[llvm] [WIP][SIFoldOperands] Folding immediate into a copy invalidates candidates in the fold list (PR #148187)
Juan Manuel Martinez Caamaño via llvm-commits
llvm-commits at lists.llvm.org
Fri Jul 11 03:37:02 PDT 2025
https://github.com/jmmartinez updated https://github.com/llvm/llvm-project/pull/148187
>From 063b053f1db7b7e815d9360ee467e97a5e66cece Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Juan=20Manuel=20Martinez=20Caama=C3=B1o?= <juamarti at amd.com>
Date: Fri, 11 Jul 2025 12:30:59 +0200
Subject: [PATCH 1/4] Revert "AMDGPU: Try constant fold after folding immediate
(#141862)"
This reverts commit 80064b6e326d0cf34bac1d09c12fc1e6abecb7af.
The patch triggers a crash when the folded use can have 2 operands in
the fold list.
See https://github.com/llvm/llvm-project/pull/148187 for more info.
SWDEV-542372
---
llvm/lib/Target/AMDGPU/SIFoldOperands.cpp | 6 -----
.../AMDGPU/bit-op-reduce-width-known-bits.ll | 3 ++-
.../AMDGPU/constant-fold-imm-immreg.mir | 22 -------------------
llvm/test/CodeGen/AMDGPU/fold-imm-copy.mir | 3 ++-
.../fold-zero-high-bits-skips-non-reg.mir | 4 ++--
llvm/test/CodeGen/AMDGPU/sdiv64.ll | 7 +++---
llvm/test/CodeGen/AMDGPU/srem64.ll | 7 +++---
llvm/test/CodeGen/AMDGPU/udiv64.ll | 3 ++-
llvm/test/CodeGen/AMDGPU/urem64.ll | 7 +++---
9 files changed, 20 insertions(+), 42 deletions(-)
diff --git a/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp b/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp
index 0ed06c37507af..b8fecc382c64a 100644
--- a/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp
+++ b/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp
@@ -1782,12 +1782,6 @@ bool SIFoldOperandsImpl::foldInstOperand(MachineInstr &MI,
LLVM_DEBUG(dbgs() << "Folded source from " << MI << " into OpNo "
<< static_cast<int>(Fold.UseOpNo) << " of "
<< *Fold.UseMI);
-
- if (Fold.isImm() && tryConstantFoldOp(Fold.UseMI)) {
- LLVM_DEBUG(dbgs() << "Constant folded " << *Fold.UseMI);
- Changed = true;
- }
-
} else if (Fold.Commuted) {
// Restoring instruction's original operand order if fold has failed.
TII->commuteInstruction(*Fold.UseMI, false);
diff --git a/llvm/test/CodeGen/AMDGPU/bit-op-reduce-width-known-bits.ll b/llvm/test/CodeGen/AMDGPU/bit-op-reduce-width-known-bits.ll
index ad26dfa7f93e8..ac5f9b6b483eb 100644
--- a/llvm/test/CodeGen/AMDGPU/bit-op-reduce-width-known-bits.ll
+++ b/llvm/test/CodeGen/AMDGPU/bit-op-reduce-width-known-bits.ll
@@ -105,8 +105,9 @@ define i64 @v_xor_i64_known_i32_from_range_use_out_of_block(i64 %x) {
; CHECK-NEXT: s_and_saveexec_b64 s[4:5], vcc
; CHECK-NEXT: ; %bb.1: ; %inc
; CHECK-NEXT: v_not_b32_e32 v2, v4
+; CHECK-NEXT: v_not_b32_e32 v3, 0
; CHECK-NEXT: v_add_co_u32_e32 v2, vcc, v0, v2
-; CHECK-NEXT: v_addc_co_u32_e32 v3, vcc, -1, v1, vcc
+; CHECK-NEXT: v_addc_co_u32_e32 v3, vcc, v1, v3, vcc
; CHECK-NEXT: ; %bb.2: ; %UnifiedReturnBlock
; CHECK-NEXT: s_or_b64 exec, exec, s[4:5]
; CHECK-NEXT: v_mov_b32_e32 v0, v2
diff --git a/llvm/test/CodeGen/AMDGPU/constant-fold-imm-immreg.mir b/llvm/test/CodeGen/AMDGPU/constant-fold-imm-immreg.mir
index e7177a5e7160e..fe2b0bb1ff6ae 100644
--- a/llvm/test/CodeGen/AMDGPU/constant-fold-imm-immreg.mir
+++ b/llvm/test/CodeGen/AMDGPU/constant-fold-imm-immreg.mir
@@ -961,25 +961,3 @@ body: |
S_ENDPGM 0, implicit %2, implicit %3
...
-
----
-name: constant_v_or_b32_uses_subreg_or_0_regression
-tracksRegLiveness: true
-body: |
- bb.0:
- liveins: $vgpr0, $vgpr1
-
- ; GCN-LABEL: name: constant_v_or_b32_uses_subreg_or_0_regression
- ; GCN: liveins: $vgpr0, $vgpr1
- ; GCN-NEXT: {{ $}}
- ; GCN-NEXT: [[COPY:%[0-9]+]]:vgpr_32 = COPY $vgpr1
- ; GCN-NEXT: [[COPY1:%[0-9]+]]:vgpr_32 = COPY [[COPY]]
- ; GCN-NEXT: S_ENDPGM 0, implicit [[COPY1]]
- %0:vgpr_32 = COPY $vgpr0
- %1:vgpr_32 = COPY $vgpr1
- %2:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
- %3:vreg_64 = REG_SEQUENCE %2:vgpr_32, %subreg.sub0, %0:vgpr_32, %subreg.sub1
- %4:vgpr_32 = V_OR_B32_e64 %3.sub0:vreg_64, %1, implicit $exec
- S_ENDPGM 0, implicit %4
-
-...
diff --git a/llvm/test/CodeGen/AMDGPU/fold-imm-copy.mir b/llvm/test/CodeGen/AMDGPU/fold-imm-copy.mir
index 74c4a2da50221..d00fd9b967f37 100644
--- a/llvm/test/CodeGen/AMDGPU/fold-imm-copy.mir
+++ b/llvm/test/CodeGen/AMDGPU/fold-imm-copy.mir
@@ -43,7 +43,8 @@ body: |
; GCN-NEXT: [[DEF2:%[0-9]+]]:vgpr_32 = IMPLICIT_DEF
; GCN-NEXT: [[V_MOV_B32_e32_:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
; GCN-NEXT: [[REG_SEQUENCE:%[0-9]+]]:vreg_64 = REG_SEQUENCE killed [[DEF]], %subreg.sub0, killed [[V_MOV_B32_e32_]], %subreg.sub1
- ; GCN-NEXT: [[V_XOR_B32_e32_:%[0-9]+]]:vgpr_32 = V_XOR_B32_e32 [[DEF2]], [[REG_SEQUENCE]].sub0, implicit $exec
+ ; GCN-NEXT: [[V_XOR_B32_e32_:%[0-9]+]]:vgpr_32 = V_XOR_B32_e32 0, [[DEF1]], implicit $exec
+ ; GCN-NEXT: [[V_XOR_B32_e32_1:%[0-9]+]]:vgpr_32 = V_XOR_B32_e32 [[DEF2]], [[REG_SEQUENCE]].sub0, implicit $exec
%0:vgpr_32 = IMPLICIT_DEF
%1:vgpr_32 = IMPLICIT_DEF
%2:vgpr_32 = IMPLICIT_DEF
diff --git a/llvm/test/CodeGen/AMDGPU/fold-zero-high-bits-skips-non-reg.mir b/llvm/test/CodeGen/AMDGPU/fold-zero-high-bits-skips-non-reg.mir
index dc03eb74cbf11..b1aa88969c5bb 100644
--- a/llvm/test/CodeGen/AMDGPU/fold-zero-high-bits-skips-non-reg.mir
+++ b/llvm/test/CodeGen/AMDGPU/fold-zero-high-bits-skips-non-reg.mir
@@ -8,8 +8,8 @@ body: |
; CHECK-LABEL: name: test_tryFoldZeroHighBits_skips_nonreg
; CHECK: [[V_MOV_B32_e32_:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
; CHECK-NEXT: [[REG_SEQUENCE:%[0-9]+]]:vreg_64 = REG_SEQUENCE [[V_MOV_B32_e32_]], %subreg.sub0, [[V_MOV_B32_e32_]], %subreg.sub1
- ; CHECK-NEXT: [[V_MOV_B32_e32_1:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
- ; CHECK-NEXT: S_NOP 0, implicit [[V_MOV_B32_e32_1]]
+ ; CHECK-NEXT: [[V_AND_B32_e64_:%[0-9]+]]:vgpr_32 = V_AND_B32_e64 65535, 0, implicit $exec
+ ; CHECK-NEXT: S_NOP 0, implicit [[V_AND_B32_e64_]]
%0:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
%1:vreg_64 = REG_SEQUENCE %0, %subreg.sub0, %0, %subreg.sub1
%2:vgpr_32 = V_AND_B32_e64 65535, %1.sub0, implicit $exec
diff --git a/llvm/test/CodeGen/AMDGPU/sdiv64.ll b/llvm/test/CodeGen/AMDGPU/sdiv64.ll
index df496258a2509..15eb41a1a5b65 100644
--- a/llvm/test/CodeGen/AMDGPU/sdiv64.ll
+++ b/llvm/test/CodeGen/AMDGPU/sdiv64.ll
@@ -404,11 +404,12 @@ define i64 @v_test_sdiv(i64 %x, i64 %y) {
; GCN-IR-NEXT: ; %bb.2: ; %udiv-preheader
; GCN-IR-NEXT: v_add_i32_e32 v16, vcc, -1, v0
; GCN-IR-NEXT: v_addc_u32_e32 v17, vcc, -1, v1, vcc
-; GCN-IR-NEXT: v_not_b32_e32 v4, v10
+; GCN-IR-NEXT: v_not_b32_e32 v5, v10
; GCN-IR-NEXT: v_lshr_b64 v[8:9], v[6:7], v8
-; GCN-IR-NEXT: v_add_i32_e32 v6, vcc, v4, v11
+; GCN-IR-NEXT: v_not_b32_e32 v4, 0
+; GCN-IR-NEXT: v_add_i32_e32 v6, vcc, v5, v11
; GCN-IR-NEXT: v_mov_b32_e32 v10, 0
-; GCN-IR-NEXT: v_addc_u32_e64 v7, s[4:5], -1, 0, vcc
+; GCN-IR-NEXT: v_addc_u32_e32 v7, vcc, 0, v4, vcc
; GCN-IR-NEXT: s_mov_b64 s[10:11], 0
; GCN-IR-NEXT: v_mov_b32_e32 v11, 0
; GCN-IR-NEXT: v_mov_b32_e32 v5, 0
diff --git a/llvm/test/CodeGen/AMDGPU/srem64.ll b/llvm/test/CodeGen/AMDGPU/srem64.ll
index 47dfa9f4fc2d3..c729c3fb8a4e4 100644
--- a/llvm/test/CodeGen/AMDGPU/srem64.ll
+++ b/llvm/test/CodeGen/AMDGPU/srem64.ll
@@ -380,11 +380,12 @@ define i64 @v_test_srem(i64 %x, i64 %y) {
; GCN-IR-NEXT: ; %bb.2: ; %udiv-preheader
; GCN-IR-NEXT: v_add_i32_e32 v16, vcc, -1, v2
; GCN-IR-NEXT: v_addc_u32_e32 v17, vcc, -1, v3, vcc
-; GCN-IR-NEXT: v_not_b32_e32 v6, v12
+; GCN-IR-NEXT: v_not_b32_e32 v7, v12
; GCN-IR-NEXT: v_lshr_b64 v[10:11], v[0:1], v8
-; GCN-IR-NEXT: v_add_i32_e32 v8, vcc, v6, v13
+; GCN-IR-NEXT: v_not_b32_e32 v6, 0
+; GCN-IR-NEXT: v_add_i32_e32 v8, vcc, v7, v13
; GCN-IR-NEXT: v_mov_b32_e32 v12, 0
-; GCN-IR-NEXT: v_addc_u32_e64 v9, s[4:5], -1, 0, vcc
+; GCN-IR-NEXT: v_addc_u32_e32 v9, vcc, 0, v6, vcc
; GCN-IR-NEXT: s_mov_b64 s[10:11], 0
; GCN-IR-NEXT: v_mov_b32_e32 v13, 0
; GCN-IR-NEXT: v_mov_b32_e32 v7, 0
diff --git a/llvm/test/CodeGen/AMDGPU/udiv64.ll b/llvm/test/CodeGen/AMDGPU/udiv64.ll
index e9017939f8a4a..5acbb044c1057 100644
--- a/llvm/test/CodeGen/AMDGPU/udiv64.ll
+++ b/llvm/test/CodeGen/AMDGPU/udiv64.ll
@@ -348,9 +348,10 @@ define i64 @v_test_udiv_i64(i64 %x, i64 %y) {
; GCN-IR-NEXT: v_lshr_b64 v[8:9], v[0:1], v10
; GCN-IR-NEXT: v_addc_u32_e32 v13, vcc, -1, v3, vcc
; GCN-IR-NEXT: v_not_b32_e32 v0, v14
+; GCN-IR-NEXT: v_not_b32_e32 v1, 0
; GCN-IR-NEXT: v_add_i32_e32 v0, vcc, v0, v15
; GCN-IR-NEXT: v_mov_b32_e32 v10, 0
-; GCN-IR-NEXT: v_addc_u32_e64 v1, s[4:5], -1, 0, vcc
+; GCN-IR-NEXT: v_addc_u32_e32 v1, vcc, 0, v1, vcc
; GCN-IR-NEXT: s_mov_b64 s[10:11], 0
; GCN-IR-NEXT: v_mov_b32_e32 v11, 0
; GCN-IR-NEXT: v_mov_b32_e32 v7, 0
diff --git a/llvm/test/CodeGen/AMDGPU/urem64.ll b/llvm/test/CodeGen/AMDGPU/urem64.ll
index 6480a88d40f5a..94f1b83ea2765 100644
--- a/llvm/test/CodeGen/AMDGPU/urem64.ll
+++ b/llvm/test/CodeGen/AMDGPU/urem64.ll
@@ -355,11 +355,12 @@ define i64 @v_test_urem_i64(i64 %x, i64 %y) {
; GCN-IR-NEXT: ; %bb.2: ; %udiv-preheader
; GCN-IR-NEXT: v_add_i32_e32 v14, vcc, -1, v2
; GCN-IR-NEXT: v_addc_u32_e32 v15, vcc, -1, v3, vcc
-; GCN-IR-NEXT: v_not_b32_e32 v6, v12
+; GCN-IR-NEXT: v_not_b32_e32 v7, v12
; GCN-IR-NEXT: v_lshr_b64 v[10:11], v[0:1], v8
-; GCN-IR-NEXT: v_add_i32_e32 v8, vcc, v6, v13
+; GCN-IR-NEXT: v_not_b32_e32 v6, 0
+; GCN-IR-NEXT: v_add_i32_e32 v8, vcc, v7, v13
; GCN-IR-NEXT: v_mov_b32_e32 v12, 0
-; GCN-IR-NEXT: v_addc_u32_e64 v9, s[4:5], -1, 0, vcc
+; GCN-IR-NEXT: v_addc_u32_e32 v9, vcc, 0, v6, vcc
; GCN-IR-NEXT: s_mov_b64 s[10:11], 0
; GCN-IR-NEXT: v_mov_b32_e32 v13, 0
; GCN-IR-NEXT: v_mov_b32_e32 v7, 0
>From 43b97d34a1df7eed6d703f0528ceca463664e075 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Juan=20Manuel=20Martinez=20Caama=C3=B1o?= <juamarti at amd.com>
Date: Fri, 11 Jul 2025 12:35:54 +0200
Subject: [PATCH 2/4] Reapply "AMDGPU: Try constant fold after folding
immediate (#141862)"
This reverts commit 063b053f1db7b7e815d9360ee467e97a5e66cece.
---
llvm/lib/Target/AMDGPU/SIFoldOperands.cpp | 6 +++++
.../AMDGPU/bit-op-reduce-width-known-bits.ll | 3 +--
.../AMDGPU/constant-fold-imm-immreg.mir | 22 +++++++++++++++++++
llvm/test/CodeGen/AMDGPU/fold-imm-copy.mir | 3 +--
.../fold-zero-high-bits-skips-non-reg.mir | 4 ++--
llvm/test/CodeGen/AMDGPU/sdiv64.ll | 7 +++---
llvm/test/CodeGen/AMDGPU/srem64.ll | 7 +++---
llvm/test/CodeGen/AMDGPU/udiv64.ll | 3 +--
llvm/test/CodeGen/AMDGPU/urem64.ll | 7 +++---
9 files changed, 42 insertions(+), 20 deletions(-)
diff --git a/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp b/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp
index b8fecc382c64a..0ed06c37507af 100644
--- a/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp
+++ b/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp
@@ -1782,6 +1782,12 @@ bool SIFoldOperandsImpl::foldInstOperand(MachineInstr &MI,
LLVM_DEBUG(dbgs() << "Folded source from " << MI << " into OpNo "
<< static_cast<int>(Fold.UseOpNo) << " of "
<< *Fold.UseMI);
+
+ if (Fold.isImm() && tryConstantFoldOp(Fold.UseMI)) {
+ LLVM_DEBUG(dbgs() << "Constant folded " << *Fold.UseMI);
+ Changed = true;
+ }
+
} else if (Fold.Commuted) {
// Restoring instruction's original operand order if fold has failed.
TII->commuteInstruction(*Fold.UseMI, false);
diff --git a/llvm/test/CodeGen/AMDGPU/bit-op-reduce-width-known-bits.ll b/llvm/test/CodeGen/AMDGPU/bit-op-reduce-width-known-bits.ll
index ac5f9b6b483eb..ad26dfa7f93e8 100644
--- a/llvm/test/CodeGen/AMDGPU/bit-op-reduce-width-known-bits.ll
+++ b/llvm/test/CodeGen/AMDGPU/bit-op-reduce-width-known-bits.ll
@@ -105,9 +105,8 @@ define i64 @v_xor_i64_known_i32_from_range_use_out_of_block(i64 %x) {
; CHECK-NEXT: s_and_saveexec_b64 s[4:5], vcc
; CHECK-NEXT: ; %bb.1: ; %inc
; CHECK-NEXT: v_not_b32_e32 v2, v4
-; CHECK-NEXT: v_not_b32_e32 v3, 0
; CHECK-NEXT: v_add_co_u32_e32 v2, vcc, v0, v2
-; CHECK-NEXT: v_addc_co_u32_e32 v3, vcc, v1, v3, vcc
+; CHECK-NEXT: v_addc_co_u32_e32 v3, vcc, -1, v1, vcc
; CHECK-NEXT: ; %bb.2: ; %UnifiedReturnBlock
; CHECK-NEXT: s_or_b64 exec, exec, s[4:5]
; CHECK-NEXT: v_mov_b32_e32 v0, v2
diff --git a/llvm/test/CodeGen/AMDGPU/constant-fold-imm-immreg.mir b/llvm/test/CodeGen/AMDGPU/constant-fold-imm-immreg.mir
index fe2b0bb1ff6ae..e7177a5e7160e 100644
--- a/llvm/test/CodeGen/AMDGPU/constant-fold-imm-immreg.mir
+++ b/llvm/test/CodeGen/AMDGPU/constant-fold-imm-immreg.mir
@@ -961,3 +961,25 @@ body: |
S_ENDPGM 0, implicit %2, implicit %3
...
+
+---
+name: constant_v_or_b32_uses_subreg_or_0_regression
+tracksRegLiveness: true
+body: |
+ bb.0:
+ liveins: $vgpr0, $vgpr1
+
+ ; GCN-LABEL: name: constant_v_or_b32_uses_subreg_or_0_regression
+ ; GCN: liveins: $vgpr0, $vgpr1
+ ; GCN-NEXT: {{ $}}
+ ; GCN-NEXT: [[COPY:%[0-9]+]]:vgpr_32 = COPY $vgpr1
+ ; GCN-NEXT: [[COPY1:%[0-9]+]]:vgpr_32 = COPY [[COPY]]
+ ; GCN-NEXT: S_ENDPGM 0, implicit [[COPY1]]
+ %0:vgpr_32 = COPY $vgpr0
+ %1:vgpr_32 = COPY $vgpr1
+ %2:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
+ %3:vreg_64 = REG_SEQUENCE %2:vgpr_32, %subreg.sub0, %0:vgpr_32, %subreg.sub1
+ %4:vgpr_32 = V_OR_B32_e64 %3.sub0:vreg_64, %1, implicit $exec
+ S_ENDPGM 0, implicit %4
+
+...
diff --git a/llvm/test/CodeGen/AMDGPU/fold-imm-copy.mir b/llvm/test/CodeGen/AMDGPU/fold-imm-copy.mir
index d00fd9b967f37..74c4a2da50221 100644
--- a/llvm/test/CodeGen/AMDGPU/fold-imm-copy.mir
+++ b/llvm/test/CodeGen/AMDGPU/fold-imm-copy.mir
@@ -43,8 +43,7 @@ body: |
; GCN-NEXT: [[DEF2:%[0-9]+]]:vgpr_32 = IMPLICIT_DEF
; GCN-NEXT: [[V_MOV_B32_e32_:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
; GCN-NEXT: [[REG_SEQUENCE:%[0-9]+]]:vreg_64 = REG_SEQUENCE killed [[DEF]], %subreg.sub0, killed [[V_MOV_B32_e32_]], %subreg.sub1
- ; GCN-NEXT: [[V_XOR_B32_e32_:%[0-9]+]]:vgpr_32 = V_XOR_B32_e32 0, [[DEF1]], implicit $exec
- ; GCN-NEXT: [[V_XOR_B32_e32_1:%[0-9]+]]:vgpr_32 = V_XOR_B32_e32 [[DEF2]], [[REG_SEQUENCE]].sub0, implicit $exec
+ ; GCN-NEXT: [[V_XOR_B32_e32_:%[0-9]+]]:vgpr_32 = V_XOR_B32_e32 [[DEF2]], [[REG_SEQUENCE]].sub0, implicit $exec
%0:vgpr_32 = IMPLICIT_DEF
%1:vgpr_32 = IMPLICIT_DEF
%2:vgpr_32 = IMPLICIT_DEF
diff --git a/llvm/test/CodeGen/AMDGPU/fold-zero-high-bits-skips-non-reg.mir b/llvm/test/CodeGen/AMDGPU/fold-zero-high-bits-skips-non-reg.mir
index b1aa88969c5bb..dc03eb74cbf11 100644
--- a/llvm/test/CodeGen/AMDGPU/fold-zero-high-bits-skips-non-reg.mir
+++ b/llvm/test/CodeGen/AMDGPU/fold-zero-high-bits-skips-non-reg.mir
@@ -8,8 +8,8 @@ body: |
; CHECK-LABEL: name: test_tryFoldZeroHighBits_skips_nonreg
; CHECK: [[V_MOV_B32_e32_:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
; CHECK-NEXT: [[REG_SEQUENCE:%[0-9]+]]:vreg_64 = REG_SEQUENCE [[V_MOV_B32_e32_]], %subreg.sub0, [[V_MOV_B32_e32_]], %subreg.sub1
- ; CHECK-NEXT: [[V_AND_B32_e64_:%[0-9]+]]:vgpr_32 = V_AND_B32_e64 65535, 0, implicit $exec
- ; CHECK-NEXT: S_NOP 0, implicit [[V_AND_B32_e64_]]
+ ; CHECK-NEXT: [[V_MOV_B32_e32_1:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
+ ; CHECK-NEXT: S_NOP 0, implicit [[V_MOV_B32_e32_1]]
%0:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
%1:vreg_64 = REG_SEQUENCE %0, %subreg.sub0, %0, %subreg.sub1
%2:vgpr_32 = V_AND_B32_e64 65535, %1.sub0, implicit $exec
diff --git a/llvm/test/CodeGen/AMDGPU/sdiv64.ll b/llvm/test/CodeGen/AMDGPU/sdiv64.ll
index 15eb41a1a5b65..df496258a2509 100644
--- a/llvm/test/CodeGen/AMDGPU/sdiv64.ll
+++ b/llvm/test/CodeGen/AMDGPU/sdiv64.ll
@@ -404,12 +404,11 @@ define i64 @v_test_sdiv(i64 %x, i64 %y) {
; GCN-IR-NEXT: ; %bb.2: ; %udiv-preheader
; GCN-IR-NEXT: v_add_i32_e32 v16, vcc, -1, v0
; GCN-IR-NEXT: v_addc_u32_e32 v17, vcc, -1, v1, vcc
-; GCN-IR-NEXT: v_not_b32_e32 v5, v10
+; GCN-IR-NEXT: v_not_b32_e32 v4, v10
; GCN-IR-NEXT: v_lshr_b64 v[8:9], v[6:7], v8
-; GCN-IR-NEXT: v_not_b32_e32 v4, 0
-; GCN-IR-NEXT: v_add_i32_e32 v6, vcc, v5, v11
+; GCN-IR-NEXT: v_add_i32_e32 v6, vcc, v4, v11
; GCN-IR-NEXT: v_mov_b32_e32 v10, 0
-; GCN-IR-NEXT: v_addc_u32_e32 v7, vcc, 0, v4, vcc
+; GCN-IR-NEXT: v_addc_u32_e64 v7, s[4:5], -1, 0, vcc
; GCN-IR-NEXT: s_mov_b64 s[10:11], 0
; GCN-IR-NEXT: v_mov_b32_e32 v11, 0
; GCN-IR-NEXT: v_mov_b32_e32 v5, 0
diff --git a/llvm/test/CodeGen/AMDGPU/srem64.ll b/llvm/test/CodeGen/AMDGPU/srem64.ll
index c729c3fb8a4e4..47dfa9f4fc2d3 100644
--- a/llvm/test/CodeGen/AMDGPU/srem64.ll
+++ b/llvm/test/CodeGen/AMDGPU/srem64.ll
@@ -380,12 +380,11 @@ define i64 @v_test_srem(i64 %x, i64 %y) {
; GCN-IR-NEXT: ; %bb.2: ; %udiv-preheader
; GCN-IR-NEXT: v_add_i32_e32 v16, vcc, -1, v2
; GCN-IR-NEXT: v_addc_u32_e32 v17, vcc, -1, v3, vcc
-; GCN-IR-NEXT: v_not_b32_e32 v7, v12
+; GCN-IR-NEXT: v_not_b32_e32 v6, v12
; GCN-IR-NEXT: v_lshr_b64 v[10:11], v[0:1], v8
-; GCN-IR-NEXT: v_not_b32_e32 v6, 0
-; GCN-IR-NEXT: v_add_i32_e32 v8, vcc, v7, v13
+; GCN-IR-NEXT: v_add_i32_e32 v8, vcc, v6, v13
; GCN-IR-NEXT: v_mov_b32_e32 v12, 0
-; GCN-IR-NEXT: v_addc_u32_e32 v9, vcc, 0, v6, vcc
+; GCN-IR-NEXT: v_addc_u32_e64 v9, s[4:5], -1, 0, vcc
; GCN-IR-NEXT: s_mov_b64 s[10:11], 0
; GCN-IR-NEXT: v_mov_b32_e32 v13, 0
; GCN-IR-NEXT: v_mov_b32_e32 v7, 0
diff --git a/llvm/test/CodeGen/AMDGPU/udiv64.ll b/llvm/test/CodeGen/AMDGPU/udiv64.ll
index 5acbb044c1057..e9017939f8a4a 100644
--- a/llvm/test/CodeGen/AMDGPU/udiv64.ll
+++ b/llvm/test/CodeGen/AMDGPU/udiv64.ll
@@ -348,10 +348,9 @@ define i64 @v_test_udiv_i64(i64 %x, i64 %y) {
; GCN-IR-NEXT: v_lshr_b64 v[8:9], v[0:1], v10
; GCN-IR-NEXT: v_addc_u32_e32 v13, vcc, -1, v3, vcc
; GCN-IR-NEXT: v_not_b32_e32 v0, v14
-; GCN-IR-NEXT: v_not_b32_e32 v1, 0
; GCN-IR-NEXT: v_add_i32_e32 v0, vcc, v0, v15
; GCN-IR-NEXT: v_mov_b32_e32 v10, 0
-; GCN-IR-NEXT: v_addc_u32_e32 v1, vcc, 0, v1, vcc
+; GCN-IR-NEXT: v_addc_u32_e64 v1, s[4:5], -1, 0, vcc
; GCN-IR-NEXT: s_mov_b64 s[10:11], 0
; GCN-IR-NEXT: v_mov_b32_e32 v11, 0
; GCN-IR-NEXT: v_mov_b32_e32 v7, 0
diff --git a/llvm/test/CodeGen/AMDGPU/urem64.ll b/llvm/test/CodeGen/AMDGPU/urem64.ll
index 94f1b83ea2765..6480a88d40f5a 100644
--- a/llvm/test/CodeGen/AMDGPU/urem64.ll
+++ b/llvm/test/CodeGen/AMDGPU/urem64.ll
@@ -355,12 +355,11 @@ define i64 @v_test_urem_i64(i64 %x, i64 %y) {
; GCN-IR-NEXT: ; %bb.2: ; %udiv-preheader
; GCN-IR-NEXT: v_add_i32_e32 v14, vcc, -1, v2
; GCN-IR-NEXT: v_addc_u32_e32 v15, vcc, -1, v3, vcc
-; GCN-IR-NEXT: v_not_b32_e32 v7, v12
+; GCN-IR-NEXT: v_not_b32_e32 v6, v12
; GCN-IR-NEXT: v_lshr_b64 v[10:11], v[0:1], v8
-; GCN-IR-NEXT: v_not_b32_e32 v6, 0
-; GCN-IR-NEXT: v_add_i32_e32 v8, vcc, v7, v13
+; GCN-IR-NEXT: v_add_i32_e32 v8, vcc, v6, v13
; GCN-IR-NEXT: v_mov_b32_e32 v12, 0
-; GCN-IR-NEXT: v_addc_u32_e32 v9, vcc, 0, v6, vcc
+; GCN-IR-NEXT: v_addc_u32_e64 v9, s[4:5], -1, 0, vcc
; GCN-IR-NEXT: s_mov_b64 s[10:11], 0
; GCN-IR-NEXT: v_mov_b32_e32 v13, 0
; GCN-IR-NEXT: v_mov_b32_e32 v7, 0
>From 610894bc195d8fb2ddbfa4d5f5427a2baff5948e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Juan=20Manuel=20Martinez=20Caama=C3=B1o?= <juamarti at amd.com>
Date: Fri, 11 Jul 2025 11:47:56 +0200
Subject: [PATCH 3/4] Pre-Commit test: SWDEV-542372: crash in si-fold-operands
---
.../AMDGPU/si-fold-operands-swdev-542372.ll | 37 +++++++++++++++++++
1 file changed, 37 insertions(+)
create mode 100644 llvm/test/CodeGen/AMDGPU/si-fold-operands-swdev-542372.ll
diff --git a/llvm/test/CodeGen/AMDGPU/si-fold-operands-swdev-542372.ll b/llvm/test/CodeGen/AMDGPU/si-fold-operands-swdev-542372.ll
new file mode 100644
index 0000000000000..43fe5c748b28f
--- /dev/null
+++ b/llvm/test/CodeGen/AMDGPU/si-fold-operands-swdev-542372.ll
@@ -0,0 +1,37 @@
+; RUN: not --crash llc -O3 -mtriple=amdgcn-amd-amdhsa -mcpu=gfx90a %s -o /dev/null
+
+define amdgpu_kernel void @kernel() {
+entry:
+ %0 = load <2 x i32>, ptr addrspace(3) null, align 8
+ %vecext.i55 = extractelement <2 x i32> %0, i64 0
+ %cmp3.i57 = icmp eq i32 %vecext.i55, 2
+ store i32 0, ptr addrspace(3) null, align 8
+ br i1 %cmp3.i57, label %land.rhs49, label %land.end59
+
+land.rhs49: ; preds = %entry
+ %1 = load <2 x i32>, ptr addrspace(3) null, align 8
+ %vecext.i67 = extractelement <2 x i32> %1, i64 0
+ %cmp3.i69 = icmp eq i32 %vecext.i67, 1
+ br i1 %cmp3.i69, label %land.rhs57, label %land.end59
+
+land.rhs57: ; preds = %land.rhs49
+ %rem.i.i.i = srem <2 x i32> %0, %1
+ %ref.tmp.sroa.0.0.vec.extract.i.i = extractelement <2 x i32> %rem.i.i.i, i64 0
+ store i32 %ref.tmp.sroa.0.0.vec.extract.i.i, ptr addrspace(3) null, align 8
+ store i32 %ref.tmp.sroa.0.0.vec.extract.i.i, ptr addrspace(3) getelementptr inbounds nuw (i8, ptr addrspace(3) null, i32 4), align 4
+ %2 = load <2 x i32>, ptr addrspace(3) null, align 8
+ %vecext.i.i.i = extractelement <2 x i32> %2, i64 0
+ %cmp3.i.i.i = icmp ne i32 %vecext.i.i.i, 0
+ %vecext.1.i.i.i = extractelement <2 x i32> %2, i64 1
+ %cmp3.1.i.i.i = icmp ne i32 %vecext.1.i.i.i, 0
+ %.not.i.i = select i1 %cmp3.i.i.i, i1 true, i1 %cmp3.1.i.i.i
+ br i1 %.not.i.i, label %land.end59, label %if.end.i
+
+if.end.i: ; preds = %land.rhs57
+ %and.i.i.i = and <2 x i32> %2, splat (i32 1)
+ %ref.tmp.sroa.0.0.vec.extract.i20.i = extractelement <2 x i32> %and.i.i.i, i64 0
+ br label %land.end59
+
+land.end59: ; preds = %if.end.i, %land.rhs57, %land.rhs49, %entry
+ ret void
+}
>From 062d1973120d4f4ff6feefe37647c721ef0418b4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Juan=20Manuel=20Martinez=20Caama=C3=B1o?= <juamarti at amd.com>
Date: Fri, 11 Jul 2025 11:48:37 +0200
Subject: [PATCH 4/4] [SIFoldOperands] Folding immediate into a copy
invalidates candidates in the fold list
Fixes SWDEV-542372
---
llvm/lib/Target/AMDGPU/SIFoldOperands.cpp | 10 ++++++--
.../AMDGPU/si-fold-operands-swdev-542372.ll | 25 ++++++++++++++++++-
2 files changed, 32 insertions(+), 3 deletions(-)
diff --git a/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp b/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp
index 0ed06c37507af..2675e4e9d02e4 100644
--- a/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp
+++ b/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp
@@ -1761,7 +1761,9 @@ bool SIFoldOperandsImpl::foldInstOperand(MachineInstr &MI,
for (MachineInstr *Copy : CopiesToReplace)
Copy->addImplicitDefUseOperands(*MF);
- for (FoldCandidate &Fold : FoldList) {
+ for (auto FoldIt = FoldList.begin(), End = FoldList.end(); FoldIt != End;
+ ++FoldIt) {
+ FoldCandidate &Fold = *FoldIt;
assert(!Fold.isReg() || Fold.Def.OpToFold);
if (Fold.isReg() && Fold.getReg().isVirtual()) {
Register Reg = Fold.getReg();
@@ -1785,9 +1787,13 @@ bool SIFoldOperandsImpl::foldInstOperand(MachineInstr &MI,
if (Fold.isImm() && tryConstantFoldOp(Fold.UseMI)) {
LLVM_DEBUG(dbgs() << "Constant folded " << *Fold.UseMI);
+ // The instruction was folded into a copy, we have to skip any other
+ // occurence of UseMI in the fold list
+ End = std::remove_if(FoldIt + 1, End, [&](const FoldCandidate &F) {
+ return F.UseMI == Fold.UseMI;
+ });
Changed = true;
}
-
} else if (Fold.Commuted) {
// Restoring instruction's original operand order if fold has failed.
TII->commuteInstruction(*Fold.UseMI, false);
diff --git a/llvm/test/CodeGen/AMDGPU/si-fold-operands-swdev-542372.ll b/llvm/test/CodeGen/AMDGPU/si-fold-operands-swdev-542372.ll
index 43fe5c748b28f..2b6f6ba6a4de8 100644
--- a/llvm/test/CodeGen/AMDGPU/si-fold-operands-swdev-542372.ll
+++ b/llvm/test/CodeGen/AMDGPU/si-fold-operands-swdev-542372.ll
@@ -1,6 +1,29 @@
-; RUN: not --crash llc -O3 -mtriple=amdgcn-amd-amdhsa -mcpu=gfx90a %s -o /dev/null
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -O3 -mtriple=amdgcn-amd-amdhsa -mcpu=gfx90a %s -o - | FileCheck %s
define amdgpu_kernel void @kernel() {
+; CHECK-LABEL: kernel:
+; CHECK: ; %bb.0: ; %entry
+; CHECK-NEXT: v_mov_b32_e32 v0, 0
+; CHECK-NEXT: ds_read_b64 v[2:3], v0
+; CHECK-NEXT: ds_write_b32 v0, v0
+; CHECK-NEXT: s_waitcnt lgkmcnt(1)
+; CHECK-NEXT: v_cmp_ne_u32_e32 vcc, 2, v2
+; CHECK-NEXT: s_cbranch_vccnz .LBB0_3
+; CHECK-NEXT: ; %bb.1: ; %land.rhs49
+; CHECK-NEXT: ds_read_b64 v[0:1], v0
+; CHECK-NEXT: s_waitcnt lgkmcnt(0)
+; CHECK-NEXT: v_cmp_ne_u32_e32 vcc, 1, v0
+; CHECK-NEXT: s_cbranch_vccnz .LBB0_3
+; CHECK-NEXT: ; %bb.2: ; %land.rhs57
+; CHECK-NEXT: s_mov_b32 s0, 0
+; CHECK-NEXT: s_mov_b32 s1, s0
+; CHECK-NEXT: v_mov_b32_e32 v2, 0
+; CHECK-NEXT: v_pk_mov_b32 v[0:1], s[0:1], s[0:1] op_sel:[0,1]
+; CHECK-NEXT: s_cmp_lg_u32 s0, 0
+; CHECK-NEXT: ds_write_b64 v2, v[0:1]
+; CHECK-NEXT: .LBB0_3: ; %land.end59
+; CHECK-NEXT: s_endpgm
entry:
%0 = load <2 x i32>, ptr addrspace(3) null, align 8
%vecext.i55 = extractelement <2 x i32> %0, i64 0
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