From: JRobinNTA <johnrobin044@gmail.com>
Date: Tue, 9 Jun 2026 12:58:14 +0000 (-0600)
Subject: [PATCH] RISC-V: Fix static rounding mode splicing for xtheadvector [PR125395]
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=df00ab045c155e2edfb8ffa55e42109bf1402934;p=thirdparty%2Fgcc.git

[PATCH] RISC-V: Fix static rounding mode splicing for xtheadvector [PR125395]

When generating assembly for T-Head vector float conversions,
the backend used hardcoded pointer math that failed to account
for static rounding mode suffixes (e.g., .rtz). Additionally,
intercept blocks for VFCVT and VFWCVT were entirely missing,
allowing illegal static rounding modes to leak into the assembler.

This patch adds the missing conversion blocks and introduces
an offset calculation to safely bypass the mnemonic regardless
of standard RVV rounding suffixes.

	PR target/125395
gcc/ChangeLog:

	* config/riscv/thead.cc (th_asm_output_opcode): Add VFCVT
	and VFWCVT blocks. Add offset logic for static rounding suffixes.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/rvv/xtheadvector/pr125395.c: New test.
---

diff --git a/gcc/config/riscv/thead.cc b/gcc/config/riscv/thead.cc
index b16b2c443be..acf661f83e7 100644
--- a/gcc/config/riscv/thead.cc
+++ b/gcc/config/riscv/thead.cc
@@ -1144,29 +1144,81 @@ th_asm_output_opcode (FILE *asm_out_file, const char *p)
 	  return p+6;
 	}
 
-      if (get_attr_type (current_output_insn) == TYPE_VFNCVTFTOI ||
-	  get_attr_type (current_output_insn) == TYPE_VFNCVTITOF)
+      if (get_attr_type (current_output_insn) == TYPE_VFCVTFTOI
+	  || get_attr_type (current_output_insn) == TYPE_VFCVTITOF)
 	{
 	  if (strstr (p, "xu"))
 	    {
-	      get_attr_type (current_output_insn) == TYPE_VFNCVTFTOI
-			   ? fputs ("th.vfncvt.xu.f.v", asm_out_file)
-			   : fputs ("th.vfncvt.f.xu.v", asm_out_file);
-	      return p+13;
+	      get_attr_type (current_output_insn) == TYPE_VFCVTFTOI
+		? fputs ("th.vfcvt.xu.f.v", asm_out_file)
+		: fputs ("th.vfcvt.f.xu.v", asm_out_file);
+	      if (strstr (p, ".rtz") || strstr (p, ".rod"))
+		return p + 16;
+	      return p + 12;
+	    }
+	  else
+	    {
+	      get_attr_type (current_output_insn) == TYPE_VFCVTFTOI
+		? fputs ("th.vfcvt.x.f.v", asm_out_file)
+		: fputs ("th.vfcvt.f.x.v", asm_out_file);
+	      if (strstr (p, ".rtz") || strstr (p, ".rod"))
+		return p + 15;
+	      return p + 11;
+	    }
+	}
+
+      if (get_attr_type (current_output_insn) == TYPE_VFWCVTFTOI
+	  || get_attr_type (current_output_insn) == TYPE_VFWCVTITOF)
+	{
+	  if (strstr (p, "xu"))
+	    {
+	      get_attr_type (current_output_insn) == TYPE_VFWCVTFTOI
+		? fputs ("th.vfwcvt.xu.f.v", asm_out_file)
+		: fputs ("th.vfwcvt.f.xu.v", asm_out_file);
+	      if (strstr (p, ".rtz") || strstr (p, ".rod"))
+		return p + 17;
+	      return p + 13;
+	    }
+	  else
+	    {
+	      get_attr_type (current_output_insn) == TYPE_VFWCVTFTOI
+		? fputs ("th.vfwcvt.x.f.v", asm_out_file)
+		: fputs ("th.vfwcvt.f.x.v", asm_out_file);
+	      if (strstr (p, ".rtz") || strstr (p, ".rod"))
+		return p + 16;
+	      return p + 12;
+	    }
 	}
+
+      if (get_attr_type (current_output_insn) == TYPE_VFNCVTFTOI
+	  || get_attr_type (current_output_insn) == TYPE_VFNCVTITOF)
+	{
+	  if (strstr (p, "xu"))
+	    {
+	      get_attr_type (current_output_insn) == TYPE_VFNCVTFTOI
+		? fputs ("th.vfncvt.xu.f.v", asm_out_file)
+		: fputs ("th.vfncvt.f.xu.v", asm_out_file);
+	      if (strstr (p, ".rtz") || strstr (p, ".rod"))
+		return p + 17;
+	      return p + 13;
+	    }
 	  else
 	    {
 	      get_attr_type (current_output_insn) == TYPE_VFNCVTFTOI
-			   ? fputs ("th.vfncvt.x.f.v", asm_out_file)
-			   : fputs ("th.vfncvt.f.x.v", asm_out_file);
-	      return p+12;
+		? fputs ("th.vfncvt.x.f.v", asm_out_file)
+		: fputs ("th.vfncvt.f.x.v", asm_out_file);
+	      if (strstr (p, ".rtz") || strstr (p, ".rod"))
+		return p + 16;
+	      return p + 12;
 	    }
 	}
 
       if (get_attr_type (current_output_insn) == TYPE_VFNCVTFTOF)
 	{
 	  fputs ("th.vfncvt.f.f.v", asm_out_file);
-	  return p+12;
+	  if (strstr (p, ".rtz") || strstr (p, ".rod"))
+	    return p + 16;
+	  return p + 12;
 	}
 
       if (get_attr_type (current_output_insn) == TYPE_VFREDU
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/xtheadvector/pr125395.c b/gcc/testsuite/gcc.target/riscv/rvv/xtheadvector/pr125395.c
new file mode 100644
index 00000000000..5d160a22e3c
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/xtheadvector/pr125395.c
@@ -0,0 +1,26 @@
+/* { dg-do assemble } */
+/* { dg-options "-march=rv32gc_xtheadvector -mabi=ilp32d -O2 -save-temps" { target { rv32 } } } */
+/* { dg-options "-march=rv64gc_xtheadvector -mabi=lp64d -O2 -save-temps" { target { rv64 } } } */
+
+#include "riscv_vector.h"
+
+/* Test that static rounding modes do not cause string splicing in th_asm_output_opcode. */
+
+vint32m1_t test_vfncvt_ftoi(vfloat64m2_t src, size_t vl) {
+  return __riscv_vfncvt_rtz_x_f_w_i32m1(src, vl);
+}
+
+vfloat32m1_t test_vfncvt_ftof(vfloat64m2_t src, size_t vl) {
+  return __riscv_vfncvt_rod_f_f_w_f32m1(src, vl);
+}
+
+vint64m4_t test_vfwcvt_ftoi(vfloat32m2_t src, size_t vl) {
+  return __riscv_vfwcvt_rtz_x_f_v_i64m4(src, vl);
+}
+
+/* { dg-final { scan-assembler-not "\\.rtz" } } */
+/* { dg-final { scan-assembler-not "\\.rod" } } */
+/* { dg-final { scan-assembler-not "th\\.vfncvt\\..*\\.w" } } */
+/* { dg-final { scan-assembler-times "th\\.vfncvt\\.x\\.f\\.v\\s+" 1 } } */
+/* { dg-final { scan-assembler-times "th\\.vfncvt\\.f\\.f\\.v\\s+" 1 } } */
+/* { dg-final { scan-assembler-times "th\\.vfwcvt\\.x\\.f\\.v\\s+" 1 } } */