[llvm] [SystemZ] Avoid trunc(add(X,X)) patterns (PR #164378)
Simon Pilgrim via llvm-commits
llvm-commits at lists.llvm.org
Tue Oct 21 02:07:55 PDT 2025
https://github.com/RKSimon created https://github.com/llvm/llvm-project/pull/164378
Replace with trunc(add(X,Y)) to avoid premature folding in upcoming patch #164227
>From 013e2d5b6b19b3319803d0a1984eed6023abab38 Mon Sep 17 00:00:00 2001
From: Simon Pilgrim <llvm-dev at redking.me.uk>
Date: Tue, 21 Oct 2025 10:06:57 +0100
Subject: [PATCH] [SystemZ] Avoid trunc(add(X,X)) patterns
Replace with trunc(add(X,Y)) to avoid premature folding in upcoming patch #164227
---
llvm/test/CodeGen/SystemZ/int-conv-14.ll | 45 +++++++++++++-----------
llvm/test/CodeGen/SystemZ/int-conv-15.ll | 45 +++++++++++++-----------
2 files changed, 50 insertions(+), 40 deletions(-)
diff --git a/llvm/test/CodeGen/SystemZ/int-conv-14.ll b/llvm/test/CodeGen/SystemZ/int-conv-14.ll
index 98dc88f289620..baab5ac7f4b5c 100644
--- a/llvm/test/CodeGen/SystemZ/int-conv-14.ll
+++ b/llvm/test/CodeGen/SystemZ/int-conv-14.ll
@@ -55,14 +55,15 @@ define i128 @f4(ptr %ptr) {
}
; Truncation to i64.
-define i64 @f5(i128 %a) {
+define i64 @f5(i128 %a, i128 %b) {
; CHECK-LABEL: f5:
; CHECK: # %bb.0:
-; CHECK-NEXT: vl %v0, 0(%r2), 3
-; CHECK-NEXT: vaq %v0, %v0, %v0
+; CHECK-NEXT: vl %v0, 0(%r3), 3
+; CHECK-NEXT: vl %v1, 0(%r2), 3
+; CHECK-NEXT: vaq %v0, %v1, %v0
; CHECK-NEXT: vlgvg %r2, %v0, 1
; CHECK-NEXT: br %r14
- %op = add i128 %a, %a
+ %op = add i128 %a, %b
%res = trunc i128 %op to i64
ret i64 %res
}
@@ -134,15 +135,16 @@ define i128 @f10(ptr %ptr) {
}
; Truncation to i32.
-define i32 @f11(i128 %a) {
+define i32 @f11(i128 %a, i128 %b) {
; CHECK-LABEL: f11:
; CHECK: # %bb.0:
-; CHECK-NEXT: vl %v0, 0(%r2), 3
-; CHECK-NEXT: vaq %v0, %v0, %v0
+; CHECK-NEXT: vl %v0, 0(%r3), 3
+; CHECK-NEXT: vl %v1, 0(%r2), 3
+; CHECK-NEXT: vaq %v0, %v1, %v0
; CHECK-NEXT: vlgvf %r2, %v0, 3
; CHECK-NEXT: # kill: def $r2l killed $r2l killed $r2d
; CHECK-NEXT: br %r14
- %op = add i128 %a, %a
+ %op = add i128 %a, %b
%res = trunc i128 %op to i32
ret i32 %res
}
@@ -215,15 +217,16 @@ define i128 @f16(ptr %ptr) {
}
; Truncation to i16.
-define i16 @f17(i128 %a) {
+define i16 @f17(i128 %a, i128 %b) {
; CHECK-LABEL: f17:
; CHECK: # %bb.0:
-; CHECK-NEXT: vl %v0, 0(%r2), 3
-; CHECK-NEXT: vaq %v0, %v0, %v0
+; CHECK-NEXT: vl %v0, 0(%r3), 3
+; CHECK-NEXT: vl %v1, 0(%r2), 3
+; CHECK-NEXT: vaq %v0, %v1, %v0
; CHECK-NEXT: vlgvf %r2, %v0, 3
; CHECK-NEXT: # kill: def $r2l killed $r2l killed $r2d
; CHECK-NEXT: br %r14
- %op = add i128 %a, %a
+ %op = add i128 %a, %b
%res = trunc i128 %op to i16
ret i16 %res
}
@@ -296,15 +299,16 @@ define i128 @f22(ptr %ptr) {
}
; Truncation to i8.
-define i8 @f23(i128 %a) {
+define i8 @f23(i128 %a, i128 %b) {
; CHECK-LABEL: f23:
; CHECK: # %bb.0:
-; CHECK-NEXT: vl %v0, 0(%r2), 3
-; CHECK-NEXT: vaq %v0, %v0, %v0
+; CHECK-NEXT: vl %v0, 0(%r3), 3
+; CHECK-NEXT: vl %v1, 0(%r2), 3
+; CHECK-NEXT: vaq %v0, %v1, %v0
; CHECK-NEXT: vlgvf %r2, %v0, 3
; CHECK-NEXT: # kill: def $r2l killed $r2l killed $r2d
; CHECK-NEXT: br %r14
- %op = add i128 %a, %a
+ %op = add i128 %a, %b
%res = trunc i128 %op to i8
ret i8 %res
}
@@ -385,15 +389,16 @@ define i128 @f28(ptr %ptr) {
}
; Truncation to i1.
-define i1 @f29(i128 %a) {
+define i1 @f29(i128 %a, i128 %b) {
; CHECK-LABEL: f29:
; CHECK: # %bb.0:
-; CHECK-NEXT: vl %v0, 0(%r2), 3
-; CHECK-NEXT: vaq %v0, %v0, %v0
+; CHECK-NEXT: vl %v0, 0(%r3), 3
+; CHECK-NEXT: vl %v1, 0(%r2), 3
+; CHECK-NEXT: vaq %v0, %v1, %v0
; CHECK-NEXT: vlgvf %r2, %v0, 3
; CHECK-NEXT: # kill: def $r2l killed $r2l killed $r2d
; CHECK-NEXT: br %r14
- %op = add i128 %a, %a
+ %op = add i128 %a, %b
%res = trunc i128 %op to i1
ret i1 %res
}
diff --git a/llvm/test/CodeGen/SystemZ/int-conv-15.ll b/llvm/test/CodeGen/SystemZ/int-conv-15.ll
index 0d8ee75b10b85..f2c9ee5fa1f57 100644
--- a/llvm/test/CodeGen/SystemZ/int-conv-15.ll
+++ b/llvm/test/CodeGen/SystemZ/int-conv-15.ll
@@ -55,14 +55,15 @@ define i128 @f4(ptr %ptr) {
}
; Truncation to i64.
-define i64 @f5(i128 %a) {
+define i64 @f5(i128 %a, i128 %b) {
; CHECK-LABEL: f5:
; CHECK: # %bb.0:
-; CHECK-NEXT: vl %v0, 0(%r2), 3
-; CHECK-NEXT: vaq %v0, %v0, %v0
+; CHECK-NEXT: vl %v0, 0(%r3), 3
+; CHECK-NEXT: vl %v1, 0(%r2), 3
+; CHECK-NEXT: vaq %v0, %v1, %v0
; CHECK-NEXT: vlgvg %r2, %v0, 1
; CHECK-NEXT: br %r14
- %op = add i128 %a, %a
+ %op = add i128 %a, %b
%res = trunc i128 %op to i64
ret i64 %res
}
@@ -134,15 +135,16 @@ define i128 @f10(ptr %ptr) {
}
; Truncation to i32.
-define i32 @f11(i128 %a) {
+define i32 @f11(i128 %a, i128 %b) {
; CHECK-LABEL: f11:
; CHECK: # %bb.0:
-; CHECK-NEXT: vl %v0, 0(%r2), 3
-; CHECK-NEXT: vaq %v0, %v0, %v0
+; CHECK-NEXT: vl %v0, 0(%r3), 3
+; CHECK-NEXT: vl %v1, 0(%r2), 3
+; CHECK-NEXT: vaq %v0, %v1, %v0
; CHECK-NEXT: vlgvf %r2, %v0, 3
; CHECK-NEXT: # kill: def $r2l killed $r2l killed $r2d
; CHECK-NEXT: br %r14
- %op = add i128 %a, %a
+ %op = add i128 %a, %b
%res = trunc i128 %op to i32
ret i32 %res
}
@@ -215,15 +217,16 @@ define i128 @f16(ptr %ptr) {
}
; Truncation to i16.
-define i16 @f17(i128 %a) {
+define i16 @f17(i128 %a, i128 %b) {
; CHECK-LABEL: f17:
; CHECK: # %bb.0:
-; CHECK-NEXT: vl %v0, 0(%r2), 3
-; CHECK-NEXT: vaq %v0, %v0, %v0
+; CHECK-NEXT: vl %v0, 0(%r3), 3
+; CHECK-NEXT: vl %v1, 0(%r2), 3
+; CHECK-NEXT: vaq %v0, %v1, %v0
; CHECK-NEXT: vlgvf %r2, %v0, 3
; CHECK-NEXT: # kill: def $r2l killed $r2l killed $r2d
; CHECK-NEXT: br %r14
- %op = add i128 %a, %a
+ %op = add i128 %a, %b
%res = trunc i128 %op to i16
ret i16 %res
}
@@ -296,15 +299,16 @@ define i128 @f22(ptr %ptr) {
}
; Truncation to i8.
-define i8 @f23(i128 %a) {
+define i8 @f23(i128 %a, i128 %b) {
; CHECK-LABEL: f23:
; CHECK: # %bb.0:
-; CHECK-NEXT: vl %v0, 0(%r2), 3
-; CHECK-NEXT: vaq %v0, %v0, %v0
+; CHECK-NEXT: vl %v0, 0(%r3), 3
+; CHECK-NEXT: vl %v1, 0(%r2), 3
+; CHECK-NEXT: vaq %v0, %v1, %v0
; CHECK-NEXT: vlgvf %r2, %v0, 3
; CHECK-NEXT: # kill: def $r2l killed $r2l killed $r2d
; CHECK-NEXT: br %r14
- %op = add i128 %a, %a
+ %op = add i128 %a, %b
%res = trunc i128 %op to i8
ret i8 %res
}
@@ -383,15 +387,16 @@ define i128 @f28(ptr %ptr) {
}
; Truncation to i1.
-define i1 @f29(i128 %a) {
+define i1 @f29(i128 %a, i128 %b) {
; CHECK-LABEL: f29:
; CHECK: # %bb.0:
-; CHECK-NEXT: vl %v0, 0(%r2), 3
-; CHECK-NEXT: vaq %v0, %v0, %v0
+; CHECK-NEXT: vl %v0, 0(%r3), 3
+; CHECK-NEXT: vl %v1, 0(%r2), 3
+; CHECK-NEXT: vaq %v0, %v1, %v0
; CHECK-NEXT: vlgvf %r2, %v0, 3
; CHECK-NEXT: # kill: def $r2l killed $r2l killed $r2d
; CHECK-NEXT: br %r14
- %op = add i128 %a, %a
+ %op = add i128 %a, %b
%res = trunc i128 %op to i1
ret i1 %res
}
More information about the llvm-commits
mailing list