[X86][APX] Promote 8/16-bit LEA to 32-bit to avoid partial dependence (#161051)

Author: phoebewang

llvm/lib/Target/X86/X86InstrArithmetic.td

@@ -25,18 +25,12 @@ let SchedRW = [WriteLEA] in {
                      [(set GR32:$dst, lea32addr:$src)]>,
                      OpSize32, Requires<[Not64BitMode]>;
 
-  let Predicates = [HasNDD], isCodeGenOnly = 1 in {
-    def LEA64_8r : I<0x8D, MRMSrcMem, (outs GR8:$dst), (ins lea64_8mem:$src),
-                     "lea{b}\t{$src|$dst}, {$dst|$src}",
-                     [(set GR8:$dst, lea64_iaddr:$src)]>,
-                   OpSize16,
-                   Requires<[In64BitMode]>;
-
-    def LEA64_16r : I<0x8D, MRMSrcMem, (outs GR16:$dst), (ins lea64_16mem:$src),
-                      "lea{w}\t{$src|$dst}, {$dst|$src}",
-                      [(set GR16:$dst, lea64_iaddr:$src)]>,
-                    OpSize16,
-                    Requires<[In64BitMode]>;
+  let isCodeGenOnly = 1 in {
+    def LEA64_8r : I<0x8D, MRMSrcMem, (outs GR32:$dst), (ins lea64_8mem:$src),
+                     "lea{l}\t{$src|$dst}, {$dst|$src}", []>, OpSize32;
+
+    def LEA64_16r : I<0x8D, MRMSrcMem, (outs GR32:$dst), (ins lea64_16mem:$src),
+                      "lea{l}\t{$src|$dst}, {$dst|$src}", []>, OpSize32;
   }
 
   def LEA64_32r : I<0x8D, MRMSrcMem, (outs GR32:$dst), (ins lea64_32mem:$src),
@@ -51,6 +45,11 @@ let SchedRW = [WriteLEA] in {
                       [(set GR64:$dst, lea64addr:$src)]>;
 } // SchedRW
 
+let Predicates = [HasNDD] in {
+  def : Pat<(i8 lea64_iaddr:$src), (EXTRACT_SUBREG (LEA64_8r lea64_8mem:$src), sub_8bit)>;
+  def : Pat<(i16 lea64_iaddr:$src), (EXTRACT_SUBREG (LEA64_16r lea64_16mem:$src), sub_16bit)>;
+}
+
 // Pseudo instruction for lea that prevent optimizer from eliminating
 // the instruction.
 let SchedRW = [WriteLEA], isPseudo = true, hasSideEffects = 1 in {

llvm/test/CodeGen/X86/apx/ndd-neg-addr-index.ll

@@ -8,7 +8,7 @@ define void @neg_8bit_1(i1 %cmp) {
 ; NDD-NEXT:    andb $1, %dil, %al # encoding: [0x62,0xf4,0x7c,0x18,0x80,0xe7,0x01]
 ; NDD-NEXT:    movzbl 0, %ecx # encoding: [0x0f,0xb6,0x0c,0x25,0x00,0x00,0x00,0x00]
 ; NDD-NEXT:    negb %al, %al # encoding: [0x62,0xf4,0x7c,0x18,0xf6,0xd8]
-; NDD-NEXT:    leab 2(%rcx,%rax), %al # encoding: [0x66,0x8d,0x44,0x01,0x02]
+; NDD-NEXT:    leal 2(%rcx,%rax), %eax # encoding: [0x8d,0x44,0x01,0x02]
 ; NDD-NEXT:    movb %al, 0 # encoding: [0x88,0x04,0x25,0x00,0x00,0x00,0x00]
 ; NDD-NEXT:    retq # encoding: [0xc3]
 entry:
@@ -25,7 +25,8 @@ define void @neg_8bit_2(i8 %int8) {
 ; NDD-NEXT:    # kill: def $edi killed $edi def $rdi
 ; NDD-NEXT:    addb %dil, %dil, %al # encoding: [0x62,0xf4,0x7c,0x18,0x00,0xff]
 ; NDD-NEXT:    negb %al, %al # encoding: [0x62,0xf4,0x7c,0x18,0xf6,0xd8]
-; NDD-NEXT:    leab 1(%rdi,%rax), %al # encoding: [0x66,0x8d,0x44,0x07,0x01]
+; NDD-NEXT:    leal 1(%rdi,%rax), %eax # encoding: [0x8d,0x44,0x07,0x01]
+; NDD-NEXT:    # kill: def $al killed $al killed $eax
 ; NDD-NEXT:    mulb %dil # encoding: [0x40,0xf6,0xe7]
 ; NDD-NEXT:    testb %al, %al # encoding: [0x84,0xc0]
 ; NDD-NEXT:    retq # encoding: [0xc3]
@@ -55,7 +56,7 @@ define i32 @neg_16bit(i16 %0) {
 ; NDD-NEXT:    cmovsl %ecx, %eax # EVEX TO LEGACY Compression encoding: [0x0f,0x48,0xc1]
 ; NDD-NEXT:    andw $-256, %ax # EVEX TO LEGACY Compression encoding: [0x66,0x25,0x00,0xff]
 ; NDD-NEXT:    negw %ax, %ax # encoding: [0x62,0xf4,0x7d,0x18,0xf7,0xd8]
-; NDD-NEXT:    leaw 1(%rdi,%rax), %ax # encoding: [0x66,0x8d,0x44,0x07,0x01]
+; NDD-NEXT:    leal 1(%rdi,%rax), %eax # encoding: [0x8d,0x44,0x07,0x01]
 ; NDD-NEXT:    movzwl %ax, %eax # encoding: [0x0f,0xb7,0xc0]
 ; NDD-NEXT:    movq %rax, 0 # encoding: [0x48,0x89,0x04,0x25,0x00,0x00,0x00,0x00]
 ; NDD-NEXT:    xorl %eax, %eax # encoding: [0x31,0xc0]

llvm/test/CodeGen/X86/lea-16bit.ll

@@ -13,7 +13,8 @@ define i16 @lea16bit(i16 %in) {
 ; NDD-LABEL: lea16bit:
 ; NDD:       # %bb.0:
 ; NDD-NEXT:    # kill: def $edi killed $edi def $rdi
-; NDD-NEXT:    leaw 1(%rdi,%rdi), %ax
+; NDD-NEXT:    leal 1(%rdi,%rdi), %eax
+; NDD-NEXT:    # kill: def $ax killed $ax killed $eax
 ; NDD-NEXT:    retq
   %shl = shl i16 %in, 1
   %or = or i16 %shl, 1

llvm/test/CodeGen/X86/lea-8bit.ll

@@ -14,7 +14,8 @@ define i8 @lea8bit(i8 %in) {
 ; NDD-LABEL: lea8bit:
 ; NDD:       # %bb.0:
 ; NDD-NEXT:    # kill: def $edi killed $edi def $rdi
-; NDD-NEXT:    leab 1(%rdi,%rdi), %al
+; NDD-NEXT:    leal 1(%rdi,%rdi), %eax
+; NDD-NEXT:    # kill: def $al killed $al killed $eax
 ; NDD-NEXT:    retq
   %shl = shl i8 %in, 1
   %or = or i8 %shl, 1