {
-; CHECK-LABEL: underflow_compare_fold_i32_multi_use
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: subs w8, w0, w1
-; CHECK-NEXT: csel w0, w0, w8, lo
-; CHECK-NEXT: str w8, [x2]
-; CHECK-NEXT: ret
- %sub = sub i32 %a, %b
- store i32 %sub, ptr addrspace(1) %ptr
- %cond = call i32 @llvm.umin.i32(i32 %sub, i32 %a)
- ret i32 %cond
-}
-
-; Negative test : i16
-define i16 @underflow_compare_fold_i16(i16 %a, i16 %b) {
-; CHECK-LABEL: underflow_compare_fold_i16
-; CHECK-LABEL: %bb.0:
-; CHECK-LABEL: sub w8, w0, w1
-; CHECK-LABEL: and w9, w0, #0xffff
-; CHECK-LABEL: and w8, w8, #0xffff
-; CHECK-LABEL: cmp w8, w9
-; CHECK-LABEL: csel w0, w8, w9, lo
-; CHECK-LABEL: ret
- %sub = sub i16 %a, %b
- %cond = tail call i16 @llvm.umin.i16(i16 %sub, i16 %a)
- ret i16 %cond
-}
-
-; Negative test : i16
-define i16 @underflow_compare_fold_i16_commute(i16 %a, i16 %b) {
-; CHECK-LABEL: underflow_compare_fold_i16_commute
-; CHECK-LABEL: %bb.0:
-; CHECK-LABEL: sub w8, w0, w1
-; CHECK-LABEL: and w9, w0, #0xffff
-; CHECK-LABEL: and w8, w8, #0xffff
-; CHECK-LABEL: cmp w9, w8
-; CHECK-LABEL: csel w0, w9, w8, lo
-; CHECK-LABEL: ret
- %sub = sub i16 %a, %b
- %cond = tail call i16 @llvm.umin.i16(i16 %a, i16 %sub)
- ret i16 %cond
-}
-
-; Negative test : i16
-define i16 @underflow_compare_fold_i16_multi_use(i16 %a, i16 %b, ptr addrspace(1) %ptr) {
-; CHECK-LABEL: underflow_compare_fold_i16_multi_use
-; CHECK-LABEL: %bb.0:
-; CHECK-LABEL: sub w8, w0, w1
-; CHECK-LABEL: and w9, w0, #0xffff
-; CHECK-LABEL: and w10, w8, #0xffff
-; CHECK-LABEL: strh w8, [x2]
-; CHECK-LABEL: cmp w10, w9
-; CHECK-LABEL: csel w0, w10, w9, lo
-; CHECK-LABEL: ret
- %sub = sub i16 %a, %b
- store i16 %sub, ptr addrspace(1) %ptr
- %cond = call i16 @llvm.umin.i16(i16 %sub, i16 %a)
- ret i16 %cond
-}
-
-; Negative test, vector types : umin(sub(a,b),a) but with vectors
-define <16 x i8> @underflow_compare_dontfold_vectors(<16 x i8> %a, <16 x i8> %b) {
-; CHECK-LABEL: underflow_compare_dontfold_vectors
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: sub v1.16b, v0.16b, v1.16b
-; CHECK-NEXT: umin v0.16b, v1.16b, v0.16b
-; CHECK-NEXT: ret
- %sub = sub <16 x i8> %a, %b
- %cond = tail call <16 x i8> @llvm.umin.v16i8(<16 x i8> %sub, <16 x i8> %a)
- ret <16 x i8> %cond
-}
-
-; Negative test, pattern mismatch : umin(add(a,b),a)
-define i64 @umin_add(i64 %a, i64 %b) {
-; CHECK-LABEL: umin_add
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: add x8, x0, x1
-; CHECK-NEXT: cmp x8, x0
-; CHECK-NEXT: csel x0, x8, x0, lo
-; CHECK-NEXT: ret
- %add = add i64 %a, %b
- %cond = tail call i64 @llvm.umin.i64(i64 %add, i64 %a)
- ret i64 %cond
-}
diff --git a/llvm/test/CodeGen/X86/umin-sub-to-usubo-select-combine.ll b/llvm/test/CodeGen/X86/umin-sub-to-usubo-select-combine.ll
deleted file mode 100644
index e9756b411eb2c..0000000000000
--- a/llvm/test/CodeGen/X86/umin-sub-to-usubo-select-combine.ll
+++ /dev/null
@@ -1,156 +0,0 @@
-; RUN: llc < %s -mtriple=x86_64 | FileCheck %s
-
-; GitHub issue #161036
-
-; Positive test : umin(sub(a,b),a) with scalar types should be folded
-define i64 @underflow_compare_fold_i64(i64 %a, i64 %b) {
-; CHECK-LABEL: underflow_compare_fold_i64
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: movq %rdi, %rax
-; CHECK-NEXT: subq %rsi, %rax
-; CHECK-NEXT: cmovbq %rdi, %rax
-; CHECK-NEXT: retq
- %sub = sub i64 %a, %b
- %cond = tail call i64 @llvm.umin.i64(i64 %sub, i64 %a)
- ret i64 %cond
-}
-
-; Positive test : umin(a,sub(a,b)) with scalar types should be folded
-define i64 @underflow_compare_fold_i64_commute(i64 %a, i64 %b) {
-; CHECK-LABEL: underflow_compare_fold_i64_commute
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: movq %rdi, %rax
-; CHECK-NEXT: subq %rsi, %rax
-; CHECK-NEXT: cmovbq %rdi, %rax
-; CHECK-NEXT: retq
- %sub = sub i64 %a, %b
- %cond = tail call i64 @llvm.umin.i64(i64 %a, i64 %sub)
- ret i64 %cond
-}
-
-; Positive test : multi-use is OK since the sub instruction still runs once
-define i64 @underflow_compare_fold_i64_multi_use(i64 %a, i64 %b, ptr addrspace(1) %ptr) {
-; CHECK-LABEL: underflow_compare_fold_i64_multi_use
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: movq %rdi, %rax
-; CHECK-NEXT: subq %rsi, %rax
-; CHECK-NEXT: movq %rax, (%rdx)
-; CHECK-NEXT: cmovbq %rdi, %rax
-; CHECK-NEXT: retq
- %sub = sub i64 %a, %b
- store i64 %sub, ptr addrspace(1) %ptr
- %cond = call i64 @llvm.umin.i64(i64 %sub, i64 %a)
- ret i64 %cond
-}
-
-; Positive test : i32
-define i32 @underflow_compare_fold_i32(i32 %a, i32 %b) {
-; CHECK-LABEL: underflow_compare_fold_i32
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: movl %edi, %eax
-; CHECK-NEXT: subl %esi, %eax
-; CHECK-NEXT: cmovbl %edi, %eax
-; CHECK-NEXT: retq
- %sub = sub i32 %a, %b
- %cond = tail call i32 @llvm.umin.i32(i32 %sub, i32 %a)
- ret i32 %cond
-}
-
-; Positive test : i32
-define i32 @underflow_compare_fold_i32_commute(i32 %a, i32 %b) {
-; CHECK-LABEL: underflow_compare_fold_i32_commute
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: movl %edi, %eax
-; CHECK-NEXT: subl %esi, %eax
-; CHECK-NEXT: cmovbl %edi, %eax
-; CHECK-NEXT: retq
- %sub = sub i32 %a, %b
- %cond = tail call i32 @llvm.umin.i32(i32 %a, i32 %sub)
- ret i32 %cond
-}
-
-; Positive test : i32
-define i32 @underflow_compare_fold_i32_multi_use(i32 %a, i32 %b, ptr addrspace(1) %ptr) {
-; CHECK-LABEL: underflow_compare_fold_i32_multi_use
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: movl %edi, %eax
-; CHECK-NEXT: subl %esi, %eax
-; CHECK-NEXT: movl %eax, (%rdx)
-; CHECK-NEXT: cmovbl %edi, %eax
-; CHECK-NEXT: retq
- %sub = sub i32 %a, %b
- store i32 %sub, ptr addrspace(1) %ptr
- %cond = call i32 @llvm.umin.i32(i32 %sub, i32 %a)
- ret i32 %cond
-}
-
-; Positive test : i16
-define i16 @underflow_compare_fold_i16(i16 %a, i16 %b) {
-; CHECK-LABEL: underflow_compare_fold_i16
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: movl %edi, %eax
-; CHECK-NEXT: subw %si, %ax
-; CHECK-NEXT: cmovbl %edi, %eax
-; CHECK-NEXT: # kill: def $ax killed $ax killed $eax
-; CHECK-NEXT: retq
- %sub = sub i16 %a, %b
- %cond = tail call i16 @llvm.umin.i16(i16 %sub, i16 %a)
- ret i16 %cond
-}
-
-; Positive test : i16
-define i16 @underflow_compare_fold_i16_commute(i16 %a, i16 %b) {
-; CHECK-LABEL: underflow_compare_fold_i16_commute
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: movl %edi, %eax
-; CHECK-NEXT: subw %si, %ax
-; CHECK-NEXT: cmovbl %edi, %eax
-; CHECK-NEXT: # kill: def $ax killed $ax killed $eax
-; CHECK-NEXT: retq
- %sub = sub i16 %a, %b
- %cond = tail call i16 @llvm.umin.i16(i16 %a, i16 %sub)
- ret i16 %cond
-}
-
-; Positive test : i16
-define i16 @underflow_compare_fold_i16_multi_use(i16 %a, i16 %b, ptr addrspace(1) %ptr) {
-; CHECK-LABEL: underflow_compare_fold_i16_multi_use
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: movl %edi, %eax
-; CHECK-NEXT: subw %si, %ax
-; CHECK-NEXT: movw %ax, (%rdx)
-; CHECK-NEXT: cmovbl %edi, %eax
-; CHECK-NEXT: # kill: def $ax killed $ax killed $eax
-; CHECK-NEXT: retq
- %sub = sub i16 %a, %b
- store i16 %sub, ptr addrspace(1) %ptr
- %cond = call i16 @llvm.umin.i16(i16 %sub, i16 %a)
- ret i16 %cond
-}
-
-
-; Negative test, vector types : umin(sub(a,b),a) but with vectors
-define <16 x i8> @underflow_compare_dontfold_vectors(<16 x i8> %a, <16 x i8> %b) {
-; CHECK-LABEL: underflow_compare_dontfold_vectors
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: movdqa %xmm0, %xmm2
-; CHECK-NEXT: psubb %xmm1, %xmm2
-; CHECK-NEXT: pminub %xmm2, %xmm0
-; CHECK-NEXT: retq
- %sub = sub <16 x i8> %a, %b
- %cond = tail call <16 x i8> @llvm.umin.v16i8(<16 x i8> %sub, <16 x i8> %a)
- ret <16 x i8> %cond
-}
-
-; Negative test, pattern mismatch : umin(add(a,b),a)
-define i64 @umin_add(i64 %a, i64 %b) {
-; CHECK-LABEL: umin_add
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: leaq (%rsi,%rdi), %rax
-; CHECK-NEXT: cmpq %rdi, %rax
-; CHECK-NEXT: cmovaeq %rdi, %rax
-; CHECK-NEXT: retq
- %add = add i64 %a, %b
- %cond = tail call i64 @llvm.umin.i64(i64 %add, i64 %a)
- ret i64 %cond
-}
|
Member
|
@llvm/pr-subscribers-backend-aarch64 Author: Simon Pilgrim (RKSimon) ChangesReverts llvm/llvm-project#161651 due to downstream bad codegen reports Full diff: https://github.com/llvm/llvm-project/pull/167854.diff 3 Files Affected:
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index d9d3a3ec01757..df353c4d91b1a 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -6219,25 +6219,6 @@ SDValue DAGCombiner::visitIMINMAX(SDNode *N) {
SDLoc(N), VT, N0, N1))
return SD;
- if (TLI.isOperationLegalOrCustom(ISD::USUBO, VT) &&
- !TLI.isOperationLegalOrCustom(ISD::UMIN, VT)) {
- SDValue B;
-
- // (umin (sub a, b), a) -> (usubo a, b); (select usubo.1, a, usubo.0)
- if (sd_match(N0, m_Sub(m_Specific(N1), m_Value(B)))) {
- SDVTList VTs = DAG.getVTList(VT, getSetCCResultType(VT));
- SDValue USO = DAG.getNode(ISD::USUBO, DL, VTs, N1, B);
- return DAG.getSelect(DL, VT, USO.getValue(1), N1, USO.getValue(0));
- }
-
- // (umin a, (sub a, b)) -> (usubo a, b); (select usubo.1, a, usubo.0)
- if (sd_match(N1, m_Sub(m_Specific(N0), m_Value(B)))) {
- SDVTList VTs = DAG.getVTList(VT, getSetCCResultType(VT));
- SDValue USO = DAG.getNode(ISD::USUBO, DL, VTs, N0, B);
- return DAG.getSelect(DL, VT, USO.getValue(1), N0, USO.getValue(0));
- }
- }
-
// Simplify the operands using demanded-bits information.
if (SimplifyDemandedBits(SDValue(N, 0)))
return SDValue(N, 0);
diff --git a/llvm/test/CodeGen/AArch64/umin-sub-to-usubo-select-combine.ll b/llvm/test/CodeGen/AArch64/umin-sub-to-usubo-select-combine.ll
deleted file mode 100644
index fe3eee06db65e..0000000000000
--- a/llvm/test/CodeGen/AArch64/umin-sub-to-usubo-select-combine.ll
+++ /dev/null
@@ -1,151 +0,0 @@
-; RUN: llc < %s -mtriple=aarch64 | FileCheck %s
-
-; GitHub issue #161036
-
-; Positive test : umin(sub(a,b),a) with scalar types should be folded
-define i64 @underflow_compare_fold_i64(i64 %a, i64 %b) {
-; CHECK-LABEL: underflow_compare_fold_i64
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: subs x8, x0, x1
-; CHECK-NEXT: csel x0, x0, x8, lo
-; CHECK-NEXT: ret
- %sub = sub i64 %a, %b
- %cond = tail call i64 @llvm.umin.i64(i64 %sub, i64 %a)
- ret i64 %cond
-}
-
-; Positive test : umin(a,sub(a,b)) with scalar types should be folded
-define i64 @underflow_compare_fold_i64_commute(i64 %a, i64 %b) {
-; CHECK-LABEL: underflow_compare_fold_i64_commute
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: subs x8, x0, x1
-; CHECK-NEXT: csel x0, x0, x8, lo
-; CHECK-NEXT: ret
- %sub = sub i64 %a, %b
- %cond = tail call i64 @llvm.umin.i64(i64 %a, i64 %sub)
- ret i64 %cond
-}
-
-; Positive test : multi-use is OK since the sub instruction still runs once
-define i64 @underflow_compare_fold_i64_multi_use(i64 %a, i64 %b, ptr addrspace(1) %ptr) {
-; CHECK-LABEL: underflow_compare_fold_i64_multi_use
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: subs x8, x0, x1
-; CHECK-NEXT: csel x0, x0, x8, lo
-; CHECK-NEXT: str x8, [x2]
-; CHECK-NEXT: ret
- %sub = sub i64 %a, %b
- store i64 %sub, ptr addrspace(1) %ptr
- %cond = call i64 @llvm.umin.i64(i64 %sub, i64 %a)
- ret i64 %cond
-}
-
-; Positive test : i32
-define i32 @underflow_compare_fold_i32(i32 %a, i32 %b) {
-; CHECK-LABEL: underflow_compare_fold_i32
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: subs w8, w0, w1
-; CHECK-NEXT: csel w0, w0, w8, lo
-; CHECK-NEXT: ret
- %sub = sub i32 %a, %b
- %cond = tail call i32 @llvm.umin.i32(i32 %sub, i32 %a)
- ret i32 %cond
-}
-
-; Positive test : i32
-define i32 @underflow_compare_fold_i32_commute(i32 %a, i32 %b) {
-; CHECK-LABEL: underflow_compare_fold_i32_commute
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: subs w8, w0, w1
-; CHECK-NEXT: csel w0, w0, w8, lo
-; CHECK-NEXT: ret
- %sub = sub i32 %a, %b
- %cond = tail call i32 @llvm.umin.i32(i32 %a, i32 %sub)
- ret i32 %cond
-}
-
-; Positive test : i32
-define i32 @underflow_compare_fold_i32_multi_use(i32 %a, i32 %b, ptr addrspace(1) %ptr) {
-; CHECK-LABEL: underflow_compare_fold_i32_multi_use
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: subs w8, w0, w1
-; CHECK-NEXT: csel w0, w0, w8, lo
-; CHECK-NEXT: str w8, [x2]
-; CHECK-NEXT: ret
- %sub = sub i32 %a, %b
- store i32 %sub, ptr addrspace(1) %ptr
- %cond = call i32 @llvm.umin.i32(i32 %sub, i32 %a)
- ret i32 %cond
-}
-
-; Negative test : i16
-define i16 @underflow_compare_fold_i16(i16 %a, i16 %b) {
-; CHECK-LABEL: underflow_compare_fold_i16
-; CHECK-LABEL: %bb.0:
-; CHECK-LABEL: sub w8, w0, w1
-; CHECK-LABEL: and w9, w0, #0xffff
-; CHECK-LABEL: and w8, w8, #0xffff
-; CHECK-LABEL: cmp w8, w9
-; CHECK-LABEL: csel w0, w8, w9, lo
-; CHECK-LABEL: ret
- %sub = sub i16 %a, %b
- %cond = tail call i16 @llvm.umin.i16(i16 %sub, i16 %a)
- ret i16 %cond
-}
-
-; Negative test : i16
-define i16 @underflow_compare_fold_i16_commute(i16 %a, i16 %b) {
-; CHECK-LABEL: underflow_compare_fold_i16_commute
-; CHECK-LABEL: %bb.0:
-; CHECK-LABEL: sub w8, w0, w1
-; CHECK-LABEL: and w9, w0, #0xffff
-; CHECK-LABEL: and w8, w8, #0xffff
-; CHECK-LABEL: cmp w9, w8
-; CHECK-LABEL: csel w0, w9, w8, lo
-; CHECK-LABEL: ret
- %sub = sub i16 %a, %b
- %cond = tail call i16 @llvm.umin.i16(i16 %a, i16 %sub)
- ret i16 %cond
-}
-
-; Negative test : i16
-define i16 @underflow_compare_fold_i16_multi_use(i16 %a, i16 %b, ptr addrspace(1) %ptr) {
-; CHECK-LABEL: underflow_compare_fold_i16_multi_use
-; CHECK-LABEL: %bb.0:
-; CHECK-LABEL: sub w8, w0, w1
-; CHECK-LABEL: and w9, w0, #0xffff
-; CHECK-LABEL: and w10, w8, #0xffff
-; CHECK-LABEL: strh w8, [x2]
-; CHECK-LABEL: cmp w10, w9
-; CHECK-LABEL: csel w0, w10, w9, lo
-; CHECK-LABEL: ret
- %sub = sub i16 %a, %b
- store i16 %sub, ptr addrspace(1) %ptr
- %cond = call i16 @llvm.umin.i16(i16 %sub, i16 %a)
- ret i16 %cond
-}
-
-; Negative test, vector types : umin(sub(a,b),a) but with vectors
-define <16 x i8> @underflow_compare_dontfold_vectors(<16 x i8> %a, <16 x i8> %b) {
-; CHECK-LABEL: underflow_compare_dontfold_vectors
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: sub v1.16b, v0.16b, v1.16b
-; CHECK-NEXT: umin v0.16b, v1.16b, v0.16b
-; CHECK-NEXT: ret
- %sub = sub <16 x i8> %a, %b
- %cond = tail call <16 x i8> @llvm.umin.v16i8(<16 x i8> %sub, <16 x i8> %a)
- ret <16 x i8> %cond
-}
-
-; Negative test, pattern mismatch : umin(add(a,b),a)
-define i64 @umin_add(i64 %a, i64 %b) {
-; CHECK-LABEL: umin_add
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: add x8, x0, x1
-; CHECK-NEXT: cmp x8, x0
-; CHECK-NEXT: csel x0, x8, x0, lo
-; CHECK-NEXT: ret
- %add = add i64 %a, %b
- %cond = tail call i64 @llvm.umin.i64(i64 %add, i64 %a)
- ret i64 %cond
-}
diff --git a/llvm/test/CodeGen/X86/umin-sub-to-usubo-select-combine.ll b/llvm/test/CodeGen/X86/umin-sub-to-usubo-select-combine.ll
deleted file mode 100644
index e9756b411eb2c..0000000000000
--- a/llvm/test/CodeGen/X86/umin-sub-to-usubo-select-combine.ll
+++ /dev/null
@@ -1,156 +0,0 @@
-; RUN: llc < %s -mtriple=x86_64 | FileCheck %s
-
-; GitHub issue #161036
-
-; Positive test : umin(sub(a,b),a) with scalar types should be folded
-define i64 @underflow_compare_fold_i64(i64 %a, i64 %b) {
-; CHECK-LABEL: underflow_compare_fold_i64
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: movq %rdi, %rax
-; CHECK-NEXT: subq %rsi, %rax
-; CHECK-NEXT: cmovbq %rdi, %rax
-; CHECK-NEXT: retq
- %sub = sub i64 %a, %b
- %cond = tail call i64 @llvm.umin.i64(i64 %sub, i64 %a)
- ret i64 %cond
-}
-
-; Positive test : umin(a,sub(a,b)) with scalar types should be folded
-define i64 @underflow_compare_fold_i64_commute(i64 %a, i64 %b) {
-; CHECK-LABEL: underflow_compare_fold_i64_commute
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: movq %rdi, %rax
-; CHECK-NEXT: subq %rsi, %rax
-; CHECK-NEXT: cmovbq %rdi, %rax
-; CHECK-NEXT: retq
- %sub = sub i64 %a, %b
- %cond = tail call i64 @llvm.umin.i64(i64 %a, i64 %sub)
- ret i64 %cond
-}
-
-; Positive test : multi-use is OK since the sub instruction still runs once
-define i64 @underflow_compare_fold_i64_multi_use(i64 %a, i64 %b, ptr addrspace(1) %ptr) {
-; CHECK-LABEL: underflow_compare_fold_i64_multi_use
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: movq %rdi, %rax
-; CHECK-NEXT: subq %rsi, %rax
-; CHECK-NEXT: movq %rax, (%rdx)
-; CHECK-NEXT: cmovbq %rdi, %rax
-; CHECK-NEXT: retq
- %sub = sub i64 %a, %b
- store i64 %sub, ptr addrspace(1) %ptr
- %cond = call i64 @llvm.umin.i64(i64 %sub, i64 %a)
- ret i64 %cond
-}
-
-; Positive test : i32
-define i32 @underflow_compare_fold_i32(i32 %a, i32 %b) {
-; CHECK-LABEL: underflow_compare_fold_i32
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: movl %edi, %eax
-; CHECK-NEXT: subl %esi, %eax
-; CHECK-NEXT: cmovbl %edi, %eax
-; CHECK-NEXT: retq
- %sub = sub i32 %a, %b
- %cond = tail call i32 @llvm.umin.i32(i32 %sub, i32 %a)
- ret i32 %cond
-}
-
-; Positive test : i32
-define i32 @underflow_compare_fold_i32_commute(i32 %a, i32 %b) {
-; CHECK-LABEL: underflow_compare_fold_i32_commute
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: movl %edi, %eax
-; CHECK-NEXT: subl %esi, %eax
-; CHECK-NEXT: cmovbl %edi, %eax
-; CHECK-NEXT: retq
- %sub = sub i32 %a, %b
- %cond = tail call i32 @llvm.umin.i32(i32 %a, i32 %sub)
- ret i32 %cond
-}
-
-; Positive test : i32
-define i32 @underflow_compare_fold_i32_multi_use(i32 %a, i32 %b, ptr addrspace(1) %ptr) {
-; CHECK-LABEL: underflow_compare_fold_i32_multi_use
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: movl %edi, %eax
-; CHECK-NEXT: subl %esi, %eax
-; CHECK-NEXT: movl %eax, (%rdx)
-; CHECK-NEXT: cmovbl %edi, %eax
-; CHECK-NEXT: retq
- %sub = sub i32 %a, %b
- store i32 %sub, ptr addrspace(1) %ptr
- %cond = call i32 @llvm.umin.i32(i32 %sub, i32 %a)
- ret i32 %cond
-}
-
-; Positive test : i16
-define i16 @underflow_compare_fold_i16(i16 %a, i16 %b) {
-; CHECK-LABEL: underflow_compare_fold_i16
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: movl %edi, %eax
-; CHECK-NEXT: subw %si, %ax
-; CHECK-NEXT: cmovbl %edi, %eax
-; CHECK-NEXT: # kill: def $ax killed $ax killed $eax
-; CHECK-NEXT: retq
- %sub = sub i16 %a, %b
- %cond = tail call i16 @llvm.umin.i16(i16 %sub, i16 %a)
- ret i16 %cond
-}
-
-; Positive test : i16
-define i16 @underflow_compare_fold_i16_commute(i16 %a, i16 %b) {
-; CHECK-LABEL: underflow_compare_fold_i16_commute
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: movl %edi, %eax
-; CHECK-NEXT: subw %si, %ax
-; CHECK-NEXT: cmovbl %edi, %eax
-; CHECK-NEXT: # kill: def $ax killed $ax killed $eax
-; CHECK-NEXT: retq
- %sub = sub i16 %a, %b
- %cond = tail call i16 @llvm.umin.i16(i16 %a, i16 %sub)
- ret i16 %cond
-}
-
-; Positive test : i16
-define i16 @underflow_compare_fold_i16_multi_use(i16 %a, i16 %b, ptr addrspace(1) %ptr) {
-; CHECK-LABEL: underflow_compare_fold_i16_multi_use
-; CHECK-LABEL: %bb.0:
-; CHECK-NEXT: movl %edi, %eax
-; CHECK-NEXT: subw %si, %ax
-; CHECK-NEXT: movw %ax, (%rdx)
-; CHECK-NEXT: cmovbl %edi, %eax
-; CHECK-NEXT: # kill: def $ax killed $ax killed $eax
-; CHECK-NEXT: retq
- %sub = sub i16 %a, %b
- store i16 %sub, ptr addrspace(1) %ptr
- %cond = call i16 @llvm.umin.i16(i16 %sub, i16 %a)
- ret i16 %cond
-}
-
-
-; Negative test, vector types : umin(sub(a,b),a) but with vectors
-define <16 x i8> @underflow_compare_dontfold_vectors(<16 x i8> %a, <16 x i8> %b) {
-; CHECK-LABEL: underflow_compare_dontfold_vectors
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: movdqa %xmm0, %xmm2
-; CHECK-NEXT: psubb %xmm1, %xmm2
-; CHECK-NEXT: pminub %xmm2, %xmm0
-; CHECK-NEXT: retq
- %sub = sub <16 x i8> %a, %b
- %cond = tail call <16 x i8> @llvm.umin.v16i8(<16 x i8> %sub, <16 x i8> %a)
- ret <16 x i8> %cond
-}
-
-; Negative test, pattern mismatch : umin(add(a,b),a)
-define i64 @umin_add(i64 %a, i64 %b) {
-; CHECK-LABEL: umin_add
-; CHECK-LABEL: %bb.0
-; CHECK-NEXT: leaq (%rsi,%rdi), %rax
-; CHECK-NEXT: cmpq %rdi, %rax
-; CHECK-NEXT: cmovaeq %rdi, %rax
-; CHECK-NEXT: retq
- %add = add i64 %a, %b
- %cond = tail call i64 @llvm.umin.i64(i64 %add, i64 %a)
- ret i64 %cond
-}
|
Member
|
Thanks for the revert, I was just about to create a PR. Do we usually reopen the issue as well? |
Member
|
Sorry my bad, I see it's already reopened. |
RKSimon
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Baseline tests from llvm#161651 that were reverted in llvm#167854 Still missing test coverage for the ffmpeg regression failures
RKSimon
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Baseline tests from llvm#161651 that were reverted in llvm#167854 Still missing test coverage for the ffmpeg regression failures
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Reverts #161651 due to downstream bad codegen reports